manual electrical 1styr 09-25

ELECTRICAL, ELECTRONICS & COMPUTER SHOP

NATIONAL INSTITUTE OF TECHNOLOGY ROURKELA-769008

Table of Contents Sl. No. Name of the Job Page No.

1. Soldering and De-soldering practice 2 2. To make a Half-Wave & Full wave Rectifier Circuit and

Analyses the Wave Forms with Cathode Ray Oscilloscope (CRO).

9

3. TO make an electrical wiring for controlling two lamps from a switch board.

16

4. To make the electrical connection of a fluorescent lamp 19

5. To make electrical wiring for controlling different loads from a switch board.

23

6. To control a lamp from two positions and from multiple positions.

27

Electrical, Electronics and Computer Shop



JOB-1

AIM: Soldering and De-soldering practice Tools and Equipment Required: Sl. No. Name of the Tools Size Quantity

1. Insulated wire stripper 130 mm 1 nos. 2. Soldering Iron stand small 1 nos. 3. Soldering Iron 25 Watt, 230 V 1 nos. 4. De-soldering pump 180 mm 1 nos. 5. Neon Tester (0-500)V 1 nos.

Materials Required: Sl. No. Name of the Materials Rating/Size Quantity

1. Vero Board (100×150×1.6) mm 1 nos. 2. Soldering flux ISI mark As per requirement 3. Soldering wires Diameter (0.5-5) mm As per requirement 4. Connecting wires Single core, diameter

(0.5-5) mm, copper/ Aluminum

As per requirement

How to Practice Good Soldering Method?

Soldering is done in electronics constructions to join the components with the tracks of the PCB. The working performance of the circuit depends on the accuracy and perfection in the soldering. Actually it is an art to make a good circuit. Soldering requires skill and practicing the good soldering methods will help you to make a good working circuit. Here explains the methods of good soldering. Soldering requires Soldering Iron, Soldering Lead and Flux along with a PCB and component layout diagram.Figure 1 shows the standard soldering stand which is used to keep the soldering iron after use.


Figure 1. Soldering Stand

Selection of Good Soldering Iron:

Selection of the Soldering Iron (Figure 2) is very important. Soldering Iron is the electric device that heat up the solder lead and makes the joint. Many types of soldering irons are available, so select one with 15-25 watts. If the wattage of the Iron is too high, it may destroy the heat sensitive components or causes detachment of PCB tracks. Choose the Iron with a 3 pin cord. Earth connection is important to remove the stray current that accumulates in the iron tip. This is very important while soldering static sensitive components like CMOS ICs and MOSFETs.

Figure 2. Soldering Iron


Use the Better Soldering Wire: Solder lead joins the component leads with the PCB contacts firmly. The quality of the solder lead should be good enough to, make the soldering process perfect. Rosin core solder is a good choice shown in Figure 3. Do not use the Acid core solder used to solder electrical contacts and plumbing metal joints since the acid content will corrode the copper tracks of the PCB. Good solder contains 60% Tin and 40% Lead. Solder with 0.75 to 1mm diameter is good. Some makes of solder contains a core of flux inside.

Figure 3. Soldering Wire

Use Little Soldering Flux

Soldering flux is usually applied to the solder joints before soldering. The flux reduces the melting point of the lead so that the solder lead will melt easily and spread uniformly on the solder joint which is shown in Figure 4. Liquid type flux is better since it will not leave dirt after soldering. Fumes from the flux is toxic so do the soldering work in a well ventilated place and use an exhaust fan in the room.

Figure 4. Soldering Flux

http://www.elprocus.com/wp-content/uploads/2013/03/SOLDERING-LEAD.jpg

http://www.elprocus.com/wp-content/uploads/2013/03/SOLDETING-FLUX.jpg


A well maintained Tip can make the soldering easy

Dry Joint Colder Joint Good Solder Joint Figure 5. Typical good soldering

Good soldering requires clean soldering iron tip. If the soldering Iron is a newly purchased one, first apply a layer of lead before starting the soldering. This is called Tinning which will helps to transfer heat easily. After prolonged use, the tip will become dirty which will make the soldering process difficult. So before starting the soldering, clean the tip using a File or Sand paper and make it glowing. After cleaning, wipe the tip with moist cotton or sponge. Since the soldering process is intermittent, keep the soldering iron tip on a heat sink. An old porcelain fuse carrier can be used for this or purchase one soldering iron stand with heat sink. Figure 5 shows the example of good soldering on PCB. The front view of the vero board is shown in Figure 7 which is used for soldering purpose in the Electrical , Electronics and Computer shop at NIT Rourkela.

