IM 12B6J3-02E-E 2nd edition

InstructionManual

Model FU20pH/ORP Combination sensor

TABLE OF CONTENTS

1. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-2. Unpacking and Checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-3. Warranty and Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

2. General Specifications FU20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22-1. Measuring elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22-2. Construction materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22-3. Functional specifications (at 25°C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22-4. Dynamic specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22-5. Operating range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

3. Installation Site FU20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33-1. Typical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33-2. Preparing the Sensor for Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33-3. Mounting the Sensor into the Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

4. Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74-1. Conventional pH (& ORP) Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74-2. Wiring for ORP measurement with normal reference . . . . . . . . . . . . . . . . . . . . . . . . .74-3. Wiring for ORP measurement with pH reference . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

5. General Calibration & Maintenance Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . .85-1. Calibration for pH measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85-2. Calibration for ORP measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85-3. Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

6. Model Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

7. Spare Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

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1. GENERAL

1-1. IntroductionThis instruction manual providesinformation for the installation and use ofthe FU20, four-in-one wide body pHsensors. The FU20 is the choice for themajority of typical wastewater and processapplications.

The Model FU20 offers a simple and costeffective solution for a wide variety ofwastewater and process applications. Thisall-in-one sensor provides simultaneousmeasurement of pH, redox (ORP) andtemperature if desired. The rugged Rytonbody is designed for easy installation intoon-line and immersion applications via the3/4" NPT threaded connections providedon both ends of the sensor. Optionalquick-removal adapters in both stainlesssteel and titanium are available to makecalibration and maintenance even easier.

The FU20 include an integral cable ofoptional lengths designed to minimize theadverse affects of noise can have on themeasurement. This cable is pre-finished tomake connection to any industrial pHinstrument as simple as possible. TheFU20 can also include a multiple VPconnector and then requires seperatecable type WU10-V-S that somes invariable lengths.

1-2. Unpacking and CheckingUpon delivery, unpack the sensor carefullyand inspect it to ensure it was notdamaged during shipment. If damage isfound, retain the original packing materials(including outer box) and then immediatelynotify the carrier and the relevantYokogawa sales office. Make sure theModel Code on the sensor is the same ason the packing list. Also, check anyoption(s) that were ordered are includedand correct. The sensor has anidentification number on the cable with thefull Model Code and a Serial Numberincluded.

1-3. Warranty and ServiceYokogawa products and parts areguaranteed free from defects inworkmanship and material under normaluse and service for a period of (typically) 12months from the date of shipment from themanufacturer. Individual sales organizationscan deviate from the typical warrantyperiod, and the conditions of sale relatingto the original purchase order should beconsulted. Damage caused by wear andtear, inadequate maintenance, corrosion,or by the effects of chemical processes areexcluded from this warranty coverage. Inthe event of warranty claim, the defectivegoods should be sent (freight paid) to theService Department of the relevant salesOrganization for repair or replacement (atYokogawa’s discretion).

The following information must be includedin the letter accompanying the returnedgoods:

1. Model Code and Serial Number.2. Original Purchase Order and Date.3. Length of time in service and description

of the process.4. Description of the fault and

circumstances of the failure.5. Process/environmental conditions that

may be related to the failure of the sensor6. Statement as to whether warranty or

non-warranty service is requested.7. Complete shipping and billing

instructions for return of material, plusthe name and phone number of acontact person that can be reached forfurther information.

Returned goods that have been in contactwith process fluids must bedecontaminated and disinfected prior toshipment. Goods should carry a certificateto this effect, for the health and safety ofour employees. Material Safety Data sheetsmust be included for all components of theprocess to which the sensors/fittings havebeen exposed.

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2. GENERAL SPECIFICATIONS FU20

2-1. Measuring elements : pH glass electrode: Silver chloride reference: Solid platinum electrode: Pt1000 temperature sensor.

2-2. Construction materialsBody : PPS 40GF (Ryton) with glass fillingEarthing pin : Solid PlatinumO-ring : VitonReference junction : Porous PTFECable : Coaxial with 4 extra leads

2-3. Functional specifications (at 25°C)Isothermal point : pH 7Glass impedance

- Dome shape : 250 to 500 MΩ- Flat Surface : 400 to 1000 MΩ

Reference system : Ag/AgCl with saturated KCIJunction resistance : 0.5 to 5 kΩTemperature element : Pt1000 to IEC 751Asymmetry potential : < 15 mVSlope : > 96 % (of theoretical value)

NOTE: The temperature sensor included in the FU20 is intended to provide indication andcell compensation. The construction has not been tested to the pressure vesselstandards required for plant temperature control.

