gauging - edl · pdf fileautomated gauging systems are used effectively in most mechatronics...

LEARNINGACTIVITYPACKETMECHATRONICS

B72001-AA04UEN

GAUGING

B72001-AA04UEN GAUGINGCopyright © 2012 Amatrol, Inc.

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LEARNING ACTIVITY PACKET 4

GAUGING

INTRODUCTIONAutomated gauging systems are used effectively in most mechatronics systems. They

automatically inspect parts before they are moved to the next step in the process.

This LAP reviews the operation, adjustment, and programming of one type of gauging system, a go no-go gauging system.

ITEMS NEEDEDAmatrol Supplied 87-MS2 Mechatronics Gauging Station 870-PS7313-AAU, 870-PS7314-AAU, or 870-PS7315-AAU Mechatronics Learning System for Siemens S7-300 - one per station 72024 Siemens S7-300 Programming Cable 82-900 Siemens Step 7 Programming Software

School Supplied Computer with Windows XP Operating System

Amatrol or School Supplied 41222 Hand Tool Kit or Equivalent

FIRST EDITION, LAP 4, REV. CAmatrol, AMNET, CIMSOFT, MCL, MINI-CIM, IST, ITC, VEST, and Technovate are trademarks or registered trademarks of Amatrol, Inc. All other brand and product names are trademarks or registered trademarks of their respective companies.Copyright © 2012, 2011 by AMATROL, INC.All rights Reserved. No part of this publication may be reproduced, translated, or transmitted in any form or by any means, electronic, optical, mechanical, or magnetic, including but not limited to photographing, photocopying, recording or any information storage and retrieval system, without written permission of the copyright owner.Amatrol,Inc.,2400 Centennial Blvd., Jeffersonville, IN 47130 USA, Ph 812-288-8285, FAX 812-283-1584 www.amatrol.com


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TABLE OF CONTENTS

SEGMENT 1 STATION OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4OBJECTIVE 1 Defi ne go no-go gauging and give an applicationOBJECTIVE 2 Describe how to adjust an analog sensor with a discrete output

SKILL 1 Adjust an analog sensor with a discrete outputOBJECTIVE 3 Describe the operation of a non-servo electric traverse axis

SKILL 2 Operate an automated gauging station

SEGMENT 2 ACTUATOR ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42OBJECTIVE 4 Describe how to adjust non-servo electric traverse axis travel

SKILL 3 Adjust non-servo linear traverse axis travelOBJECTIVE 5 Describe how to adjust a synchronous belt drive

SKILL 4 Adjust a synchronous belt driveOBJECTIVE 6 Describe how to adjust a clutch on a ball screw drive

SKILL 5 Adjust a clutch on a ball screw drive

SEGMENT 3 MODULE SEQUENCING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66OBJECTIVE 7 Describe a sequence of operation of a non-servo electric traverse axis

SKILL 6 Design a PLC project that sequences a non-servo electric traverse axisOBJECTIVE 8 Describe a sequence of operation of a part reject module

SKILL 7 Design a PLC project that sequences a part reject module

SEGMENT 4 STATION SEQUENCING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91OBJECTIVE 9 Describe a sequence of operation of a go no-go gauging station

SKILL 8 Design a PLC project that sequences a go no-go gauging stationOBJECTIVE 10 Describe the operation of a go no-go gauging station with manual/auto/reset functions

SKILL 9 Design a PLC project that provides manual/auto/reset functions for a go no-go gauging station


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SEGMENT 1STATION OPERATION

OBJECTIVE 1 DEFINE GO NO-GO GAUGING AND GIVE AN APPLICATION|

An automatic gauging station is a device that automatically measures one or more dimensions of a part to determine whether or not the dimensions are within a specifi c tolerance. A tolerance is the acceptable range for a physical part dimen-sion. For example, if the desired width of a part is 120 mm and the tolerance is ± 1.0 mm, the part is in tolerance if it measures between 119 mm and 121 mm, as shown in fi gure 1.

Figure 1. Part Width Tolerance

010

20

30

4050

60

70

80

90

PART

0.0ON/OFF

+/- IN/mm ZERO

120.0

DIGITALGAUGE

COMPUTER

120.0

120mm119mm121mm

DESIREDWIDTH

WIDTHTOLERANCE


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Gauging stations are often used in FMS applications to check part dimensions after parts have gone through some type of process where their dimensions change. If a part is within tolerance, it is considered good and is passed to the next station. If the part is not within tolerance, it is considered a reject and is removed from the station. Examples include machining, molding, and coating.

Figure 2. Gauging Station (Image Courtesy of Marposs Corporation)


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Many automatic gauging stations measure part dimensions by indicating the distance an indicator probe moves when placed against a part or by using sensors to measure the dimensions of a part. The digital indicator or sensor indicates the probe’s position via a digital readout or by sending data to the PLC or computer controlling the station. A “Go” is output by the system if the test passed. A “No-Go” is output if the system determines that the part’s feature is out of tolerance. The Go and No-Go outputs are used to trigger actuators to either move the part for further processing or reject it from the station.

Figure 3. Go No-Go Gauging Module


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One type of an analog sensor used in go no-go applications is the ultrasonic sensor shown in fi gure 4. In this application, a height or boundary is programmed into the sensor. When a part passes under the sensor, the sensor determines where the part is in relation to a programmed boundary. Depending on how the sensor’s output is programmed (i.e. N.O. or N.C. contacts), a signal is output to the PLC to indicate whether the tested part is a “Go” or a “No-Go.” If the part is a “Go,” it is passed to another station for further processing. If the part is a “No-Go,” it is a reject and is removed from the station.

Figure 4. Ultrasonic Sensor

UPPERBOUNDARY

LOWERBOUNDARY

PART IS GO AND IS PASSED

TO NEXT STATION

TARGET

ULTRASONICSENSOR


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Sensors used in Go No-Go gauging often use another sensor to trigger the measurement sensor. This so the measurement sensor can take the measurement at the precise moment the part is in the sensor’s path. An example is a conveyor line with a measurement inspection area along the conveyor’s path. The part to be measured travels along the conveyor on a pallet. When the pallet reaches the inspection area, it triggers a switch, such as an inductive sensor. When this trigger input is high, the measurement sensor takes a reading on the part as it travels past the sensor.

Figure 5. Sensor Used to Trigger Measurement

INDUCTIVESENSOR

CONVEYOR

PARTPALLET

PART


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OBJECTIVE 2 DESCRIBE HOW TO ADJUST AN ANALOG SENSOR WITH A DISCRETE OUTPUT

Analog sensors make it possible for PLCs to measure physical quantities such as pressure, temperature, and fl ow rate. Most analog sensors measure the physical input and then output an analog voltage or current signal that is proportional to the input. The most common signal ranges for analog sensor outputs are shown in fi gure 6.

OUTPUT TYPE

VALUE WITH ZERO INPUT

VALUE WITH MAXIMUM INPUT

Current 4 mA 20 mA

Voltage 0 VDC 10 VDC

Figure 6. Analog Sensor Output Values

Some analog sensors do not output an analog signal, but output one or more discrete outputs, which turn on or off depending on the level of the measured input signal.

One example of an analog sensor is an ultrasonic sensor, shown in fi gure 7. An ultrasonic sensor is a radiation-based level-measuring device that uses the trans-mission and refl ection of ultrasonic waves to determine the distance of an object from the sensor.


ULTRASONICSENSOR

OBJECT

ULTRASONICWAVES

ULTRASONIC WAVESREFLECTING BACK TO SENSOR


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Another application of an ultrasonic sensor with analog outputs is checking the orientation of plastic bowls, shown in fi gure 8. The sensor measures the distance between it and the bowl. When the sensor measures the inverted bowl, the distance measured is less than the distance measured when the bowl is in normal position. This information is used to determine if the bowl is oriented correctly.

Figure 8. Ultrasonic Sensor Checking Part Orientation

The repeatability of an ultrasonic sensor can be found in the manufacturer’s literature, and varies with the specifi c sensor. A typical repeatability of a sensor with a sensing range of 50-500 mm is 0.5%. This means that its actual reading could vary by as much as 2.5 mm.

ULTRASONICSENSOR

INVERTEDBOWL


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An ultrasonic sensor can also have discrete outputs. One application of an ultrasonic sensor with discrete outputs is shown in fi gure 9. This type of sensor can be programmed to operate in one of several modes, including a Window mode. In Window mode, the sensor output is used to indicate where the surface of a part is in relation to a programmed window. The upper and lower window boundaries are normally the upper and lower tolerances of the feature being measured. If the measurement is outside this boundary, the part is either too tall or too short. Based on the input from the sensor, the PLC logic determines if the part is good (Go) or a reject (No Go).

Figure 9. Ultrasonic Sensor with Discrete Outputs

The type of signal an ultrasonic sensor outputs depends on whether the sensor’s output is programmed as N.C. or N.O. contacts. The sensor’s output in Window mode is summarized in fi gures 10 and 11.

SWITCH CONFIGURATION DESCRIPTION

N.O. The sensor output is true if an object is detected within the pro-grammed window (i.e. the part is within tolerance).

N.C. The sensor output is true if an object is detected outside of the programmed window (i.e. part is outside tolerance)

Figure 10. Window Mode Output Switching

LOWER WINDOW BOUNDARY TOO SHORT (BAD PART)

WITHIN WINDOW BOUNDARIES (GOOD PART)

UPPER WINDOW BOUNDARY TOO LONG (BAD PART)

PART


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Figure 11. Window Mode Boundaries

Often, ultrasonic sensors have LEDs on the back near the cable to indicate the operation status of the sensor. Figure 12 shows the most used LED colors and their functions.

LEDDESCRIPTION

Normal Operation Programming Mode

Green Lights when the power supply volt-age is present.

Flashes when a boundary is stored into the sensor.

Red Flashes to indicate severe acoustic interference is present. The green LED should turn off.

No function.

Yellow Lights to indicate the output has been switched.

Lights when a background level is stored into the sensor.

Figure 12. LED Indicators

SENSOR

TARGETWINDOWBOUNDARY WINDOW

BOUNDARY


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Ultrasonic Sensor Adjustment

The ultrasonic sensor’s sensing window is programmed using the following four steps.

Step 1: Place the Target at the Nearest Window Boundary - The target should be placed at the window boundary closest to the sensor which is the upper window boundary, as shown in fi gure 13. If measuring a part height, this boundary represents the tallest allowable part.

A target is placed at the window boundary as shown in fi gure 13. The window boundary is the point where the sensor’s output will switch.

Figure 13. Program Nearest

SENSOR

TARGET

WINDOWBOUNDARY


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The boundary is programmed by either connecting an optional programming unit, or by manually connecting the sensor’s programming input pin to a common terminal. If the sensor is connected to a machine, the sensor’s programming input wire can be applied to common on an I/O Interface module, as shown in fi gure 14. An LED should fl ash to indicate that the boundary has been successfully stored.

Figure 14. Programming Inputs for Tallest Part

I16 I17 I18 I19 I20 I21 I22 I23

+ + + + + + + +

- - - - - - - -

ULTRASONICSENSOR

I/O INTERFACEMODULE

LEDLOCATION

PROGRAMMINGINPUT WIRE

LOADSYNCINPUT

+

-


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Step 2: Place the Target at the Farthest Window Boundary - The target should be placed at the window boundary farthest from the sensor, which is the lower boundary, as shown in fi gure 15. If measuring a part height, this boundary represents the shortest allowable part. Apply the sensor’s programming input wire to a voltage source on an I/O interface module, as shown in fi gure 16. An LED should fl ash to indicate that the boundary has been successfully stored.

Figure 15. Program Farthest Window Boundary

Figure 16. Programming Inputs for Shortest Part

LOWER WINDOW BOUNDARY

SENSOR

UNUSABLEAREA

OUTPUTACTIVE

OUTPUTINACTIVE

TARGET

NORMALLYCLOSED

OPERATION

I16 I17 I18 I19 I20 I21 I22 I23

+ + + + + + + +

- - - - - - - -

ULTRASONICSENSOR

I/O INTERFACEMODULE

LEDLOCATION

PROGRAMMINGINPUT WIRE

LOADSYNCINPUT

+

-


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SKILL 1 ADJUST AN ANALOG SENSOR WITH A DISCRETE OUTPUT

Procedure Overview

In this procedure, you will adjust the sensitivity of the ultrasonic sensor on the 87-MS2 Gauging station. This will adjust the level at which a discrete output is supplied by the sensor. This will familiarize you with adjusting analog sensor sensitivity.

1. Locate the 87-MS2 Gauging station, shown in fi gure 17.

Figure 17. Gauging Station


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2. Verify that this station has been separated from any other stations. If it has not, then separate it from the other stations. If it has, then proceed to Step 3.

3. Perform the following safety check before you begin working on the station. Make sure that you can answer yes to each item before proceeding.

YES/NO SAFETY CHECKOUT

Remove all obstructions from the work area

Check for signs of damage to the equipment

Wear tight fi tting clothing, roll up long sleeves, remove ties, scarves, jewelry, etc.