Figure 7. Vero Board

http://www.elprocus.com/wp-content/uploads/2013/03/DRY-JOINT.jpg


Top Tips in Soldering Process:

The following tips will help you to practice good soldering methods:

1. First clean the PCB joints well using a blade or knife to remove dirt and corroded materials. If the joint is dirty, the solder joints will be loose.

2. Clean the leads of components before placing on the PCB. 3. The leads will project out from the copper track side of PCB. Place

resistors slightly projecting from the surface of PCB to dissipate heat. 4. First solder resistors, then capacitors, diodes etc and finally

transistors and ICs. 5. Apply very little flux in the solder joints and make the soldering. The

soldering lead and the iron tip should be at an angle of 45 degree so as the make the solder flow easily.

6. Do not keep the soldering iron tip more than 3 seconds on the soldering joint when soldering CMOS components.

7. After soldering, check the solder joints carefully. Use a hand lens if needed. The joints should be conical, uniform and shiny.

8. If the solder joint is Dry, that will considerably affects the working of circuit. So double check all the joints and re-solder if necessary.

9. Cold solder is the term used to describe the solder joints without firm connection. The cold solder will appear as a ball over the solder joint. So if it appears remove the excess solder with the hot iron tip.

10. Trim the excess leads of the components with a Trimmer. 11. If static sensitive components are used, touch the soldering iron tip to

a metal object before soldering to remove the static charge accumulated at the tip.

12. Wires should be soldered firmly to prevent loose contact. Before soldering the wires, clean the bare wire with a blade to remove rust or dirt. Apply some solder to the wire tip and make the soldering.

13. After completing the soldering, double check the joints for any shorting of leads. This is essential for the transistors and ICs.

14. Clean the solder side of PCB using Spirit or PCB cleaning solution. 15. After connecting the power supply, just touch on the components. If

heat develops, disconnect the power supply immediately and check for any shorting.

16. If AC is used in the PCB, do not touch any points when connected to mains.

17. As a safety measure, wear a rubble foot wear during soldering. It is better to use a plastic sheet on the floor so that the foot will rest on the insulated sheet while soldering.


Desoldering In electronics, de-soldering is the removal of solder and components from a circuit board for troubleshooting, repair, replacement, and salvage. Specialized tools, materials, and techniques have been devised to aid in the de-soldering process.There are several effective methods for removing solder from a PCB hole. Excess solder filling a hole happens quite often. Usually, the clog is residual solder that occurs when an existing electronic component is de-soldered and removed. The de-soldering pump used to remove the excess solder from the PCB which is shown in Figure. 8.

Figure 8.De-soldering pump

To remove excess solder from a hole:

1. The printed circuit board is held in a vise or PCB holder 2. The tip of the de-soldering bulb is placed behind the hole and the

pump is squeezed 3. The tip of a heated soldering iron is pressed against the hole to melt

the solder 4. Keeping the pump against the hole, the pump is released (unsqueezed)

either with the soldering iron in place or just as the iron is being withdrawn. It is found that both techniques helpful depending on the size of the hole and amount of remaining solder. In either case, the molten solder is drawn into the de-soldering pump.