2-4. Dynamic specificationsResponse time pH step (7 to 4) : < 15 sec for 90%Response time temp step (10°C)

- Dome shape : < 3 min for 90%- Flat Surface : < 6 min for 90%

Stabilisation time (0.02 pH unit/ 10 s) : < 2 minutes

2-5. Operating rangepH : 0 to 14Temperature : -10 to 105 °C (14 to 221 °F)Pressure : 0 to 10 bar ( 0 to 145 PSIG)Conductivity : > 50 µS/cmStorage temperature : -30 to 50 °C (-22 to 122 °F)

NOTE: Specifications should not be considered in isolation. For example the pH range canbe 2-12 pH, where the measurement is at elevated temperatures. For advice aboutspecific applications please contact you local sales office.

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3. INSTALLATION OF FU20

For optimum measurement results, theFU20 should be installed in a location thatoffers an acceptable representation of theprocess composition and DOES NOTexceed the specifications of the sensor.The FU20 is designed with threads oneither end of the body 3/4" NPT to allowinstallation in a wide variety of applications.

3-1. Typical InstallationThe FU20 sensor is designed for in-lineinstallation, via a bypass loop as animmersion assembly. For best results theFU20 should be mounted with the processcoming towards the sensor (Fig 7) andpositioned at least 15° above the horizontalplane to eliminate air bubbles in the glassbulb.

3-2. Preparing the Sensor for UseRemove the sensor from its shipping boxand slide off the "wet pocket" (the tubefilled with solution to keep the measuringelements from drying out in storage orshipment).

IMPORTANT NOTICEBefore mounting the sensor, it should becalibrated. The calibration procedure isnormally described in the InstructionManual of the pH transmitter, but a generalcalibration is given in section 7 of thismanual.

3.3 Mounting the SensorThe FU20 can be mounted using thethreads on the body of the sensor (Fig. 6).Apply Teflon tape to the appropriatethreaded end, then install in the process.

The FU20 can also be mounted using thethreaded end of the quick release adapter.Apply Teflon (PTFE) tape to the threadedend of the quick release adapter (step 2).Then install the adapter (/NSS, /NTI, /BSPor /BTI) in the process, tightening it byapplying a suitable torque using a spanneron the adapter flats, steps 1 & 3.

Next, slide the mating part of the adapterfrom the cable end of the FU20 (step 4)sensor and mount into the adapter makingsure that the O-ring seats properly (step 5 &6). Hand tightened the adapter nut (step 7).

NOTE:DO NOT over tighten the sensor, as damage may result.

See Section 6 for instructions to wire thesensor to the instrument.

FU20

TeflonTape

FU20

Figure 6. Sensor Installation

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Wrench Flats

Teflon Tape

Process Flow

Do NOTovertighten

Figure 7. Sensor & adapter Installation

Teflon Tape

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FU20

O-ring

Fitting

Adapter( /FPS )

O-ring

/HCNF, SPRAY CLEANER

FU20 + ADAPTERFU20 + FD40

Figure 8. Installation examples for the FU20

ProcessFlow

/SN3/SR3/FN4/FR4

CleaningSolution

(water, acid, etc.)

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3/4" TAPERED THREAD 3/4" TAPERED THREAD

22.5 (0.89")

19.7 (0.78")19.7(0.78")

Ø26

.0(1

.02"

)

1” NPT or ISO 7/1-R1

51.0 (2.3")

150.0 (5.9")

10.0 (0.39")

Ø22

.0(0

.86)

Ø 35.5 (1.4")

Ø 39.0 (1.54")

99.0

(3.9

")

25.0

(1")

1” NPT orISO 7/1-R1

Ø 30.0 (1.18")

Ø 30.0 (1.18")

Ø 36.0 (1.42")

10.0

(0.4

")

5.0

(0.2

")

35.0

(1.3

8")

Figure 9. Dimensions FU20

Figure 10. Dimensions 1” FU20 adapter Stainless Steel & Titanium

Figure 11. Dimensions FU20 adapter for FF40, FS40 and FD40 fittings

-NPT

/NSS, /NTI, /BSP, /BTI

-FSM

/NSS, /NTI, /BSP, /BTI

/FPS

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FU

20-V

P-

FU

20-V

P-

FU

20-V

P-

(pH)A

(Ref.)B

C(ORP/LE)

D

(Temp)E

(Temp)F

(pH)A

Core coax (15)

(Temp)E

Blue (12)

(Temp)F

Red (11)

(ORP/LE)D

Black

(Ref.)B

Shield coax (13)

C

FU2

0-V

P-

ø6.5

A(pH)

B(Ref.)