Tie up long hair

Remove any robot teach pendants from the work area

Locate the emergency stop button

Ensure that safety glasses are worn by people in area

Ensure that all people are outside any work envelopes

Figure 18. Mechatronics Safety Check

4. Perform the following substeps to open the PLC programming software.

A. Make sure that the interface from the personal computer to the PLC is connected.

B. Power up the PC and monitor.

C. Start the SIMATIC Manager. 5. Plug the station’s power cable into a wall outlet. 6. Perform the following substeps to power up the 87-MS2 Gauging Station.

A. Place the Mode Selector switch in the Manual position.

B. Remove the lockout/tagout device from the electrical power source.

C. Turn the station’s Main Power Switch to the On position. 7. Perform the following substeps to open project Gauging.

A. Click the Open Project/Library button.

The Open Project/Library dialog should open.

B. Locate project Gauging.

The project Gauging is provided on a supplemental disk.

If it is not listed on the dialog, click the Browse button on the dialog to view the projects located in the S7Proj folder.

C. Double-click the Gauging icon to open the project.

D. Select Expand All from the View menu to expand the project’s contents.

The option is “Expand All” if using STEP 7 Version 5.2 or “Show All Levels” if using STEP 7 Version 5.3.


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8. Perform the following substeps to download the PLC project named Gauging to the PLC.

A. Place the PLC’s Mode Selector switch in the RUN position.

B. Reset the PLC.

C. Download the SIMATIC 300 Station object to the PLC.

Several dialogs will appear during the download. Click the appropriate response to continue downloading the program. The last dialog should ask if you wish to perform a complete (Warm) restart.

D. Click Yes on the dialog to complete a warm restart. 9. Press the Output Power pushbutton to enable the PLC’s outputs. 10. Perform the following substeps to adjust an analog sensor.

A. Obtain from your instructor several good and bad valve bodies.

Good valve bodies have ports drilled in them and measure 0.91-0.99 inches in height. Bad valve bodies measure less than 0.895 inches and/or do not have ports drilled in them.

B. Locate the Ultrasonic sensor, shown in fi gure 19, on the Gauging station.

In this application, the ultrasonic sensor looks for valve bodies that are the correct height. If a valve body passes under the sensor, but it does not fall within the upper and lower boundary windows, the station rejects the valve body as a bad part.


ULTRASONICSENSOR


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Figure 20. Good and Bad Valve Bodies

C. Obtain from your instructor the gauge blocks, which are solid aluminum blocks with a U (upper) and an L (lower) stamped on them. The one with the U is the tallest and the one with the L is the shortest.

They will be used to program the range or window of acceptable part heights into the sensor.

D. Place the tallest gauge block, the one stamped with a U, into the recess on the traverse axis, as shown in fi gure 21.

Figure 21. Valve Body on the Traverse Axis

UPPERBOUNDARY

LOWERBOUNDARY

UPPERBOUNDARY

LOWERBOUNDARY

GOOD PART BAD PART


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E. Use the motor starter’s manual overrides, shown in fi gure 22, to position the traverse axis so that the valve body is directly under the ultrasonic sensor, as shown in fi gure 23.

Figure 22. Motor Starter Manual Overrides

Figure 23. Traverse Axis Position

SENSOR

CARRIAGE

PART

INDUCTIVESENSOR TAB

REVERSEMANUAL

OVERRIDE M2

FORWARDMANUAL

OVERRIDE M1


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F. Verify the inductive sensor is triggered by the tab on the carriage. The yellow LED should be on.

G. Locate the Digital I/O Interface module terminals shown in fi gure 24.

The + and - signal pins will be used to provide the 24VDC and common respectively to program the sensor.

Figure 24. Digital I/O Interface Module

H. Locate the gray conduit behind the I/O module as shown in fi gure 24.

I. Remove the cover from the conduit assembly by sliding it to the right.

J. Locate where the cable from the ultrasonic sensor as it enters the conduit.

This can be done by following the cable from the ultrasonic sensor.

SIGNALPINS

GRAYCONDUIT


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K. Locate the white wire with connector that ends in the conduit assembly, as shown in fi gure 25.

The white wire is the programming input for the ultrasonic sensor. It is unused during normal use.

Figure 25. Ultrasonic Sensor Programming Input

L. Remove the end cap from the connector by pulling it off.

M. Use a screwdriver to loosen one of the + and one of the - terminals (select unused terminals) on the I/O Interface Module.

WHITEWIRE

CONNECTOR

END CAP


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N. Insert the end of the connector into the - terminal for 1 second.

This programs the upper window boundary (the distance from the sensor face to the top of the part) into the sensor. The green LED on the sensor should fl ash to indicate that the boundary has been successfully stored.

O. Remove the U gauge block and replace it with the L gauge block.

P. Connect the end of the connector to the + terminal, as shown in fi gure 26, for 1 second.

This programs the lower window boundary (the distance from the sensor face to the top of the part) into the sensor. The green LED on the sensor should fl ash to indicate that the boundary has been successfully stored.

Figure 26. Programming the Ultrasonic Sensor

Q. Replace the end cap of the connector by pushing it on.

R. Replace the cover on the conduit.

S. Replace the gauge block with a known good valve body on the traverse carriage.

CONNECTORINSERTED INTO

+ TERMINAL


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11. Perform the following substeps to test the calibration of the sensor.

A. Use the motor starter’s manual overrides to position the traverse axis at the beginning of travel (BOT) position, as shown in fi gure 27.

Figure 27. Traverse Axis at Beginning of Travel Position

B. Move the traverse axis to the right by pressing motor starter M1’s manual override.

Notice the status of the ultrasonic sensor’s LEDs as the part passes under the sensor.

The LEDs should only turn on if the valve body is determined to be within the boundaries of the programmed window. In this substep, the LED should turn on because the valve body is good.

C. Reposition the traverse axis to the BOT position by pressing motor starter M2’s (reverse motor starter) manual override. Keep it pressed until the traverse axis reaches the BOT position, then release it.

D. Replace the good valve body with a bad valve body.

The bad valve body should be shorter than the good valve body. If you need to measure the valve bodies, the bad ones measure less than 0.94 inches.

E. Move the traverse axis to the right by pressing motor starter M1’s manual override.

Notice the status of the sensor’s LEDs as the part passes under the sensor.

In this substep, the LEDs should not turn on because the valve body is bad. If it does turn on, repeat Step 10 to calibrate the sensor until it oper-ates correctly with both the good and bad valve bodies.

.12. Perform the following substeps power down the station.

A. Close the SIMATIC Manager.B. Turn off the PC and monitor.C. Turn the Main Power switch Off.D. Perform a lockout/tagout on the system’s electrical power source.

BOTPOSITION

PART

ULTRASONICSENSOR


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OBJECTIVE 3 DESCRIBE THE OPERATION OF A NON-SERVO ELECTRIC TRAVERSE AXIS

A non-servo electric motor drive traverse axis moves parts back and forth between two or more set positions. The components of a non-servo controlled electric motor drive are shown in fi gure 28.

Figure 28. Components of Traverse Axis

The traverse axis carriage is used to hold and position parts for processing. The carriage is attached to the ball nut, which moves along the ball screw’s shaft as the ball screw is rotated. The ball screw is coupled to a motor through either an inline shaft, or a parallel shaft using a belt or gear reducers. The carriage is usually guided using linear bearing rods. Adjustable clamp collars may be placed on the linear bearing rods at both ends of travel to limit the motion of the carriage.

TRAVERSEDRIVE SHAFT

CLUTCHMOTOR

PULLEYS

BELT

BOT LIMITSWITCH

EOT LIMITSWITCH

ADJUSTABLECLAMP

COLLAR(HARDSTOP)

CARRIAGE

PULLEYSCARRIAGE

BALL NUT

TOP VIEW

FRONT VIEW

BALLSCREWSHAFT


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The motor is operated using a reversible motor starter. This allows it to drive in both the forward and reverse directions at a constant speed. A clutch is used to connect the motor to the belt pulleys or gears. The clutch is designed to slip at a preset torque level and protect the motor when the carriage drives into the hard stops.

Limit switches are typically placed at the beginning of travel (BOT) and end of travel (EOT) positions to indicate to the PLC that the carriage is at one of the hard stops and to turn off the motor.

Traverse Axis Operation

The traverse axis drive operates under the control of a PLC. When the traverse axis is in the BOT position, as shown in fi gure 29, a limit switch actuates to turn on an input, indicating the position to the PLC.

Figure 29. Traverse Axis

BOT SWITCH ACTIVATED

INPUT FROMBOT

LIMIT SWITCH

OUTPUT TO MOTOR STARTER

PLC CPU

DC5V

RUN

INPUTS

OUTPUTS

TOP VIEW

STARTPUSHBUTTON

INPUT


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A part is placed onto the traverse axis carriage either manually or automati-cally by another station or robot. When all of the initial conditions are satisfi ed (i.e. part present, traverse axis at BOT position, start pushbutton pressed), the PLC turns on an output to energize the motor starter and supply power to the motor. This causes the motor to turn, which drives the ball screw through either an inline shaft, belts, or gears to drive a parallel shaft. The turning ball screw causes the ball nut and traverse axis carriage to move along the ball screw shaft, as shown in fi gure 30.

Figure 30. Traverse Carriage Moving in Forward Direction

The traverse axis carriage moves until it reaches the hard stops at the EOT position. A limit switch is activated to indicate to the PLC that the traverse axis has reached the EOT position. This signal causes the PLC to turn off the output that energized the motor starter, causing the motor to stop.

The part can be removed from the traverse axis carriage and moved to another station for further processing. The PLC turns on an output to energize the reverse motor starter to turn on the motor in the reverse direction after the part has been removed. This causes the traverse axis to move back toward the BOT position. When it reaches this position, the BOT limit switch is activated, causing the PLC to turn off the output that energized the reverse motor starter, causing the motor to stop. The traverse axis is then ready to accept a part from a previous station and start the next cycle.

MOTORPULLEYS

BELT

BALL SCREWSHAFT

BALL NUT(UNDER

CARRIAGE)

CARRIAGEMOVES TO EOT

MOTORTURNING


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SKILL 2 OPERATE AN AUTOMATED GAUGING STATION

Procedure Overview

In this procedure, you will operate the 87-MS2 Gauging station. You will verify that the components of the station are properly adjusted, and run the station in both the manual and automatic modes. You will also observe how the station recovers from an emergency stop and a loss of power. This will familiarize you with the layout and operation of the Gauging station.

1. Locate the 87-MS2 Gauging station. 2. Verify that this station has been separated from any other stations. If it has

not, then separate it from the other stations. If it has, then proceed to Step 3. 3. Perform the following safety check before you begin working on the station.

Make sure that you can answer yes to each item before proceeding.





Tie up long hair







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4. Perform the following substeps to mount the parts bin. The bin is used when the station is separated from the other stations.

A. Locate the mounting bracket, red plastic parts bin, 2 T-nuts, and 2 thumb-screws, shown in fi gure 32.

Figure 32. Parts Bin and Mounting Hardware


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B. Loosen the end cap on the right side of the work surface (as you are facing the station) by prying it off.

A screwdriver may be required as the end cap may have a tight fi t. In fi gure 33, the rear end cap was loosened.

Figure 33. Loosen the End Cap

C. Slide the two T-nuts along the inside of the aluminum extrusion so that they are positioned in line with the end of the traverse.

Figure 34. Positioning the T-Nuts

T-NUTS


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D. Reattach the end cap by pushing it into the extrusion.

E. Position the mounting bracket so it is in line with the traverse. The transfer cylinder will push the parts off the carriage and into the part bin.

The milled area of the bracket faces the traverse.

F. Use a screwdriver to position the T-nuts so they are in line with the holes in the mounting bracket.

G. Insert the thumbscrews through the outside of the bracket so that the threads engage the T-nuts. Then tighten the thumbscrews by turning them CW until snug so the bracket is secure.

The T-nuts have a tendency to angle back away from vertical, so this step may take several tries.

Figure 35. Parts Bin Mounting Bracket Attached to the Station

MILLEDAREA


32

H. Mount the plastic parts bin to the bracket as shown in fi gure 36.

Figure 36. Parts Bin Mounted to the Bracket

5. Connect an air supply line to the station’s air manifold quick connect. 6. Plug the station’s power cable into a wall outlet. 7. Perform the following substeps to power up the 87-MS2 Gauging station.



C. Remove the lockout/tagout device from the pneumatic power source.

D. Turn air on to the station by shifting the lever on the lockout valve.

E. Set the station’s air supply regulator to 50 psi/345 kPa.

F. Turn the station’s Main Power Switch to the On position. 8. Perform the following substeps to open the PLC programming software.



C. Start the SIMATIC Manager. 9. Perform the following substeps to open project Gauging Station.



GOODPARTS

BIN

REJECTPARTS

BIN


33


The project Gauging was provided on a supplemental disk.



D. Select Expand All from View menu to expand the project’s contents.

The option is “Expand All” is using STEP 7 Version 5.2 or “Show All Levels” if using STEP 7 Version 5.3.