How to De-solder Step 1: Equipment De-soldering requires two main things: a soldering iron and a device to remove solder. Soldering irons are the heat source used to melt solder. Irons of the 15W to 25W range are good for most electronics/printed circuit board work. Anything higher in wattage and you risk damaging either the component or the board. Note that you should not use so-called soldering guns. These are very high wattage and generate most of their heat by passing an electrical current through a wire. Because of this, the wire carries a stray voltage that could damage circuits and components. The choice of your solder removing device is also important. There are two main ones; vacuum pumps (solder suckers) and solder wick. They both do the same thing, so what you use will depend on your personal opinion or experiences. I suggest keeping both on hand though, as you may find that each works well in different situations. Solder suckers usually look like large syringes. There is a spring loaded plunger, and a button to release it. The plunger is pushed down. When you want to suck up the solder, you position the nozzle over the molten solder and hit the button. The plunger moves up, creating a vacuum and sucking up the solder. Solder wick, on the other hand, has no moving parts. It looks like wick used in oil lamps, except that it is made of copper. To use it, you put the wick over the joint and heat it. One thing to note about solder wick is that it is expensive, and because it is expendable, a solder sucker may be a better choice if you plan to do a lot of de-soldering. I personally prefer to use a sucker to remove most of the solder, then finish up with the wick. Remember that when de-soldering, the resin in the solder and the coating on the board may releases fumes. These fumes are harmful to your eyes and lungs. Therefore, always work in a well ventilated area. Hot solder is also dangerous. Be sure not to let it splash around because it will burn you almost instantly. Eye protection is also advised. Step 2: Surface Preparation There isn't really too much to worry about when removing solder. Just make sure to get any grease, varnish or glue off the joint before you start heating. If you don't, you will probably foul the tip of your soldering iron pretty quickly. Step 3: Apply Heat Lay the iron tip so that it rests against both the component lead and the board. Normally, it takes one or two seconds to heat the component up enough to solder, but larger components and larger soldering pads on the board can increase the time. Step 4: Remove Solder


ELECTRICAL, ELECTRONICS& COMPUTER SHOP


JOB-02

Aim: To make a Half-Wave and Full Wave Rectifier Circuit and Analyses the Wave Forms with Cathode Ray Oscilloscope (CRO).

Tools and Equipment Required:

Sl. No.

Name of the Tools Size Quantity

1. Insulated screw Driver 150 mm 1 nos. 2. Insulated Combination plier 160 mm 1 nos. 3. Insulated wire stripper 130 mm 1 nos. 4. Soldering Iron 25 Watt, 230 V 1 nos. 5. Neon Tester (0-500)V 1 nos. 6. Cathode Ray Oscilloscope 200 MHz, 2 Ch,

100 ksa/s As per requirement


1. Vero Board (100×160×1.6) mm 1 nos. 2. Diode (1N4007) 1000V, 1 A 1 nos. 3. Resistance 1kΩ, 500 V, ¼ watt 1 nos. 4. Step-down Transformer 230/12-0-12V, 500 mA 1 nos. 5. Soldering flux ISI mark As per requirement 6. Soldering wires Diameter (0.5-5) mm As per requirement 7. Connecting wires Single core, diameter


As per requirement


Schematic Diagram of Half-Wave Rectifier:

Figure9. Half-wave rectifier circuit along with input and output waveform

Theory: A rectifier is an electrical device that converts alternating current(AC),which periodically reverses direction,to direct current(pulsating DC), which is only in one direction and the process is known as rectification .Whenonly one diode is used to rectify AC(by blocking the negative or positive portion of the wave form),the difference between the term diode and the term rectifier is merely one of usagei.e., the term rectifier describes a diode that is being used to convert AC to DC. Almost all low power rectifiers comprise a number of diodes in specific arrangement for more efficiently converting AC to DC than is possible with only one diode.

In half wave rectification, either the positive or negative half of the AC wave is passed, while the other half is blocked which is shown in Fig.9.Because only one half of the input waveform reaches the output, it is very inefficient if used for power transformer. Half wave rectification can be achieved with a single diode in a on phase supply, or with three diodes in a three- phase supply. The output DC voltage of a half wave rectifier can be calculated with the following Eqn.

𝐕𝐕𝐫𝐫𝐫𝐫𝐫𝐫 =𝐕𝐕𝐩𝐩𝐩𝐩𝐩𝐩𝐩𝐩𝟐𝟐 , 𝐕𝐕𝐝𝐝𝐝𝐝 =

𝐕𝐕𝐩𝐩𝐩𝐩𝐩𝐩𝐩𝐩𝛑𝛑

Procedure:

1. Connect the diode to the low voltage AC power supply as shown in Fig.9.Note that the resistor used to limit the current.


2. Connect channel-1(CH-1) of the oscilloscope to input and channel-2(CH-2) to output/load resistance of the circuit.

3. Switch on the oscilloscope and sinusoidal supply. 4. Sketch the input wave form. 5. Measure and record Time T,peak voltage V

p and peak voltage V

pp of the

input supply. 6. With DC couple adjusts the time-base and Y-amplifier sensitivity. 7. Sketch the wave form and label it show the periods when the diode is

conducting and those when it is not. Time T depends upon frequency of your power supply.

8. Measure and record Time T and peak voltage Vpof output wave form.

9. Confirm this Vpshould be very nearly equal to the peak voltage of

alternating supply. Observation: (Take observation from Oscilloscope) Input: Sl.No Time(T) 𝐕𝐕𝐩𝐩 𝐕𝐕𝐩𝐩𝐩𝐩 𝐕𝐕𝐫𝐫𝐫𝐫𝐫𝐫

Output: Sl. No. Time(T) 𝐕𝐕𝐩𝐩 𝐕𝐕𝐩𝐩𝐩𝐩 𝐕𝐕𝐫𝐫𝐫𝐫𝐫𝐫

Calculation: (Calculate the average DC voltage of designed circuit) Conclusion: Precautions: 1. Do not touch the heating part of the soldering iron. 2. Always keep the soldering iron in its stand. 3. All joints should be provided with insulation grip. Model Questions:

1. What is rectifier? 2. What is half wave rectifier? How does it work?




Full-Wave Rectifier Circuit Tools and Equipment Required: Sl. No. Name of the Tools Size Quantity

1. Insulated screw Driver 150 mm 1 nos. 2. Insulated Combination plier 160 mm 1 nos. 3. Insulated wire stripper 130 mm 1 nos. 4. Soldering Iron 25 Watt, 230 V 1 nos. 5. Neon Tester (0-500)V 1 nos. 6. Cathode Ray Oscilloscope 200 MHz, 2 Ch, 100

ksa/s As per requirement


1. Vero Board (100×160×1.6) mm 1 nos. 2. Diode (1N4007) 50V, 1 A 2 nos. 3. Resistance 1kΩ, 50V, ¼ watt 1 nos. 4. Step-down Transformer 230/12-0-12V, 500 mA 1 nos. 5. Soldering flux ISI mark As per requirement 6. Solderingwires Diameter (0.5-5) mm As per requirement 7. Connecting wires Single core, diameter


As per requirement


Schematic Diagram ofFull-Wave Rectifier:

Figure 10. Full-wave rectifier circuit along with input and output waveform

Theory: A rectifier is an electrical device that converts alternating current(AC), which periodically reverses direction, to direct current ( pulsating DC),which is only in one direction and the process is known as rectification. When only one diode is used to rectify AC(by blocking the negative or positive portion of the wave form),the difference between the term diode and rectifier merely one of usage, i.e. the term rectifier describes a diode that is being used to convert AC to DC. Almost all low power rectifiers comprise a number of diode in specific arrangement for more efficiently converting Ac to Dc than is possible with only one diode. A Full- wave rectifier converts the whole of the input waveform to one of constant polarity (positive or negative) at its output. Full-wave rectification converts both polarities of the input waveform to DC(direct current), and is more efficient. However, in circuit with non-center tapped transformer, four diodes are required instead of the one needed for half wave rectification. Four diodes arranged this way are called a diode bridge or bridge rectifier. For single phase AC, if the transformer is center-tapped, then two diodes back- to- back( i.e. anode-to-anode or cathode-to cathode) can form a full-wave rectifier which is shown in Fig.10. Twice as many windings are required on the transformer secondary to obtain the same output voltage compared to the bridge rectifier above.


The average and root- mean-square output voltage of an ideal single phase full wave rectifier can be calculated as:

𝐕𝐕𝐝𝐝𝐝𝐝 = 𝐕𝐕𝐩𝐩𝐚𝐚 =𝟐𝟐𝐕𝐕𝐩𝐩𝐩𝐩𝐩𝐩𝐩𝐩𝛑𝛑 , 𝐕𝐕𝐫𝐫𝐫𝐫𝐫𝐫 =

𝐕𝐕𝐩𝐩𝐩𝐩𝐩𝐩𝐩𝐩√2

Procedure:

1. Connect the diode to the low voltage AC power supply as shown in Fig.10. Note that the resistance used to limit the current.