10. Perform the following substeps to download the project Gauging Station to the PLC.


B. Reset the PLC.

C. Select the SIMATIC 300 Station object by clicking it so that it is highlighted.

D. Click the Download button to download the project to the PLC.


E. Click Yes on the dialog to complete a warm restart. 11. Press the Output Power pushbutton to enable the PLC’s outputs. 12. Perform the following substeps to home the station and set manual mode.

A. Turn the Mode Selector switch to Reset.

This will home all of the actuators.

The Start pushbutton should be off when all of the actuators are in the home position.

B. Turn the Mode Selector switch back to Manual. 13. Perform the following substeps to move the station through its sequence of

operations in the manual mode for a good part. In the manual mode, each momentary press of the start pushbutton causes the

station’s next sequence step to be performed. Observe the system and notify your instructor of anything that does not

function properly or needs adjustment.

A. Obtain a good valve body from your instructor.

A good valve body has the ports milled in it and measures 0.94-1.00 inch in height.

B. Manually place a good valve body in the recess provided on the traverse carriage with the side with two holes facing PE1.

The photoelectric sensor should detect the left of the two holes on the valve body and determine the part is good.


34

C. Press and release the Start pushbutton to activate Step 1 of the sequence.

The traverse carriage should begin moving toward the EOT position. As the traverse moves, the ultrasonic sensor should make a measurement as the valve body passes underneath and send the data to the PLC. The yellow LED on the ultrasonic sensor should turn on as the part passes beneath it. The carriage should move until it reaches the hard stop at the EOT position. LS2 should activate and the motor should turn off.

You should see the following sequence occur.

1. Extend Traverse

2. Stop motor/Extend Lift cylinder

3. Extend Transfer cylinder

4. Retract Transfer cylinder

5. Retract Lift cylinder

6. Retract Traverse

7. Cycle ends

D. Press and release the Start pushbutton to activate step 2 of the sequence.

The Lift Cylinder should extend fully and stop, raising the valve body.

E. Press and release the Start pushbutton to activate step 3 of the sequence.

Because the PLC compared the data from the ultrasonic sensor and deter-mined the part was good, the Transfer cylinder should extend and push the valve body off of the carriage.

F. Press and release the Start pushbutton to activate step 4 of the sequence.

The transfer cylinder should retract fully.

G. Press and release the Start pushbutton to activate step 5 of the sequence.

The Lift cylinder should retract fully.

H. Press and release the Start pushbutton to activate step 6 of the sequence.

The carriage should move toward the BOT position. When the carriage reaches limit switch LS1, it should activate and the motor should turn off. This is step 7 of the sequence.

14. Perform the following substeps to move the station through its sequence of operations in manual mode for a bad valve body.

A. Obtain a short valve body from your instructor.

A short valve body measures less than 0.94 inches.

B. Manually place the bad valve body in the recess provided on the traverse carriage with the side with two holes facing PE1.

The photoelectric sensor should detect the left of the two holes on the valve body and determine the part is good.

C. Press and release the Start pushbutton to activate Step 1 of the sequence for a bad or rejected part.


35

The traverse carriage should begin moving toward the EOT position. As the traverse moves, the ultrasonic sensor should make a measurement as the valve body passes underneath and send the data to the PLC. The yellow LED on the ultrasonic sensor should not turn on as the part passes beneath it. The carriage should move until it reaches the hard stops at the EOT position. LS2 should activate and the motor should turn off.

You should see the following sequence occur.

1. Extend Traverse

2. Stop motor/Extend Lift cylinder

3. Extend Reject cylinder

4. Retract Reject cylinder

5. Retract Lift cylinder

6. Retract Traverse

7. Cycle ends

D. Press and release the Start pushbutton to activate step 2 of the sequence.

The Lift Cylinder should extend fully and stop, raising the valve body.

E. Press and release the Start pushbutton to activate step 3 of the sequence.

Because the PLC compared the data from the ultrasonic sensor and deter-mined the part was not good, the reject cylinder should extend and push the valve body off of the carriage.

F. Press and release the Start pushbutton to activate step 4 of the sequence.

The reject cylinder should retract fully.

G. Press and release the Start pushbutton to activate step 5 of the sequence.

The Lift cylinder should retract fully.

H. Press and release the Start pushbutton to activate step 6 of the sequence.

The carriage should move toward the BOT position. When the carriage reaches limit switch LS1, it should activate and the motor should turn off. This is step 7 of the sequence.

15. Turn the Mode Selector switch to Auto. If you successfully single-stepped through the complete sequence and all

of the actuators are back in their home position, the Start pushbutton lamp should be off at this time and you can move on to Step 17. If it is not, perform Step 16 to reset the actuators.

16. Perform the following substeps to home the station and set automatic mode.


This will move all of the actuators back to their home positions.

B. Turn the Mode Selector switch to Auto.

Once the actuators are reset and automatic is selected, the Start push-button lamp should be off.

17. Place a valve body in the recess provided on the carriage. Make sure the valve body is oriented as in Step 13B.


36

18. Press the Start pushbutton to start the automatic cycle. Observe the station while it goes through one cycle. It is programmed to run

through one cycle and then stop. The Start pushbutton indicator is on solid during the whole cycle to indicate the station is operating.

19. Perform the following substeps to record the operation of the station when the Stop pushbutton is pressed.

This will show you how the system is programmed to respond to the Stop pushbutton.

A. Load the carriage with a valve body in the correct orientation.

B. Press the Start pushbutton to start an automatic cycle.

C. During the middle of the cycle press the Stop pushbutton to stop the system.

The Stop pushbutton is programmed as a halt function, which means the station will complete its current sequence step and stop with all power remaining on.

You should see the operation continue to the end of the current sequence step and stop.

D. Observe the operator panel indicators and record their status in the table below.

OPERATOR PANEL INDICATORS

Indicator Status (On/Off/Blinking)

Output Power Lamp

Start Lamp

Emergency Stop Lamp

Figure 37. Operator Panel Indicators

Since this is a halt, the machine can resume operation, so you should observe that Output power remains on and the Start pushbutton should be off. It has been programmed to do so when the auto program has been halted. The Emergency Stop lamp should be off because it is not pressed.

E. Observe the PLC processor’s status indicators and record their status.

PLC PROCESSOR STATUS INDICATORS

Indicator Status (On/Off)

SF

DC5V

FRCE

RUN

STOP

Figure 38. PLC Processor Status Indicators


37

You should see that the PLC processor’s DC5V and Run indicator lights are on, because the station is halted and ready to resume automatic operation.

F. Observe the PLC I/O modules’ status indicators to see if any of them are on.

You should see various input and output indicators on. Which ones are on depend on the point in the operation at which the Stop pushbutton was pushed.

G. Press the Start pushbutton to restart the system.

It should continue where it left off and fi nish the cycle.

NOTE

If any actuators are manually moved while the system is halted, the station may not resume operation when the start pushbutton is pressed. If this occurs, go to Step 20 and restart the system.

H. Repeat substeps A-G three times, stopping the cycle with the Stop push-button at different times to observe how it reacts.

I. Proceed to Step 21. 20. Perform the following substeps to restart the station if any of the inputs

change after the Stop pushbutton is pressed. If any of the inputs were changed, like a part removed from the traverse

axis, or a cylinder moved physically, the system cannot be restarted with the Start pushbutton. This is because the input signals will no longer match those needed to begin the sequence. This is a protective measure to prevent damage to the system.

A. Remove any valve bodies from the carriage.

B. Turn the Mode Selector switch to Reset.


Once the actuators are reset, the Start pushbutton should turn off.

C. Load the carriage with a valve body in the correct orientation.

D. Turn the Mode Selector switch back to Auto.

E. Press and release the Start pushbutton to start the automatic cycle.

Observe the system while it goes through a cycle before continuing to the next step.

21. Perform the following substeps to record the operation of the station when the Emergency Stop pushbutton is pressed.

This step will show you how the system is programmed to respond to the emergency stop pushbutton.

A. Load the carriage with a valve body in the correct orientation.

B. Press and release the Start pushbutton.

C. During the cycle, press the Emergency Stop pushbutton.


38

D. Observe the operator panel indicators and record their status in the table below.



Output Power Lamp

Start Lamp

Emergency Stop Lamp


Since this is an Emergency Stop, the machine cannot resume operations. You should observe that the Output Power is off, the Start pushbutton lamp is off, and the Emergency Stop lamp is on. The Emergency Stop function does not remove the air supply.

E. Observe the PLC processor’s status indicators and record their status.



SF

DC5V

FRCE

RUN

STOP


You should see the PLC processor’s DC5V and Run indicator lights on.

F. Observe the PLC I/O modules’ status indicators to see if any of them are on.

You should see various input indicators on, but all output indicators are off. This is because the Emergency Stop circuit breaks power to the Output Power contactor, which drops all output power.

22. Perform the following substeps to recover from the Emergency Stop.

A. Remove any valve bodies on the carriage.

B. Pull the Emergency Stop pushbutton out.

C. Press the Output Power pushbutton to turn the outputs back on.

You should hear the contactor pull in to re-establish the power to the outputs.

D. Turn the Mode Selector switch to Reset.

This will move all of the actuators back to their home positions. Once the actuators are reset, the Start pushbutton lamp should be off.

E. Place a correctly oriented valve body into the recess on the carriage.

F. Turn the Mode Selector switch back to Auto.


39

G. Press and release the Start pushbutton to start the automatic cycle.

Observe the system while it goes through a cycle.

H. Press the Stop pushbutton after the cycle completes.

I. Load the carriage with a correctly orientated valve body after the cycle completes.

23. Perform the following substeps to record the operation of the station when it experiences a power loss.

This will show you how the station is programmed to respond to a power loss.

A. Press the Start pushbutton to start an automatic cycle.

B. During the middle of the cycle turn the Main Power switch to Off to remove power to the system.

C. Observe the operator panel indicators and record their status in the table below.



Output Power Lamp

Start Lamp

Emergency Stop Lamp


Because this is a power loss, simulated by turning the Main Power switch off, power to everything past the Main Power switch is turned off. You should see all operator panel indicator lamps and PLC indicators are off, but you will notice that the pneumatic power remains. You should also have seen any cylinders complete their strokes because they are pneumatically-operated.

D. Observe the PLC processor’s status indicators and record which indica-tors are on.



SF

DC5V

FRCE

RUN

STOP


You should see all indicators off because there is no power to the PLC.

E. Observe the PLC I/O modules’ status indicators to see if any of them are on.

Again, you should see all input and output indicators off because the modules have no power.


40

24. Perform the following substeps to recover from the power loss.

A. Remove any valve bodies that are on the carriage.

B. Place the Mode Selector switch in the Manual position.

C. Turn the station’s Main Power switch to the On position.

D. Press the Output Power pushbutton to enable the PLC’s outputs.

You should also hear the contactor located next to the PLC module pull in. The Start pushbutton should be blinking because the station is not ready for operation.

E. Turn the Mode Selector switch to Reset.


F. Turn the mode selector switch to Auto.

Once the actuators are reset, the Start pushbutton should turn off.

G. Place a correctly oriented valve body onto the carriage.

H. Press the Start pushbutton to restart the operation.

You should see the system start through its sequences.

I. Run the system through two complete cycles to make sure it has recovered correctly.

25. Perform the following substeps to power down the station.

A. Turn the Main Power switch Off.

B. Close the SIMATIC Manager.

C. Turn off the PC and monitor.

D. Perform a lockout/tagout on the system’s electrical power source.

E. Perform a lockout/tagout on the system’s pneumatic power source.


41

SEGMENT 1 SELF REVIEW

1. A tolerance is an acceptable _____ for a physical part dimension.

2. If a part’s feature is out of tolerance a _____ is output to the PLC or computer.

3. Analog sensors measure the physical input and then output an analog voltage that is _____ to the input.

4. One operating mode of an ultrasonic sensor is _____ mode.

5. A clutch in a traverse axis is designed to _____ at a preset torque level and protect the motor when the carriage drives into the hard stop.

6. A non-servo traverse axis moves parts back and forth between two or more ______.


42

SEGMENT 2ACTUATOR ADJUSTMENT

OBJECTIVE 4 DESCRIBE HOW TO ADJUST NON-SERVO ELECTRIC TRAVERSE AXIS TRAVEL

A non-servo traverse axis typically uses adjustable hard stops for positioning, as shown in fi gure 43. The carriage is positioned in one position or another by the ball screw driving the carriage against a hard stop. A limit switch is typically posi-tioned so that it actuates as the axis reaches the hard stop, sending a signal to the PLC to stop the motor and sequence another step.

Figure 43. Hard Stops and Limit Switches

If the limit switch is not adjusted properly, it will either send a signal to the PLC before the hard stop is reached, which will cause the traverse axis to be out of position, or it will not actuate, causing the motor to continue to turn after the traverse axis has reached the hard stop.