2. Connect channel-1 (CH 1) of the oscilloscope to input and channel 2(CH 2) to output/load resistance of the circuit.

3. Switch on the oscilloscope and sinusoidal supply. 4. Sketch the input wave form. 5. Measure and record time T, peak voltage V

pand peak to peak voltage

Vpp

of the input supply. 6. With the DC coupled adjust the time-base and the Y-amplifier

sensitivity. 7. Sketch the wave form and label it to show the periods when the diode

D1 & D2 is conducting and those when it is not. Time T depends upon the frequency of your power supply.

8. Measure and record time T and peak voltage Vp of output wave form.

9. Confirm this Vpshould be very nearly equal to the peak voltage of the

alternating supply.

Observation: (Take Observation from Oscilloscope) Input: Sl.No Time (T) 𝐕𝐕𝐩𝐩 𝐕𝐕𝐩𝐩𝐩𝐩 𝐕𝐕𝐫𝐫𝐫𝐫𝐫𝐫

Output: Sl.No Time(T) V

p V

pp V

rms

Calculation: (Calculate the average dc voltage of designed circuit)


Conclusion: Precautions:

1. Do not touch the heating part of the soldering iron. 2. Always keep the soldering iron in its stand. 3. All joints should be provided with insulation grip.

Model Questions:

1. What is rectifier? 2. What is use of Resistor in Rectifier Circuit? 3. What is the use of a Rectifier Circuit? 4. What is full wave rectifier? How does it work?


ELECTRICAL, ELECTRONICS & COMPUTER SHOP NATIONAL INSTITUTE OF TECHNOLOGY

ROURKELA-769008

JOB-3

AIM: TO make an electrical wiring for controlling two lamps from a switch board.

Tools and Equipment Required: Sl. No. Name of the Tools Size Quantity

1. Insulated screw Driver 150 mm 1 nos. 2. Insulated Combination plier 160 mm 1 nos. 3. Insulated wire stripper 130 mm 1 nos. 4. Neon Tester (0-500)V 1 nos. 5. Pricker 150 mm 1 nos. 6. Hacksaw 160 mm (small) 1 nos.


1. Switch Single pole, 6A, 230V 2 nos. 2. 3 – pin plug 230 V, 6 A, ISI Mark 1 nos. 3. PVC Board 150x90 mm 1 nos. 4. PVC Board 100x100 mm 2 nos. 5. Batten holder 230 V, 6 A, ISI Mark 2 nos. 6. PVC insulation tape 0.125mm x 18mm 1 nos. 7. PVC insulated copper

wire 1.1 kV, 8 pair,1 mm sq.

As per requirement

8. PVC casing capping 16x25 mm As per requirement 9. Screws 20 mm & 12 mm 12 nos.


Schematic Diagram for controlling two lamps from a switch board

220 V

P N

PVC Pipe

PVC saddle clamp

Wooden Box

Wooden Box

Wooden Box

Single pole Switch

Figure 11.Electrical wiring for controlling two lamps from a switch board.

Procedure:

1. Mark the position of switches and holders on the board. 2. Cut the holes for housing switches and holders as per marking. 3. Fix the switches and holders on the board. 4. Make the wiring of switch board as per the wiring diagram shown in

Figure 11. 5. Make sure that all the connection as per the wiring diagram and are

tight. 6. Give power supply and test the switch board.


Conclusion: Precautions: 1. Tools should be used carefully. 2. Fitting should be tightly fitted. 3. Connection should be tight. 4. All the joints should be provided with insulation grip. Model Questions: 1. State the meaning of the term “OFF” and “ON”. 2. Write any two important precautions to be observed while fabricating

the switch board. 3. Why only ISI marked accessories are to be used in any electrical

installation? 4. State the importance of wiring diagram in connection to fabrication of

switch board. 5. How to identify the phase terminal in three pin socket with help of test

lamp? 6. State the meaning of ‘OPEN CIRCUIT’.