LIMITSWITCHES HARD

STOP

BALL SCREWSHAFT

CARRIAGE


43

To change the amount of travel of a traverse axis, the hard stops and limit switches must be adjusted. One method of providing adjustable hard stops is to use clamp collars on the linear bearing guide rods that guide the carriage as it moves, as shown in fi gure 44. If more than one collar is used, they must be positioned so that they contact the traverse axis carriage at the same time to prevent the carriage from being misaligned. The stops must be positioned to place the traverse axis in the correct position to process the part and actuate the limit switch at the correct time.

Figure 44. Clamp Collar

CLAMPCOLLAR

LINEARGUIDE ROD


44

Adjusting Traverse Axis Travel

Use the following steps to adjust the traverse axis travel using a clamp collar and limit switches.

Step 1: Loosen the Set Screw - The set screw is accessed by manually posi-tioning the traverse axis so that the clamp collar is exposed, as shown in fi gure 45. The screw is loosened using the appropriate size hex or allen key.

Figure 45. Accessing the Collar

Step 2: Position the Collar and Tighten the Set Screw - The collar must be positioned correctly so that the traverse axis reaches the correct position to process the part. The collar can be positioned by manually moving the traverse axis to the correct position, and sliding the collar up against the carriage and tightening the set screw. If the set screw cannot be accessed with the traverse axis in position, the collar rod can be marked using a grease pencil when the traverse axis is in the correct position. The traverse axis can then be moved out of the way manually, the collar moved so that it is next to the mark, and the set screw tightened.

Step 3: Check the Positioning - The traverse axis should be manually moved against the hard stop (collar) and its position verifi ed. If the position is not correct, steps 1 and 2 should be repeated. If more than one collar is used, make sure that they contact the carriage at the same time. This prevents the carriage from cocking to one side if it only strikes one of the collars.

SETSCREW


45

Step 4: Adjust the Limit Switch - The limit switch’s position is adjusted by loosening the set screws, shown in fi gure 46, and sliding the limit switch along the rail. The traverse axis should be placed against the hard stop. The limit switch signal can be monitored by either using a multimeter on the switch’s terminals or the I/O interface module terminals, or by using the PLC indicators. If the PLC is used, power should be applied to the PLC but it should be in STOP mode to prevent any machine movement. The limit switch should be positioned so that it has just actuated with the traverse axis in position. This can be verifi ed by moving it back and forth slightly along the rail and monitoring the input signal. When the limit switch is in the proper position, the set screws are tightened.

Figure 46. Limit Switch Set Screws

SET SCREWS

LIMITSWITCH


46

SKILL 3 ADJUST NON-SERVO LINEAR TRAVERSE AXIS TRAVEL

Procedure Overview

In this procedure, you will adjust the traverse distance of the linear traverse axis by changing the position of the stop. This will familiarize you with adjusting the stops on the linear traverse axis and with its operation.








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4. Verify the red plastic parts bin is attached onto the mounting bracket at the EOT position.

The bin is used when the station is separated from the other stations. 5. Connect an air supply line to the station’s air manifold quick connect. 6. Plug the station’s power cable into a wall outlet. 7. Perform the following substeps to power up the 87-MS2 Gauging station.




D. Turn on the air to the station by shifting the lever on the lockout valve.


F. Turn the station’s Main Power Switch to the On position.


47




C. Start the SIMATIC Manager. 9. Perform the following substeps to open project Gauging Station.




The project Gauging Station was provided on a supplemental disk.



D. Select Expand All from the View menu to expand the project’s contents.

The option is “Expand All” is using STEP 7 Version 5.2 or “Show All Levels” if using STEP 7 Version 5.3.

10. Perform the following substeps to download the project Gauging to the PLC.


B. Reset the PLC.

C. Select the SIMATIC 300 Station object by clicking it so that it is highlighted.

D. Click the Download button to download the project to the PLC.


E. Click Yes on the dialog to complete a warm restart. 11. Press the Output Power pushbutton to enable the PLC’s outputs. 12. Perform the following substeps to home the station and set manual mode.


This will home all of the actuators.

B. Turn the Mode Selector switch back to Manual.


48

13. Perform the following substeps to adjust the EOT hard stop on the traverse axis.

The stop will be adjusted so that the carriage stops earlier in its travel.

Figure 48. Adjustable Clamp Collars

A. Use the motor starter manual overrides to position the carriage in its EOT position. This is the end opposite the motor

B. Mark the position of the carriage on the guide rod using tape or a grease pencil. You will need to move it back to its original position later in the skill.

C. Loosen the set screws on the clamp collar using a 7/64 in. hex wrench.

D. Slide the clamp collar to the right so it is out of the way.

MOVE CLAMP

COLLAR RIGHT

LS2


49

E. Using the motor starter manual overrides, position the carriage in the new EOT position, as shown in fi gure 49.

The carriage should almost touch the bracket for the transfer bin.

Figure 49. Carriage in New EOT Position

F. Slide the clamp collar up against the carriage.

G. Tighten the set screw.

H. Locate the limit switch LS2.

This limit switch, shown in fi gure 51, is on the back side of the traverse axis frame near the hard stop you just adjusted.

I. Mark the current location of the limit switch with a pencil or tape.

J. Loosen the set screws that attach the limit switch to the rail.

K. Move the switch toward the carriage.

L. Move the switch body forward until the limit switch actuator arm is just touching the carriage.

M. Monitor PLC input status indicator I1.6 and move the limit switch forward until you now see that the PLC indicator turns on.

N. Tighten the set screws that attach the limit switch to the rail. 14. Perform the following substeps to test the adjustment.

A. Turn the Mode Selector switch to the Reset position.

B. Turn the Mode Selector switch to Auto.

C. Load the traverse carriage with a valve body.

D. Press and release the Start pushbutton.

Observe the operation of the station. The carriage should move to the right until it strikes the hard stop. If the limit switch is properly adjusted, it should actuate and the motor should stop. If it does not stop, repeat Step 13 substeps J through N to adjust the limit switch. Otherwise the station should perform the rest of its sequence.

BRACKETFORBIN


50

15. Perform the following substeps to adjust the hard stop to its original position.

A. Loosen the set screw on the clamp collar.

B. Move the clamp collar back to the right so it is out of the way.

C. Use the motor starter manual overrides to move the carriage back to its original EOT position, which you marked previously.

D. Move the clamp collar to the left so that it is against the carriage.

E. Tighten the set screw.

F. Adjust limit switch LS2.

PLC input status indicator I1.6 should turn on just as the carriage reaches the hard stop.

16. Perform the following substeps to test the adjustment.

A. Turn the Mode Selector switch to the Auto position.

B. Place a valve body onto the traverse axis.

C. Press and release the Start pushbutton.

Observe the operation of the station. It should perform its sequence. The carriage should move to the right, the Lift cylinder should extend to lift the part, and either the Reject or Transfer cylinder should extend to place the part in either the Reject bin or Transfer bin.

Make sure that the carriage is in the correct position when the part is being removed from the traverse axis.

D. Press the Stop pushbutton after the carriage stops.

If the adjustment is correct, continue to Step 17, otherwise repeat Steps 15 and 16 until the hard stop is properly adjusted.


A. Close the SIMATIC Manager.

B. Turn off the PC and monitor.

C. Turn the Main Power switch Off.

D. Perform a lockout/tagout on the system’s electrical power source.

E. Perform a lockout/tagout on the system’s pneumatic power source.


51

OBJECTIVE 5 DESCRIBE HOW TO ADJUST A SYNCHRONOUS BELT DRIVE

Synchronous drive belts are often used to transmit power for applications that require precision positioning because their gear-like teeth engage the pulley grooves, preventing belt slippage. A synchronous drive belt is shown in fi gure 50.

Figure 50. Synchronous Drive Belt

TEETH ON BELTENGAGE PULLEY

GROOVES

BELT


52

When installing a synchronous belt, pay close attention to the alignment and tensioning of the belt. The alignment is very important to keep the belt running in the center of the drive. If the alignment is off, the belt will always run up against the pulley fl anges causing excessive belt edge wear.

The tension of the belt is also important. In most cases, it is satisfactory to tension a synchronous belt to a snug fi t, but on a heavily loaded drive, adjust to the appropriate tension according to the manufacturer’s specifi cations. Synchronous belt tension can be measured using the same type of belt tension tester used for other types of belts.

Figure 51. Measuring Belt Tension

INC

HE

S o

f SPA

NP

OU

ND

S50

510

1520

2530

3540

100

150

DRIVEN

DRIVER

TENSIONTESTER


53

Synchronous Drive Belt Installation and Adjustment

The procedure to install a synchronous belt drive is as follows:

Step 1: Inspect the Pulleys - Inspect both of the pulleys for cleanliness and wear. The pulleys should be cleaned if they are dirty. If there is excessive wear on any of the pulley’s surfaces, they should be replaced.

Step 2: Mount the Pulleys onto the Shafts - Pulleys are generally mounted using a hex or allen head set screw, as shown in fi gure 52. Each pulley should be placed onto the shaft and the set screws tightened.

Figure 52. Pulley with Set Screw

SET SCREW

PULLEY


54

Step 3: Install the Belt - The motor’s locking nuts should be loosened and the motor moved closer to the driven shaft. It should be moved close enough to be able to place the belt over both of the pulleys. After the belt has been positioned, the motor should be moved away until the belt becomes snug. The locking nuts should then be tightened.

Figure 53. Install the Belt

BELT


55

Step 4: Align the Pulleys - The pulleys are aligned by placing a straight edge against the face of both pulleys. If both pulleys are aligned, all four edges of the pulleys (PT1-PT4) should be touching the straight edge, as shown in fi gure 54.

Figure 54. Proper Pulley Alignment

If they are not aligned, the set screws should be loosened on the misaligned pulley and the pulley adjusted so that both of its edges touch the straight-edge. The set screws should be tightened and the alignment should be rechecked. The proce-dure should be repeated until both of the pulleys are properly aligned.

Step 5: Apply Tension to the Belt - With synchronous belts, a snug fi t usually provides satisfactory tension. Drives with unusually high loads should be tensioned according to the manufacturer’s specifi cations.

Step 6: Re-inspect the Belt - The belt tension should be re-inspected after approximately 24 to 48 hours of operation.

01

23

45

67

89

1011

12

PT1

PT2

PT3

PT4


56

SKILL 4 ADJUST A SYNCHRONOUS BELT DRIVE

Procedure Overview

In this procedure, you will adjust both the tension and alignment of the synchronous belt drive. This will familiarize you with performing the adjustments required by a synchronous belt drive.








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4. Perform the following substeps to prepare the belt drive to be adjusted.

A. Using a grease pencil, mark the motor mount location on the extruded aluminum work surface so it can be returned to the same location after it has been moved.


57

B. Loosen the motor mounting screws, shown in fi gure 56, using a 9/64 in. hex wrench.

Figure 56. Motor Mounting Screws

C. Slide the motor towards the traverse axis so that the belt loosens.

D. Remove the belt from the pulleys

E. Inspect both of the pulleys for cleanliness and wear. Clean the pulleys if they are dirty.

5. Perform the following substeps to mount the belt.

A. Move the motor toward the traverse axis.

B. Place the belt over both of the pulleys. 6. Perform the following substeps to align the pulleys.

A. Reposition the motor so that it is back in its original position, which you marked earlier with a grease pencil.

B. Tighten the motor mounting screws.

MOTORMOUNTINGSCREWS


58

C. Place a straight edge against the face of both pulleys.

If both pulleys are aligned, all four edges of the pulleys (PT1-PT4) should be touching the straight edge, as shown in fi gure 57.

Figure 57. Properly Aligned Pulleys

7. If the pulleys are aligned, continue to Step 8. Otherwise, perform the following substeps to align the pulleys.

A. Loosen the motor mounting screws.

B. Adjust the motor so that all four edges of the pulleys touch the straight edge as shown in fi gure 57.

C. After the pulleys are aligned, tighten the motor mounting screws.

D. Check the alignment after the mounting screws have been tightened.

If the alignment is correct, continue to Step 8. If it is not correct, repeat substeps A through D.

8. Perform the following substeps to check belt tension.

A. Press on the top of the belt with your fi nger.

It should defl ect no more than ¼ inch.

B. If the tension is OK proceed to Step 9, otherwise perform the following substeps.

C. Loosen the motor mounting screws.

01

23

45

67

89

1011

12

PT1

PT2

PT3

PT4


59

D. Move the motor away from the traverse axis so that the belt tightens.

Make sure that you do not move it so that the pulleys are misaligned.

E. Tighten the motor mounting screws.

F. Check the pulley alignment.

If it is OK, proceed to substep G, otherwise perform the pulley alignment procedure.

G. Press on the top of the belt with your fi nger.

The belt should defl ect no more than ¼ inch.

If the tension is OK, proceed to Step 9, otherwise, repeat substeps C through G.

9. Plug the station’s power cable into a wall outlet. 10. Perform the following substeps to power up the 87-MS2 Gauging station.



C. Turn the station’s Main Power Switch to the On position. 11. Press the Output Power pushbutton to enable the PLC’s outputs. 12. Perform the following substeps to test the belt drive.

A. Locate motor starters M1 and M2.

B. Press motor starter M1’s manual override to drive the traverse table away from the BOT position.

C. Watch the belt as the motor is rotating.

Make sure that the belt operation is smooth and that the belt is not rubbing against one side of either pulley.