ELECTRICAL, ELECTRONICS & COMPUTER SHOP NATIONAL INSTITUTE OF TECHNOLOGY

ROURKELA-769008

JOB-4

Aim:To make the electrical connection of a fluorescent lamp Tools and Equipment Required: Sl. No. Name of the Tools Size Quantity



1. Tube light 20W, 230 V 1 nos. 2. Frame of tube light. 610 mm 2 nos. 3. Tumbler Switch Single pole, 6A, 230V 1 nos. 4. Ceiling rose 230 V, 6 A/(86×35) mm 1 nos. 5. 3 – pin plug 230 V, 6 A/ ISI Mark 1 nos. 6. PVC Board 150x90 mm 1 nos. 7. PVC Board 100x100 mm 1 nos. 8. PVC insulation tape 0.125x18 mm 1 nos. 9. PVC insulated copper

wire 1.1 kV, 8 pair,1 mm sq. As per requirement

10. PVC Casing capping 16x25 mm As per requirement 11. Screws 12 mm, 20 mm, 8 nos.


Theory: Fluorescentlamp is essentially a gas discharge tube. A voltage is applied between two electrodes of tube containing gas. Once the voltage exceeds the critical voltage, ionization voltage, gas is ionized and the ionized gas emits radiation, partly in visible range and partly in ultraviolet or infrared range. It is known that certain minerals absorb ultraviolet light and re-radiate in the visible region. One of the main sources of ultraviolet radiation is an electric discharge through mercury vapors at low pressure. Schematic Diagram of Fluorescent Lamp:

Ballast

Fluorescent Tube

Stater

Condensator

Bimetal switch

220 V

PN

Tungsten Filament

PVC PipePVC saddle clamp

Wooden Box

Wooden Box


Figure12. Schematic diagram of Fluorescent lamp

A Fluorescent lamp circuit has the basic parts such as the tube, choke, and starter which are shown in Fig.12. Due to low pressure the lamp is in the form of a long tube, the inside of which is coated with phosphor to convert ultraviolet light into visible light. Phosphor coating produce the required colour, for instance. For example, cadmium tungstate-Blue, zinc silicate-Green, Cadmium borate-Pink. The tube contains a small amount of mercury and argon gas at low pressure of 2.5mm of Hg. When the temperature increases, the mercury vaporizes and thus takes over the conduction of current. At each end of the tube, the electrodes are of spiral form made of tungsten and coated with an electron emitting material. The choke is connected in series with the tube filament which provides a voltage impulse for starting the lamp and acts as ballast during running. The electrodes are open the starter is cold. When connected to supply a full voltage is impressed on the starter. A glow discharge is set up in the starter which warms the electrode which causes the bimetal strip is to bend and touch the electrodes. The circuit gets closed and a current flows to the filament, thereby causing emission of free electrons. At the same time the voltage at starter falls to zero and the bimetal strips cool down. The starter electrodes are open and then interrupted the circuit current. Its effect is to induce high voltage surge of about 1000 volts in choke. This high voltage produces an arc between lamp electrodes and the lamp lights up immediately. Then starting switch contacts are left open. The current flow through the circuit is now only through the tube and choke. Resistance of the tube being less the current flow is through the high inductance choke resulting in a poor power factor (of order of 0.5).

Typical fluorescent tube is filled with inert gas and a small amount of mercury that creates vapor. Generating fluorescent light occurs in two stages. First, electrons emitted from cathodes create an electrical arc through mercury vapor. Then, resultant ultraviolet radiation strikes phosphor coating which then gives off visible light. Bi-pin bases are necessary for preheat and Rapid-Start fixture designs.


Procedure:

1. Collect all the parts of the fluorescent lamp as well as toll required for the electrical connection.

2. Connect all the parts through PVC wire and complete the circuit as given in the Fig.12

3. Give supply voltage and test. Conclusion: Precautions: 1. Tools should be used carefully. 2. Fitting should be tightly fitted. 3. Connection should be tight. Model Questions 1. What is standard diameter of tube light? 2. Which materials are used for coating the tube? 3. Which gas is used in tube light? 4. What are the standard lengths of the tube light? 5. What is the function of the starter? 6. Why we use choke in tube light? 7. How much power consumed by tube light? 8. Can you start the tube light without starter? 9. At which supply the tube light is connected? 10. Name any two type of starter?




JOB-5

Aim:To make electrical wiring for controlling different loads from a switch board.

Tools and Equipment Required: Sl. No. Name of the Tools Size Quantity



1. Switch Single pole, 6A, 230V 6 nos. 2. Lamp 40W, 230V 1 nos. 3. 3 – pin plug Top 230 V, 6 A 1 nos. 4. 5 pin plug socket 230 V, 6 A 2 nos. 5. Fuse 6A, 230V 1 nos. 6. Indicator 6A, 230V 1 nos. 7. Regulator 230 V, 80 w, 5 step 1 nos. 8. PVC switch board 250x200 mm 1 nos. 9. PVC insulation tape 0.125x18 mm As per requirement

10. PVC insulated copper wire

1.1 kV, 8 pair,1 mm sq. As per requirement


Schematic Diagram of a Switch Board

S S S

S

S S

FPFP

R

IF

P

I

N

Figure 13. Electrical wiring for controlling different loads from a switch board; P: Phase, N: Nutral, S: Single pole switch, I: Indicator, F: Fuse, G: Ground, FP: Five pin Plug, R: Regulator


Figure 14. Front view and rare view of Switch board

Figure 15. Different type of Electrical Load Procedure:


1. Mark the position of switches and socket on the switch board as shown in Fig.13.

2. Cut the holes on the switch board for housing switches and socket, as per marking.

3. Fix the switches and socket on the switch board. 4. Make the wiring of switch board as per the wiring diagram. 5. Also, connect proper earthing connection as per wiring diagram. 6. Make sure that all the connection as per the wiring diagram and are

tight. 7. Test the switch board with different electrical load.

Conclusion: Precautions:

1. Tools should be used carefully. 2. Fitting should be tightly fitted. 3. Connection should be tight. 4. All joints should be covered with insulation grip. 5. While making the connections plug should be disconnected from the

supply source.

Model Questions

1. How much voltage is applied in the single phase supply? 2. what is the bus bar? 3. Why we use regulator? 4. What is the maximum load on switch board? 5. What do you mean by colour of wiring? 6. What do you mean by PVC? 7. State the meaning of ‘SHORT CIRCUIT’.




JOB-6

Aim:To control a lamp from two positions and from multiple positions. Tools and Equipment Required: Sl. No. Name of the Tools Size Quantity


Materials required: Sl. No. Name of the Materials Rating/Size Quantity

1. Two-way Switch Single pole, 6A, 230V 10 nos. 2. Lamp 40W, 230V 1 nos. 3. 3 – pin plug Top 230 V, 6 A/ ISI Mark 1 nos. 4. PVC switch board 270 mm × 220 mm 1 nos. 5. PVC insulation tape 0.125x18 mm As per requirement 6. PVC insulated copper

wire 1.1 kV, 8 pair,1 mm sq. As per requirement

Procedure:

1. Mark the position of switches and socket on the switch board as shown in Fig.14 and Fig.15.

2. Cut the holes on the switch board for housing switches and socket, as per marking.

3. Fix the switches on the switch board. 4. Make the wiring of switch board as per the wiring diagram.


5. Make sure that all the connection as per the wiring diagram and are tight.

6. Test the switch board with different bulb load. 7. Similarly, for control a lamp from multiple positions repeat procedure

no. (2-6) as per diagram. Connection Diagram of a Lamp Control from Two Positions:

Off On

Figure16. Connection Diagram of a Lamp Control from Two Positions


Figure17. Wiring Connection Diagram of a Lamp Control from Two Positions


Connection Diagram of a Lamp Control from Multiple Positions:P

N Bulb

P

N

Figure 18. Connection Diagram of a Lamp Control from multiple Positions


Figure 19. Wiring Connection Diagram of a Lamp Control from multiple Positions

Precautions:

1. Tools should be handeled carefully. 2. Fitting should be tightly fitted. 3. Connection should be tight. 4. All joints should be covered with insulating tap. 5. While making the connections plug should be disconnected from

the supply source

Model Questions

1. How much voltage is applied in the single phase supply? 2. what is two-way switch? 3. How does a two-way switch work? 4. What is application of two-way switch connection? 5. What is the maximum load on switch board? 6. What do you mean by PVC?

manual electrical 1styr 09-25

Engineering