D. Press motor starter M2’s manual override to drive the traverse table back to the BOT position.

E. If the alignment seems correct, proceed to Step 13, otherwise turn off power and repeat Steps 7 through 12 to readjust and test the belt.



B. Perform a lockout/tagout on the system’s electrical power source.


60

OBJECTIVE 6 DESCRIBE HOW TO ADJUST A CLUTCH ON A BALL SCREW DRIVE

A clutch is mechanical device that uses either mechanical, magnetic, hydraulic, pneumatic or friction connections to engage and disengage two rotating members. Its main function is to disconnect the drive motor from the driven member. A common example is the clutch located between a conveyor drive motor and the conveyor drive pulley. The motor rotates and applies its rotational energy to the clutch, which supplies rotational energy to the drive pulley. In industrial applica-tions, the clutch is usually placed between a motor and a driven member and is designed to slip at a preset torque level to protect the motor from burning out if excessive loads are encountered.

Figure 58. Clutch Application

MOTORPULLEYS

CLUTCH


61

A non-servo traverse axis drive may also use a multi-plate slip clutch between the motor and the driven member (i.e. belt pulley or gears), as shown in fi gure 59. The traverse axis is driven into the hard stops at either end to position the axis. The clutch “slips” when the hard stop is reached, preventing the motor from burning out if the limit switch used to send a signal to the PLC is misadjusted, and does not send a signal to the PLC to stop the motor.

The adjustment knob on a multi-plate slip clutch applies force to the springs (which are guided). The other ends of the springs apply force along the clutch rota-tion axis to the disc stack. The disc stack is made of smaller discs, friction pads and larger discs. The smaller discs have fl ats on their inner diameter so that they cannot turn relative to the hub that they surround (the hub has mating fl ats). However, the larger discs have circular inner diameters and can rotate relative to the hub. The friction pads separate the larger from the smaller discs. The larger discs have holes near their outside diameters. Pins inserted through these holes transmit torque out of the clutch to the larger hub that has the pins mounted to it.

Figure 59. Multi-Plate Slip Clutch

The friction pads are the components that supply the slip in the clutch. When the torque exceeds the amount of friction between the pads and the discs, the pads slip against the surface of either the large or small disc.

The torque level at which the clutch slips is controlled by compressing the springs, shown in fi gure 59, with the adjusting knob. Turning the knob counter-clockwise causes less force to be applied to the springs, reducing the amount of torque required for the clutch to slip. Turning the knob clockwise causes more force to be applied to the spring, increasing the amount of torque required for the clutch to slip.

TORQUE PINS

DISC STACK

HUBLARGE DISC

SMALL DISC

SPRINGS

ADJUSTMENTKNOB

FRICTIONPAD

REDUCED TORQUETRANSMITTED TO

THIS SIDE

FRICTION PADIS LOCATION OF

SLIPPAGE

TORQUEAPPLIED

HERE


62

SKILL 5 ADJUST A CLUTCH ON BALL SCREW DRIVE

Procedure Overview

In this procedure, you will adjust the clutch on the ball screw drive to different levels and test the operation of the clutch. This will familiarize you with the operation and adjustment of the clutch on the ball screw drive.








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4. Plug the station’s power cable into a wall outlet. 5. Perform the following substeps to power up the 87-MS2 Gauging Station.



C. Turn the station’s Main Power Switch to the On position.


63

6. Perform the following substeps to reduce the torque setting on the multi-plate slip clutch.

A. Locate the clutch assembly and motor starters shown in fi gure 61.

Figure 61. Clutch Assembly and Motor Starters

B. Turn the knurled adjustment knob, shown in fi gure 62, CCW (looking at the rear of the clutch assembly) two or three turns.

You should be able to see that the tension on the springs is being reduced as you turn the knob.

Figure 62. Clutch Torque Adjustment Knob

C. Press motor starter M1’s manual override.

The torque setting should be very low. The motor may rotate, but the clutch might slip, and the traverse axis will stay in position.

D. Release motor starter M1’s manual override.

E. If the clutch did not slip, reposition the axis to the left-hand side stops and turn the adjustment knob one more turn counter-clockwise. Repeat substeps C and D.

If the clutch did slip and the axis did not move, proceed to Step 7, other-wise repeat substeps A through C.

7. Perform the following substeps to increase the torque setting on the multi-plate slip clutch.

A. Turn the knurled adjustment knob CW (looking at the rear of the clutch assembly) two or three turns.

You should be able to see that the tension on the springs is being increased as you turn the knob.

CLUTCHMOTOR

STARTERS

CLUTCH TORQUE

ADJUSTMENT KNOB


64

B. Press motor starter M1’s manual override.

The torque setting should be high enough that the traverse axis should move.

C. Observe the movement of the traverse axis.

If the torque setting is high enough, the clutch will not slip and the axis should move smoothly until it hits the hard stops. If the clutch slips while the axis is moving the torque setting is not high enough. The clutch should slip after the axis hits the hard stop. If not the torque setting is too high.

D. Based on your observations, if the clutch is properly adjusted, proceed to step 8.

If the clutch is not properly adjusted, reposition the axis to the left-hand side hard stops.

E. Turn the adjustment knob the required direction (CCW if the torque setting is too high, and CW if it is too low).

F. Press motor starter M1’s manual override and observe the operation of the axis, motor, and clutch.

G. Repeat substeps C through F until the torque setting is correct. 8. Perform the following substeps power down the station.


B. Perform a lockout/tagout on the system’s electrical power source.


65


1. A non-servo traverse axis generally uses _____ for positioning.

2. When the traverse axis reaches its end of travel, it triggers a _____, which sends a signal to the PLC to stop the motor and sequence another step.

3. The type of drive belt used to transmit power in precision applications is called a _____ drive belt.

4. If belt alignment is off, the belt will always run up against the _____ causing excessive belt edge wear.

5. The torque level at which a clutch slips is controlled by compressing the springs with the _____.

6. Clutches use either mechanical, magnetic, hydraulic, pneumatic, or _____ connections to engage and disengage two rotating members.


66

SEGMENT 3MODULE SEQUENCING

OBJECTIVE 7 DESCRIBE A SEQUENCE OF OPERATION OF A NON-SERVO ELECTRIC TRAVERSE AXIS

A non-servo traverse axis, shown in fi gure 63, includes a motor-driven carriage and two end-of-travel sensors, such as limit switches. A fi xture is typically attached to the carriage to hold the parts being transported. The traverse axis moves between the beginning of travel (BOT) and end of travel (EOT) positions when driven by the motor. The end-of-travel sensor’s inputs indicate to the controller that the traverse axis has reached one of its end-of-travel positions.

Figure 63. Traverse Axis Construction

A typical sequence of operation of a non-servo traverse axis is:

NON-SERVO ELECTRIC TRAVERSE AXIS SEQUENCE

STEP INPUT OUTPUT

1 Receive Start Input (S1 on) Forward motor starter engaged (M1 on)

2 Traverse extended (LS2 on) Motor turns off

3 Receive input (S2 on) Reverse motor starter engaged (M2 on)

4 Traverse retracted (LS1 on) Motor turns off/Cycle Ends

Figure 64. Non-Servo Traverse Axis Sequence of Operation

BOT SWITCH

(LS1)

EOT SWITCH

(LS2)CARRIAGE

M1

MOTOR

M2

MILLED RECESSTO HOLD PART


67

Initial Condition

The traverse axis must be in a home position before a sequence can start. The traverse axis is in the home position when it is fully retracted to its BOT position, as shown in fi gure 65. In this position, limit switch LS1 is activated, sending a signal to the controller that the axis is in the home position.

Figure 65. Initial Condition

REVERSECONTACTOR

M1

M1

M2

M2

FORWARDCONTACTOR

CARRIAGE

LIMITSWITCH

REV FWD

LS1 LS2

LIMITSWITCH

CLUTCH

24 VDC

GND

LS1 ONCARRIAGE

AT BOT POSITION

M1OFF

M2OFF


68

Step 1: Receive Start Input, Forward Motor Starter Engaged

In this step, the PLC controlling the traverse axis receives an input to start the traverse axis sequence. The input may be from another workstation, an operator, or the robot tending the traverse axis. After receiving the input signal, the PLC energizes forward motor starter, M1, causing the motor to rotate.

The motor rotation causes the carriage to move away from the BOT position. As the carriage leaves the BOT position, limit switch LS1 is deactivated.

Figure 66. Step 1: Receive Start Input, Forward Motor Starter Engaged

REVERSECONTACTOR

M1

M1

M2

M2

FORWARDCONTACTOR

CARRIAGE

LIMITSWITCH

REV FWD

LS1 LS2

LIMITSWITCH

CLUTCH

24 VDC

GND

CARRIAGE BEGINS TO EXTENDTOWARD EOT POSITION

M1ON


69

Step 2: Traverse Extended/LS2 Activated, Motor Turns Off

The carriage moves until it strikes the hard stops at the EOT position. At the EOT position, LS2 is actuated, sending a signal to the PLC to stop the motor by turning off M1. At the EOT position, the part may be removed from the traverse axis.

Figure 67. Step 2: Traverse Extended/LS2 Activated, Motor Turns Off

REVERSECONTACTOR

M1

M1

M2

M2

FORWARDCONTACTOR

CARRIAGE

LIMITSWITCH

REV FWD

LS1 LS2

LIMITSWITCH

CLUTCH

24 VDC

GND

CARRIAGE AT EOT POSITION

M1OFF

LS1OFF

LS2ON


70

Step 3: Receive Input, Reverse Motor Starter Engaged

After the part is removed, the PLC receives an input signal to return the traverse axis to the BOT position. The input may be from another workstation, an operator, or the robot tending the traverse axis. After receiving the input signal, the PLC energizes motor starter M2, causing the motor to rotate in the reverse direction. As the motor rotates, the carriage moves away from the EOT position, de-activating limit switch LS2.

Figure 68. Step 3: Receive Input, Reverse Motor Starter Engaged

REVERSECONTACTOR

M1

M1

M2

M2

FORWARDCONTACTOR

CARRIAGE

LIMITSWITCH

REV FWD

LS1 LS2

LIMITSWITCH

CLUTCH

24 VDC

GND

CARRIAGE BEGINSTO RETRACT

M2ON


71

Step 4: Traverse Retracted/LS1 Activated, Cycle Ends

When the carriage reaches the hard stops at the BOT position, limit switch LS1 is activated. The LS1 signal is used by the PLC to de-energize the motor. The traverse axis is in the home position shown in fi gure 69. The sequence just described is summarized by the sequence diagram in fi gure 70.

Figure 69. Step 4: Traverse Retracted/LS1 Activated, Cycle Ends


Step Input Action Output Action

INPUTS OUTPUTS

Sta

rt P

B

Sto

p P

B

LS2

LS1

M1

M2

0 Start Condition 0 1 0 1 0 0

1 Receive Start Input Extend Traverse 1/0 1

2 Traverse Extended Motor Stop 1 0 0

3 Receive Input Retract Traverse 1/0 1

4 Traverse Retracted Cycle Ends 0 1 0

End Condition 0 1 0 1 0 0

Figure 70. Sequence Diagram

LS1 ON

M2OFF


72

SKILL 6 DESIGN A PLC PROJECT THAT SEQUENCES A NON-SERVO ELECTRIC TRAVERSE AXIS

Procedure Overview

In this procedure, you will design a PLC project that sequences the non-servo electric traverse axis. This will familiarize you with the operation of the traverse axis and how to program its operation.

1. Design a PLC program to sequence a non-servo traverse axis given the following information.

The general sequence, I/O diagram, and power diagrams are as follows: General Sequence

1) Pressing the start pushbutton causes motor starter M1 to energize, which extends the traverse toward the EOT position.

2) Once the traverse is fully extended, LS2 on, motor starter M1 is de-ener-gized, turning off the motor. The part is then manually removed from the carriage.

3) Pressing the Start pushbutton again causes motor starter M2 to energize. The carriage should move toward the BOT position.

4) When the carriage is fully retracted, LS1 on, motor starter M2 is de-ener-gized, turning the motor off.

Special Conditions• The traverse axis should be manually positioned at the BOT position using the motor starter manual overrides. • A valve body should be manually placed in the recess on the carriage. • The Start pushbutton lamp should be on solid when the motor is running and off when it is not.


73

Figure 71. I/O Diagram

Figure 72. Power Diagram

I0.0

Q5.0I1.6

PB

TRAVERSERETRACTED

I1.7

I/O DIAGRAMINPUTS OUTPUTS

M1

LS2

LS1

START INPUT

TRAVERSEEXTENDED

Q5.1 M2

FORWARD MOTORSTARTER

REVERSE MOTORSTARTER

Q4.0ACTIVE LAMP

REVERSE

M1

M1

M2

M2

FORWARD

CARRIAGE

LIMITSWITCH

REV FWD

LS1 LS2

LIMITSWITCH

CLUTCH

24 VDC

GND


74



INPUTS OUTPUTS

Sta

rt P

B (

I0.0

)

Sto

p P

B (

I0.1

)

LS2

(I1.

6)

LS1

(I1.

7)

M1

(Q5.

0)

M2

(Q5.

1)


1 Receive Start Input Extend Traverse 1/0 1

2 Traverse Extended Motor Stop 1 0 0

3 Receive Input Retract Traverse 1/0 1

4 Traverse Retracted Cycle Ends 0 1 0






C. Start the SIMATIC Manager. 3. Perform the following substeps to create a project.

A. Create a Project named L4S6XXX where XXX represents your initials.

B. Create an S7 Station object for the station and confi gure its hardware.

C. Open Organizational Block OB1.

D. Enter the program that you developed in Step 1 into Organizational Block OB1.

E. Save OB1. 4. Locate the 87-MS2 Gauging station. 5. If the 87-MS2 Gauging station is connected to another 87-MS station,

separate the stations. If the 87-MS2 Gauging station is already disconnected, continue to Step 6.


75






Tie up long hair






7. Plug the station’s power cable into a wall outlet. 8. Perform the following substeps to power up the 87-MS2 Gauging station.



C. Turn the station’s Main Power Switch to the On position. 9. Perform the following substeps to download the project to the PLC.

A. Reset the PLC.

B. Download the SIMATIC 300 Station object to the PLC.


C. Click Yes on the dialog to complete a warm restart. 10. Go online with the processor and monitor the OB1 Block. 11. Press the Output Power pushbutton to enable the PLC’s outputs.


76

12. Perform the following substeps to test the operation of the program.

A. Manually operate the motor starter manual overrides to position the traverse axis carriage at the BOT position.

B. Manually place a valve body in the recess provided.

Make sure that the valve is oriented as shown in fi gure 75.

Figure 75. Valve Body in Place


The following sequence should occur:• Motor starter M1 should energize. • The carriage should move toward the EOT position until it strikes the hard stop and activates limit switch LS2. • Motor starter M1 should de-energize, the motor should stop.• The Start button lamp should be on during operation and turn off when the sequence is complete.

D. Manually remove the part from the traverse axis.

E. Press and release the Start pushbutton.

The following sequence should occur:• The Start pushbutton lamp should turn on solid during operation. • Motor starter M2 should energize. • The carriage should move toward the BOT position until it strikes the hard stop and activates limit switch LS1. • Motor starter M2 should de-energize and the motor should stop. • The Start pushbutton lamp should turn off.

F. Repeat substeps B through E until you are familiar with the operation of the traverse axis.

13. Print out a copy of the ladder logic program and place it in your portfolio. It will be used in your assessment.

14. Perform the following substeps to shut down the 87-MS2 Gauging station.

A. Close the LAD/STL/FBD Program Editor.



D. Turn the 87-MS2’s Main Power switch to Off.

E. Perform a lockout/tagout on the system’s electrical power source.


77

OBJECTIVE 8 DESCRIBE A SEQUENCE OF OPERATION OF A PART REJECT MODULE

A part reject module, shown in fi gure 76, is a device that removes a part from the manufacturing process after a test has been performed on the part and found it bad. A simple reject module could consist of two double-acting cylinders, one to lift the part from its holding fi xture on which it is traveling and one to move the part to a reject bin, as shown in fi gure 76. In this example, the reject cylinder uses magnetic reed sensors to indicate it’s retracted and extended positions. An addi-tional pneumatic actuator may be included to pass good parts to another part of the station for further processing.

Figure 76. Part Reject Module Construction

A typical sequence of operation of a part reject module follows.

PART REJECT MODULE SEQUENCE

STEP INPUT OUTPUT

1 Receive Start Input (S1 on) Extend lift cylinder (SOL3 on, lift timer starts)

2 Lift cylinder extended (Timer done) Extend reject cylinder (SOL1 on)

3 Reject cylinder extended (MR2 on) Retract reject cylinder

4 Reject cylinder retracted (MR1 on) Retract lift cylinder (Lift timer starts)

5 Lift cylinder retracted (Timer done) Cycle ends

Figure 77. Part Reject Module Sequence of Operation

MAGNETICREED SWITCHES

REJECTCYLINDER

(SOL1)PART

REJECTBIN

LIFTCYLINDER

(SOL3)

MR1MR2


78

Initial Condition

The home position of the part reject module is where both the Lift and Reject cylinders are retracted, as shown in fi gure 78.

Figure 78. Initial Condition

SOL1

REJECT CYLINDER

SOL3LIFT CYLINDER

CYLINDERRETRACTED

MR1

CYLINDEREXTENDED

MR2

QUICKEXHAUST

FROMSOURCE

MR1 ON

REJECTCYLINDER

RETRACTED

LIFTCYLINDER

RETRACTED


79

Step 1: Receive Start Input, Lift Cylinder Extends

In this step, the PLC controlling the part reject module receives an input to start the sequence. The input may be from another workstation, an operator, or the robot tending the module. After receiving the input signal, the PLC energizes SOL3 to extend the Lift cylinder and lift the part, as shown in fi gure 79.

Figure 79. Step 1: Receive Start Input, Lift Cylinder Extends

SOL1

REJECT CYLINDER

SOL3 LIFT CYLINDER

CYLINDERRETRACTED

MR1

CYLINDEREXTENDED

MR2

QUICKEXHAUST

FROMSOURCE

LIFTCYLINDERBEGINS TO

EXTEND


80

Step 2: Lift Cylinder Extended, Reject Cylinder Extends

When the Lift cylinder is fully extended, the PLC outputs a signal to energize SOL1 to extend the reject cylinder. This moves the cylinder away from MR1.

A timer is used as an interlock for this step in the PLC program. If the timer has not timed out, indicating that the Lift cylinder is fully extended, the Reject cylinder cannot extend.

Figure 80. Step 2: Lift Cylinder Extended, Reject Cylinder Extends

SOL1REJECT CYLINDER

SOL3 LIFT CYLINDER

CYLINDERRETRACTED

MR1

CYLINDEREXTENDED

MR2

QUICKEXHAUST

FROMSOURCE

LIFTCYLINDER

FULLYEXTENDED

REJECTCYLINDERBEGINS TO

EXTEND


81

Step 3: Reject Cylinder Extended, Reject Cylinder Retracts

When the Reject cylinder extends, it pushes a part into a reject area of the station. When it has fully extended, it energizes magnetic reed switch MR2. After the PLC receives this input, it de-energizes SOL1 to retract the Reject cylinder, as shown in fi gure 81.

Figure 81. Step 3: Reject Cylinder Extended, Reject Cylinder Retracts

SOL1

REJECT CYLINDER

SOL3 LIFT CYLINDER

CYLINDERRETRACTED

MR1

CYLINDEREXTENDED

MR2

QUICKEXHAUST

FROMSOURCE

REJECT CYLINDERBEGINS TO RETRACT

PART PUSHED INTOREJECT BIN

MR1OFF

MR2ON


82

Step 4: Reject Cylinder Retracted, Lift Cylinder Retracts

When the Reject cylinder has fully retracted, it energizes magnetic reed switch MR1. The PLC uses this input to de-energize SOL3 to retract the Lift cylinder, as shown in fi gure 82. Again, a timer is used to give the lift cylinder time to retract.

Figure 82. Step 4: Reject Cylinder Retracted, Lift Cylinder Retracts

SOL1

REJECT CYLINDER

SOL3

LIFT CYLINDER

CYLINDERRETRACTED

MR1

CYLINDEREXTENDED

MR2

QUICKEXHAUST

FROMSOURCE

REJECTCYLINDER

RETRACTED

LIFT CYLINDERBEGINS TO RETRACT

MR1ON

MR2OFF


83

Step 5: Lift Cylinder Retracted, End of Cycle

When the Lift cylinder fully retracts and the cycle ends, the part reject module is back in the home position shown in fi gure 83. The cycle will repeat when the PLC receives the input signal again.

Figure 83. Step 5: Lift Cylinder Retracted, End of Cycle

SOL1

REJECT CYLINDER

SOL3

LIFT CYLINDER

CYLINDERRETRACTED

MR1

CYLINDEREXTENDED

MR2

QUICKEXHAUST

FROMSOURCE

LIFTCYLINDER

RETRACTED


84

As long as there is a part in the part reject module and the Lift and Reject cylinders are fully retracted, the module will operate the next time the start input is energized.

The sequence just described is summarized by the sequence diagram in fi gure 84.



INPUTS OUTPUTS

Sta

rt P

B

Sto

p P

B

MR

1

MR

2

SO

L1

SO

L3


1 Receive Start Input Extend Lift Cylinder 1/0 1

2 Lift Cylinder Extended Extend Reject Cylinder 1

3 Reject Cylinder Extended Retract Reject Cylinder 1 1 0

4 Reject Cylinder Retracted Retract Lift Cylinder 0 0 0

5 Lift Cylinder Retracted Cycle Ends




85

SKILL 7 DESIGN A PLC PROJECT THAT SEQUENCES A PART REJECT MODULE

Procedure Overview

In this procedure, you will design a PLC project that sequences a part reject module. This will familiarize you with the operation and programming of a part reject module.

1. Design a PLC project to control a part reject module given the following information.

The general sequence, I/O diagram, power diagrams as follows: General Sequence

1) Pressing the Start pushbutton causes the Lift cylinder to extend, lifting a valve body off of the carriage. It also causes a 500 ms timer to start.

2) After the Lift cylinder has extended, indicated by the timer timing out, the Reject cylinder should extend to push the valve body into the bin.

3) After the Reject cylinder has extended (MR2 on), the valve body should be pushed into a bin and the cylinder should be retracted.

4) After the Reject cylinder has retracted (MR1 on), the Lift cylinder should start to retract and a 500 ms timer should start.

5) After the Lift cylinder has been retracted, which is indicated by the completion of the timer, the part reject module is in its home position.

Special Conditions• The traverse axis should be manually positioned at the EOT position using the motor starter manual overrides. • A valve body should be manually placed in the recess on the carriage.


I0.0

Q4.5I1.2

PB

REJECT CYLINDER RETRACTED

I1.3

I/O DIAGRAMINPUTS OUTPUTS

REJECT CYLINDER (SOL1)

MR1

MR2

START INPUT

REJECT CYLINDER EXTENDED Q5.6

LIFT CYLINDER (SOL3)

Q4.0ACTIVE LAMP


86




INPUTS OUTPUTSS

tart

PB

(I0

.0)

Sto

p P

B (

I0.1

)

MR

1 (I

1.2)

MR

2 (I

1.3)

SO

L1 (

Q4.

5)

SO

L3 (

Q5.

6)


1 Receive Start Input Extend Lift Cylinder 1/0 1




5 Lift Cylinder Retracted Cycle Ends







A. Create a Project named L4S7XXX where XXX represents your initials.



S1

REJECT CYLINDER

S3

LIFT CYLINDER

CYLINDERRETRACTED

MR1

CYLINDEREXTENDED

MR2

QUICKEXHAUST

FROMSOURCE


87

D. Enter the program that you developed in Step 1 into Organizational Block OB1.


separate the stations. If the 87-MS2 Gauging station is already disconnected, continue to step 6.






Tie up long hair






7. Connect an air supply line to the station’s air manifold quick connect. 8. Plug the station’s power cable into a wall outlet. 9. Perform the following substeps to power up the 87-MS2 Gauging Station.






F. Turn the station’s Main Power Switch to the On position. 10. Perform the following substeps to download the project to the PLC.

A. Reset the PLC.





88

13. Perform the following substeps to test the operation of the program.

A. Use the motor starter manual overrides to place the traverse axis at the EOT position.

Limit switch LS2 should be activated and the carriage should be against the hard stops, as shown in fi gure 89.

B. Make sure a reject bin is in place, as shown in fi gure 89.

C. Manually place a valve body in the recess provided on the carriage, as shown in fi gure 89.

Figure 89. Carriage, Reject Bin, and Valve Body in Place

REJECT BIN

CARRIAGE

VALVEBODY

REJECTCYLINDER


89


The following sequence should occur:• The lift cylinder should raise the part.• After the lift cylinder has fully extended the reject cylinder should extend, pushing the part into the reject bin.• After the reject cylinder has fully extended, both the reject cylinder and lift cylinder should retract.• This successfully completes one cycle of the part reject module.

E. Manually place a valve body in the recess provided on the carriage.

F. Press and release the Start pushbutton.

The cycle should repeat.

G. Repeat substeps D through F until you are familiar with the operation of the part reject module.



A. Close the LAD/STL/FBD Editor.





F. Perform a lockout/tagout on the system’s pneumatic power source.


90


1. A non-servo traverse axis includes a motor-driven carriage and two end-of-travel _____.

2. The traverse axis must be in its _____ position before a sequence can start.

3. A fi xture is typically attached to the _____ of the traverse axis to hold the parts being transported.

4. A part reject module removes a part from the manufacturing process after a _____ has been performed on the part and found it bad.

5. A simple reject module may consist of two cylinders, one to _____ the part and another to push the part into a reject bin.

6. Cylinders used in part reject modules use sensors such as _____ to indicate when it is extended and retracted.


91

SEGMENT 4STATION SEQUENCING

OBJECTIVE 9 DESCRIBE A SEQUENCE OF OPERATION OF A GO NO-GO GAUGING STATION

Some Go No-Go Gauging stations use a material handling device such as a traverse axis to move parts from one point to another in addition to performing the inspection process. The parts can either be inspected while stationary or while in motion using one or more sensors. The sensor outputs are used to determine if the part is good (Go) or bad (No-Go). If the part is good, it is usually transferred to another station for further processing. If the part is bad, it is usually removed from the station and scrapped or reworked.

An example of a Go No-Go gauging station is shown in fi gure 90. This station is designed to inspect a port location and height of a valve body. It consists of a number of independent devices, controlled by a single PLC, that work together to accomplish the inspection task.

Figure 90. Construction of a Go No-Go Gauging Station

TRAVERSEAXIS

TRANSFERCYLINDER

INSPECTIONSENSORS

REJECTCYLINDER

LIFTCYLINDER


92

The Go No-Go Gauging Station performs a sequence of operation under the control of a PLC. The station is a combination of the traverse axis, reject module and transfer module. An example is shown in fi gure 91. Note that the two separate sequences are shown, one for a good part and another for a bad part.

GO NO-GO GAUGING STATION SEQUENCE -GOOD PART

STEP INPUT ACTION OUTPUT ACTION

1 Receive Start Input (S1 on) Extend Traverse (M1 on)

2 Traverse Extended (LS2 on) Motor Off/Lift Cylinder Extends (SOL3 on, Lift timer starts)

3 Lift Cylinder Extended (Timer done) Extend Transfer Cylinder (SOL2A on)

4 Transfer Cylinder Extended (MR4 on) Retract Transfer Cylinder (SOL2B) on)

5 Transfer Cylinder Retracted (MR3 on) Retract Lift Cylinder (Lift timer started)

6 Lift Cylinder Retracted (Timer done) Retract Traverse (M2 on)

7 Traverse Retracted (LS1 on) Motor Off/Cycle Ends

GO NO-GO GAUGING STATION SEQUENCE -BAD PART

STEP INPUT ACTION OUTPUT ACTION

1 Receive Start Input (S1 on) Extend Traverse (M1 on)

2 Traverse Extended (LS2 on) Motor Off/Lift Cylinder Extends (SOL3 on, Lift timer starts)

3 Lift Cylinder Extended (Timer done) Extend Reject Cylinder (SOL1 on)

4 Reject Cylinder Extended (MR2 on) Retract Reject Cylinder

5 Reject Cylinder Retracted (MR1 on) Retract Lift Cylinder (Lift timer started)

6 Lift Cylinder Retracted (Timer done) Retract Traverse (M2 on)

7 Traverse Retracted (LS1 on) Motor Off/Cycle Ends

Figure 91. Go No-Go Station Sequences


93

When a part is initially placed on the station, a photoelectric sensor (PE1) performs the fi rst inspection. It looks for the location of the left-most port. If the sensor’s input goes high, the port is not detected, which causes the PLC to reject the part. If the sensor’s input does not go high, the port is located and the part passes that portion of the inspection.

Figure 92. Port Inspection

PE1LOOKS FORLEFT-MOST

PORT

PART

CARRIAGE


94

As the part carriage moves away from the BOT position, a tab mounted on the carriage activates an inductive sensor (IND1). This sensor is used as an input to the PLC that the part is in proper position to be measured by the gauging sensor, which in this example is an ultrasonic sensor, US1. The sensor is active while the part travels underneath it. The sensor’s input is used by the PLC logic to determine if the part is good (Go) or a reject (No-Go). If the input does not go high, the part is not detected and it is outside the sensor’s window boundaries. This means it is not of the proper height and therefore not a good part and will be rejected. If the input does go high, the part is detected and therefore is within the sensor’s window boundaries and passes that portion of the inspection.

Figure 93. Height Inspection

If the part passes both portions of the inspection, port location and height, then it will be transferred on to the next station for processing. If the part fails either portion of the inspection, it will be rejected.

IND1 DETECTSCARRIAGE ANDTRIGGERS US1

US1 MEASURESPART HEIGHT

GOOD PARTSARE TRANSFERRED

FOR FURTHERPROCESSING

BAD PARTSARE REJECTED


95

SKILL 8 DESIGN A PLC PROJECT THAT SEQUENCES A GO NO-GO GAUGING STATION

Procedure Overview

In this procedure, you will design a PLC project to sequence the Go No-Go Gauging station. This will familiarize you with the operation and programming of a Go No-Go Gauging station.

1. Design a PLC project that sequences a Go No-Go Gauging Station given the following information.

The general sequence, I/O diagram, power diagram, and sequence diagram are as follows:

General Sequence

1) When a part is placed on the carriage, the photoelectric sensor, PE1 either detects the presence of left most hole on the side with two holes, in which it does not activate its input, or it does not see the hole, in which case it does activate its input. If the input is high, then the part is bad (No-Go). Pressing the Start pushbutton causes motor starter M1 to energize. The carriage should move toward the EOT position. When the carriage acti-vates inductive sensor IND1, the valve body is under the ultrasonic sensor. The ultrasonic sensor measures the valve body’s height as it passes under-neath. If US1’s input does not go high, the part is bad (No-Go). If PE1 does not go high but US1 does, the part is good (Go). The carriage continues on to the EOT position.

2) The carriage actuates LS2 when it reaches the EOT position. The PLC de-energizes motor starter M1 to turn off the motor.

3) After the motor has stopped, the Lift cylinder extends, lifting the valve body off of the carriage. A 500 ms timer is used to give the cylinder time to extend.

4) After the Lift cylinder has extended, either the Reject (No Go) or Transfer (Go) cylinder should extend to push the valve body into a bin.

5) After the Reject or Transfer cylinder has extended, it should be retracted.

6) After the Reject or Transfer cylinder is retracted, the Lift cylinder should retract, again using a 500 ms timer to give the cylinder time to retract.

7) After all cylinders have retracted, motor starter M2 energizes. The carriage should move toward the BOT position.

8) The carriage reaches the BOT position, activating limit switch LS1. Motor starter M2 is de-energized, turning off the motor.

Special Conditions• The traverse axis should be manually positioned at the BOT position using the motor starter manual overrides. • A valve body should be manually placed in the recess on the carriage. • Pressing the Stop pushbutton at any time should cause the sequence to stop


96

(or halt) at the end of its current step. Pressing the Start pushbutton should resume the sequence. • The cycle should repeat when a new part is placed onto the traverse axis and the Start pushbutton is pressed.• The Start pushbutton should be on solid during operation and should turn off after the cycle ends.


I/O DIAGRAM

I0.0 Q4.0

Q4.5

Q4.6

Q4.7

Q5.0

Q5.1

I0.1

START

I1.0

I1.1

I1.7

LS1

ACTIVELAMP

PART REJECT EXTEND(SOL1)

PART TRANSFER EXTEND(SOL2A)

PART TRANSFER RETRACT(SOL2B)

TRAVERSE FORWARDCONTACTOR

TRAVERSE REVERSECONTACTOR

PB1

PB2

I1.6

LS2

I1.2

MR1

I1.3

MR2

I1.4

MR3

I1.5

MR4

TRAVERSEAXIS BOT

TRAVERSEAXIS EOT

REJECT CYLINDERRETRACTED

REJECT CYLINDEREXTENDED

TRANSFER CYLINDERRETRACTED

TRANSFER CYLINDEREXTENDED

I2.4

PE1PORT NOTDETECTED

Q5.6

PART LIFT EXTEND(SOL3)

STOP

RESET

AUTO

I2.2

IND1PART HEIGHT

READING

I2.3

US1PART HEIGHT

MEASUREMENT

M1

M2


97


SOL2A

TRANSFER CYLINDER

SOL3

LIFT CYLINDER

CYLINDERRETRACTED

MR3

CYLINDEREXTENDED

MR4

QUICKEXHAUST

SOL1

REJECT CYLINDER

CYLINDERRETRACTED

MR1

CYLINDEREXTENDED

MR2

REVERSE

M1

M1

M2

M2

FORWARD

US1

CARRIAGE

LIMITSWITCH

REV FWD

PE1

LS1 LS2

LIMITSWITCH

CLUTCH

24 VDC

GND

SOL2B

FROMSOURCE

IND1


98

GO NO-GO GAUGING STATION SEQUENCE- GOOD PART


INPUTS OUTPUTS

Sta

rt P

B (

I0.0

)

Sto

p P

B (

I0.1

)

MR

1 (1

.2)

MR

2 (1

.3)

MR

3 (1

.4)

MR

4 (1

.5)

LS2

(1.6

)

LS1

(1.7

)

IND

1 (I

2.2)

US

1 (I

2.3)

PE

1 (I

2.4)

SO

L1 (

Q4.

5)

SO

L2A

(Q

4.6)

SO

L2B

(Q

4.7)

SO

L3 (

Q5.

6)

M1

(Q5.

0)

M2

(Q5.

1)

0 Start Condition 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0

1 Receive Start Input Extend Traverse 1/0 1 1 1

2 Traverse Extended Motor Stop/Extend Lift Cylinder 1 0 0 1 0

3 Lift Cylinder Extended Extend Transfer Cylinder 1

4 Transfer Cylinder Extended Retract Transfer Cylinder 0 1 0 1

5 Transfer Cylinder Retracted Retract Lift Cylinder 1 0 0 0

6 Lift Cylinder Retracted Retract Traverse 1

7 Traverse Retracted Motor Off/Cycle Ends 0 1 0

End Condition 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0

GO NO-GO GAUGING STATION SEQUENCE- BAD PART


INPUTS OUTPUTS

Sta

rt P

B (

I0.0

)

Sto

p P

B (

I0.1

)

MR

1 (1

.2)

MR

2 (1

.3)

MR

3 (1

.4)

MR

4 (1

.5)

LS2

(1.6

)

LS1

(1.7

)

IND

1 (I

2.2)

US

1 (I

2.3)

PE

1 (I

2.4)

SO

L1 (

Q4.

5)

SO

L2A

(Q

4.6)

SO

L2B

(Q

4.7)

SO

L3 (

Q5.

6)

M1

(Q5.

0)

M2

(Q5.

1)

0 Start Condition 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0

1 Receive Start Input Extend Traverse 1/0 1 0 1 1

2 Traverse Extended Motor Stop/Extend Lift Cylinder 1 0 0 0 1 0






End Condition 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0






A. Create a Project named L4S8AXXX where XXX represents your initials.



D. Enter the program that you developed in step 1 into Organizational Block OB1.


99








Tie up long hair








B. Remove the lockout/tagout device from the electric lockout.

C. Remove the lockout/tagout device from the pneumatic lockout.




A. Reset the PLC.





100

13. Perform the following substeps to test the operation of the program. You will need good and bad valve bodies to test the operation of the program.

Ask your instructor to provide you with the parts.

A. Use the motor starter manual overrides to place the traverse axis at the BOT position. Limit switch LS1 should be activated.

B. Make sure a bin is in place for both the reject and transfer sequences.

C. Manually place a good valve body in the recess provided on the carriage in the orientation in fi gure 98.

Figure 98. Valve Body in Place


101

D. Press and release the Start pushbutton.• The following sequence should occur:• The photoelectric sensor should check for the port and determine the part is a go.• The traverse axis should move toward the EOT position. • The ultrasonic sensor should make a measurement on the part as it passes under the sensor and the PLC logic should determine that the part is a go.• After the traverse axis reaches the EOT position, the motor should stop.• After the motor has stopped, the Lift cylinder should extend• After the Lift cylinder has extended, the Transfer cylinder should extend• The Transfer cylinder should retract• The Lift cylinder should retract• Motor starter M2 should energize and the carriage should move toward the BOT position. • When the carriage reaches the BOT position, LS1 should energize and the motor should turn off.

E. Manually place a bad valve body in the recess provided on the carriage in the orientation shown in fi gure 109. For this skill, use a bad valve body with ports.

A bad valve body is shorter than a good valve body and may not have ports.


The following sequence should occur:• The photoelectric sensor should check for the port and determine the part is a go.• The traverse axis should move toward the EOT position. • The ultrasonic sensor should make a measurement on the part as it passes under the sensor and the PLC logic should determine that the part is a no-go.• After the traverse axis reaches the EOT position, the motor should stop.• After the motor has stopped, the Lift cylinder should extend• After the Lift cylinder has extended, the Reject cylinder should extend• The Reject cylinder should retract.• The Lift cylinder should retract.• Motor starter M2 should energize and the carriage should move toward the BOT position. • When the carriage reaches the BOT position, LS1 should energize and the motor should turn off.

G. Manually place a good valve body in the recess provided on the traverse carriage, but this time turn the valve body so the side with two holes faces away from PE1.


102

H. Press and release the Start pushbutton.

The following sequence should occur:• The photoelectric sensor should check for the port and determine the part is a no-go.• The traverse axis should move toward the EOT position. • The ultrasonic sensor should make a measurement on the part as it passes under the sensor and the PLC logic should determine that the part is a Go.• After the traverse axis reaches the EOT position, the motor should stop.• After the motor has stopped, the Lift cylinder should extend• After the Lift cylinder has extended, the Reject cylinder should extend• The Reject cylinder should retract.• The Lift cylinder should retract.• Motor starter M2 should energize and the carriage should move toward the BOT position. • When the carriage reaches the BOT position, LS1 should energize and the motor should turn off.



A. Close the LAD/STL/FBD Editor.







103

OBJECTIVE 10 DESCRIBE THE OPERATION OF A GO NO-GO GAUGING STATION WITH MANUAL/AUTO/RESET FUNCTIONS

Traditional operator panels usually include 2-position or 3-position selector switches to select the mode of operation, as shown in fi gure 99. Some of the modes that can be selected are Off, Manual, Automatic, and Reset.

Figure 99. Operator Panel with Selector Switches

Automatic

Selecting the automatic mode causes the PLC program to disable the manual functions and enable the automatic functions. This is usually done by disabling a manual function or function block and enabling an automatic function or function block.

After automatic mode is selected, certain initial conditions are usually required to be satisfi ed before the station’s sequence can begin. These initial conditions are input signals monitored by the PLC to verify that the station’s actuators are in the home position and to verify that a part is present and ready to be processed. If the station’s actuators are not in the proper position, a visual indicator is usually displayed on the operator panel to indicate that the station is not in its home posi-tion. If the station’s actuators are not homed, the operator must either switch to manual mode and reposition the actuators, or initiate a reset function to home the station.

After the machine is homed and the automatic mode is selected, pressing a start pushbutton causes the station to perform its sequence automatically. After the sequence has been completed, the station repeats the cycle.

SELECTORSWITCH


104

Manual

Selecting the manual mode causes the PLC program to enable the machine’s manual functions. This is usually done in program logic by enabling a function or function block containing the manual operations while disabling functions and/or function blocks supporting the machine’s other operating modes.

Placing a machine in manual mode enables the user to move the machine’s actuators on an as needed basis and is rarely used for production purposes. Because of this, the manual mode is usually associated with maintenance operations. Main-tenance personnel may use the manual mode to: test the operation of a machine, make adjustments to the machine and/or its sensors, or to recover from a machine malfunction. There are two versions of manual operation: standard manual opera-tion and step.

• Manual (traditional) - In this version of manual operation, turning the selector switch to the Manual position typically enables pushbuttons and/or other manual operators on the operator panel to be used to manipulate the machine’s actuators. In the case of a gauging station, for example, the oper-ator panel (or HMI) could have two pushbuttons for each of the station’s cylinders, one to make the actuator extend and one to make it retract. • Step - In this version of manual operation, a pushbutton or other manual operator is used to step the machine through the steps of its sequence, one step at a time. In the case of a pick and place feeding application, pressing the pushbutton the fi rst time would cause the system’s feed cylinder to extend. Pressing the pushbutton a second time would cause the manipula-tor’s Z-axis to extend, and so forth.


105

Reset

A reset function is often included in the PLC program to home the station’s actuators. The PLC program is designed to return all actuators to their start, or home positions when a selector switch is placed in the Reset position.

The reset function can be programmed to cause all of the actuators to return to their start positions at the same time or it can be programmed to return them in a sequence. Depending on the physical layout of the station, returning all of the actuators at the same time may cause some actuators to interfere with others. In this case, the reset function must be programmed to perform a reset sequence. Using a sequence causes the actuators to return to the home position in an order that prevents interference with other actuators.

For example, a Go No-Go Gauging station’s Reject, Transfer, and Lift cylin-ders are fully retracted. After the cylinders are retracted, the traverse axis is moved to its beginning-of-travel position where it is ready to receive a part, as shown in fi gure 100. The cylinders are retracted fi rst so that they don’t cause any interfer-ence when the carriage is moved. When all of the stations parts are in the home position, an indicator is provided on the operator panel. The indicator may be a dedicated Home lamp, or solid or fl ashing indicators on the panel’s pushbuttons.

Figure 100. Go No-Go Gauging Station

LS1ON

MR3ON

TRANSFERCYLINDER

RETRACTEDTRAVERSE

RETRACTED

REJECTCYLINDER

RETRACTED

MR1ON

LIFTCYLINDER

RETRACTED


106

SKILL 9 DESIGN A PLC PROJECT THAT PROVIDES MANUAL/ AUTO/RESET FUNCTIONS FOR A GO NO-GO GAUGING STATION

Procedure Overview

In this procedure, you will design a PLC project that provides manual, automatic, and reset functions for the go no-go gauging station. This will require you to modify the project that you developed in a previous skill. This will familiarize you with programming manual, auto, and reset functions.

1. Design a PLC project that provides Manual/Auto/Reset functions for a Go No-Go Gauging station given the following information.

The general sequence, I/O diagram, power diagram, and sequence diagram are as follows:

General Sequence

1) In automatic mode, the program should work as it did in the previous skill.

2) When manual mode is selected, pressing the Start pushbutton causes the station to perform the next step of its sequence and stop. Each press of the Start pushbutton causes the next step to be performed until the cycle is complete.

3) When reset is selected:• The lift cylinder should retract using a 500 ms timer to verify it has had time to retract. • After it has retracted, the reject cylinder and transfer cylinder should retract at the same time.• When all of the cylinders have retracted, the traverse axis should move to the BOT position. • When all of the pneumatic actuators are retracted, and the traverse axis is in the BOT position, the lamp on the start pushbutton should turn off.


107


I/O DIAGRAM

I0.0 Q4.0

Q4.5

Q4.6

Q4.7

Q5.0

Q5.1

I0.1

START

I1.0

I1.1

I1.7

LS1

ACTIVELAMP

PART REJECT EXTEND(SOL1)

PART TRANSFER EXTEND(SOL2A)

PART TRANSFER RETRACT(SOL2B)

TRAVERSE FORWARDCONTACTOR

TRAVERSE REVERSECONTACTOR

PB1

PB2

I1.6

LS2

I1.2

MR1

I1.3

MR2

I1.4

MR3

I1.5

MR4

TRAVERSEAXIS BOT

TRAVERSEAXIS EOT

REJECT CYLINDERRETRACTED

REJECT CYLINDEREXTENDED

TRANSFER CYLINDERRETRACTED

TRANSFER CYLINDEREXTENDED

I2.4

PE1PORT NOTDETECTED

Q5.6

PART LIFT EXTEND(SOL3)

STOP

RESET

AUTO

I2.2

IND1PART HEIGHT

READING

I2.3

US1PART HEIGHT

MEASUREMENT

M1

M2


108


SOL2A

TRANSFER CYLINDER

SOL3

LIFT CYLINDER

CYLINDERRETRACTED

MR3

CYLINDEREXTENDED

MR4

QUICKEXHAUST

SOL1

REJECT CYLINDER

CYLINDERRETRACTED

MR1

CYLINDEREXTENDED

MR2

REVERSE

M1

M1

M2

M2

FORWARD

US1

CARRIAGE

LIMITSWITCH

REV FWD

PE1

LS1 LS2

LIMITSWITCH

CLUTCH

24 VDC

GND

SOL2B

FROMSOURCE

IND1


109

GO NO-GO GAUGING STATION SEQUENCE- GOOD PART


INPUTS OUTPUTS

Sta

rt P

B (

I0.0

)

Sto

p P

B (

I0.1

)

MR

1 (1

.2)

MR

2 (1

.3)

MR

3 (1

.4)

MR

4 (1

.5)

LS2

(1.6

)

LS1

(1.7

)

IND

1 (I

2.2)

US

1 (I

2.3)

PE

1 (I

2.4)

SO

L1 (

Q4.

5)

SO

L2A

(Q

4.6)

SO

L2B

(Q

4.7)

SO

L3 (

Q5.

6)

M1

(Q5.

0)

M2

(Q5.

1)

0 Start Condition 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0

1 Receive Start Input Extend Traverse 1/0 1 1 1

2 Traverse Extended Motor Stop/Extend Lift Cylinder 1 0 0 1 0

3 Lift Cylinder Extended Extend Transfer Cylinder 1

4 Transfer Cylinder Extended Retract Transfer Cylinder 0 1 0 1

5 Transfer Cylinder Retracted Retract Lift Cylinder 1 0 0 0



End Condition 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0

GO NO-GO GAUGING STATION SEQUENCE- BAD PART


INPUTS OUTPUTS

Sta

rt P

B (

I0.0

)

Sto

p P

B (

I0.1

)

MR

1 (1

.2)

MR

2 (1

.3)

MR

3 (1

.4)

MR

4 (1

.5)

LS2

(1.6

)

LS1

(1.7

)

IND

1 (I

2.2)

US

1 (I

2.3)

PE

1 (I

2.4)

SO

L1 (

Q4.

5)

SO

L2A

(Q

4.6)

SO

L2B

(Q

4.7)

SO

L3 (

Q5.

6)

M1

(Q5.

0)

M2

(Q5.

1)

0 Start Condition 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0

1 Receive Start Input Extend Traverse 1/0 1 0 1 1

2 Traverse Extended Motor Stop/Extend Lift Cylinder 1 0 0 0 1 0






End Condition 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0






A. Open Project L4S8AXXX that was created in a previous skill.

B. Click the Save As button on the toolbar to save the project with a new name.

The Save As dialog should open.

C. Enter the name L4S9XXX where XXX represents your initials.


110

D. Click OK on the dialog to create the project.

E. Fully expand the project tree.

F. Select the Blocks folder so that its contents are displayed in the right-hand side project window.

G. Open Organizational Block OB1 by double-clicking its icon.

H. Modify OB1 with the logic that you developed in Step1.

I. Save OB1. 4. Locate the 87-MS2 Gauging station. 5. If the 87-MS2 Gauging station is connected to another 87-MS station,







Tie up long hair













A. Reset the PLC.




111

C. Click Yes on the dialog to complete a warm restart. 11. Go online with the processor and monitor the OB1 Block. 12. Press the Output Power pushbutton to enable the PLC’s outputs. 13. Perform the following substeps to test the operation of the program in the

automatic mode.

A. Make sure a reject bin is in place.

B. Use the motor starter manual override to place the traverse axis at the BOT position. Limit switch LS1 should be activated and the carriage should be against the hard stops.

C. Manually place a good valve body in the recess provided on the traverse axis in the correct orientation.

D. Set the Mode Selector switch to Auto.


The following sequence should occur:• The photoelectric sensor should check for the port and determine the part is a go.• The traverse axis should move toward the EOT position. The ultrasonic sensor should make a measurement on the part as it passes under the sensor and the PLC logic should determine that the part is a go.• After the traverse axis reaches the EOT position, the motor should stop.• After the motor has stopped, the Lift cylinder should extend• After the Lift cylinder has extended, the Transfer cylinder should extend• The Transfer cylinder should retract• The Lift cylinder should retract• Motor starter M2 should energize and the carriage should move toward the BOT position. • When the carriage reaches the BOT position, LS1 should energize and the motor should turn off.

14. Perform the following substeps to test the operation of the program in the manual mode.

A. Manually place a good valve body in the recess provided on the traverse axis.

B. Place the Mode Selector in the Manual position.


The traverse axis should move toward the EOT position. The photoelectric and ultrasonic sensors should check the part as it passes and the PLC logic should determine that the part is a go. When the carriage reaches the EOT position, limit switch LS2 should energize and the motor should turn off.


The Lift cylinder should extend, raising the valve body from the recess.


The Transfer cylinder should extend, pushing the part into the bin.


The Transfer cylinder should retract.


112

G. Press and release the Start pushbutton.

The Lift cylinder should retract.

H. Press and release the Start pushbutton.

The traverse axis should return to the BOT position. When the carriage reaches the BOT position, LS1 should energize and the motor should turn off.

15. Perform the following substeps to test the reset portion of the program. The Mode Selector should still be in the manual position.

A. Use the motor starter manual overrides to position the traverse axis at the EOT position.

B. Use the pneumatic valve manual overrides to extend the lift cylinder.

C. Use the pneumatic valve manual overrides to extend the transfer cylinder.

D. Use the pneumatic valve manual overrides to extend the reject cylinder.

E. Place the Mode Selector switch in the Reset position.

The following sequence should occur:• The lift cylinder should retract.• After it has retracted, the reject cylinder and transfer cylinder should retract at the same time.• When all of the cylinders have retracted, the traverse axis should move to the BOT position. • When all of the pneumatic actuators are retracted, and the traverse axis is in the BOT position, the lamp on the start pushbutton should be off.



A. Close the LAD/STL/FBD Program Editor.







113


1. Parts on a gauging station can be _____ while stationary or moving.

2. If a part is found bad, it is removed from the station and either _____ or reworked.

3. The PLC controlling the gauging station uses the input from the inspection process to determine whether to reject or _____ the part.

4. Operator panels typically include _____ to select the mode.

5. When a system is in automatic mode, certain _____ conditions must be met before the station’s sequence can begin.

6. Manual mode enables the user to move the machine’s actuators on an ______ basis.

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