CD

(ORP liquid Earth)

E (Temp)

F (Temp)

VP-connector

4.1. Cable marking and pin allocation.fixed cable WU10 cable

Signal description color number VP connector colorpH Glass Clear 15 A ClearShield of pH black 16 -REF black 13 B Brown- - C -ORP/Liquid Earth Yellow 14 D BlackTEMP Red 11 E RedTEMP(2) Blue 12 F BlueShield - Yellow

4.2. Termination of sensor as function of measurementFunction pH pH&ORP pH&rH ORP pH compen-

Signal descr. sated ORPpH Glass 15 15 15 - 13Shield of pH 16 16 16 - 17REF 13 13 13 13 --ORP/Liquid Earth 14 14 14 15 15TEMP 11 11 11 11 11TEMP(2) 12 12 12 12 12Shield 63 63 63 63 63Jumper - - - 13-14 14-15

The settings for the pH converters must be set according to the instructions in theInstruction Manual of the converter. In the following table these settings are summarized.

4. WIRING

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5-1. Calibration for pH measurementTo calibrate a pH sensor, two buffersolutions with known pH values arerequired. It is recommended that one buffersolution have a value near to pH 7.00.Depending on the process value to bemeasured, the second buffer solutionshould be either acidic (below 7.00) oralkaline (above 7.00) area. Normally, the IECbuffers (4.01, 6.87 and 9.18) are used.

The following is a very general 2-point calibration procedure.1. Clean the sensor (deposits may be

removed using a 5% (approximate) solution of HCL).

2. Rinse sensor thoroughly with cleanwater.

3. Immerse the sensor in the first buffer(6.87 pH is recommended).

4. Refer to appropriate InstrumentInstruction Manual for Calibration procedures (Auto; Manual; Sample, etc.),

5. Rinse sensor thoroughly with clean water.

6. Immerse the sensor in the second buffer(4.01 or 9.18 recommended).

7. Repeat Step 4.

During calibration the temperature compensation should be active. The instrument automatically compensates forthe sensitivity change of the pH sensor atdifferent temperatures. After calibration iscomplete replace or re-install the sensorinto the process.

5-2. Calibration of ORP and rH measurements

For calibration of ORP and rH theprocedures for MANUAL CALIBRATION can be used as described in the instructionmanual of the analyser. The mostly usedstandards for ORP and rH calibration aremade from Chinhydron ( Quinhydrone)powder dissolved in pH buffer solutions. (1 gram/200 ml) The ORP value is a functionof the Reference cell of the measurementand the pH value of the buffer solution.

4.2.1. Settings for PH402G and PH202G(S)Function pH

pH&ORP pH&rH ORPpH compensated

Setting (default) ORPcode 01 0(pH) 0(pH) 0(pH) 1(ORP) 1(ORP)code 02 0(off) 1(ORP) 2(rH) 0(off) 0(off)code 03 1.1.1 1.1.1 1.1.1 0.0.1 0.0.1code 04 0.0.1 0.0.1 0.0.1 0.0.1 1.1.1code 31 0 2 2jumper input 1 no no no yes yesjumper input 2 yes yes yes yes no

4.2.2. Settings for PH150 and PH450GFunction pH

pH&ORP pH&rH ORPpH compensated

Setting (default) ORPsensor setup pH pH+ORP pH+ORP ORP ORPmeasurement setup

pH+ORP pH+rH

Impedance settinginput1 High High High Low Lowinput 2 Low Low Low Low Highjumper input 1 no no no yes yesjumper input 2 yes yes yes yes no

5. GENERAL CALIBRATION & MAINTENANCE PROCEDURE

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Model Suffix Option DescriptionCode codeFU20 Wide body sensorCable length -03 3 mtr

-05 5 mtr-10 10 mtr-20 20 mtr-VP Vario Pinconnector (no cable)

Temp. element -T1 Pt1000Model -NPT Dome shape model

-FSM Flat surface modelOptions /HCNF Hastelloy cleaning system

/FPS Adapter F*40 from noryl/NSS 1” NPT adapter, SS (316L)/NTI 1” NPT adapter, Titanium/BSP 1” BSP adapter, SS (316L)/BTI 1” BSP adapter, Titanium

6. MODEL CODES

The FU20 has a reference system ofSaturated Silver/Silver Chloride and thevalues are given in the following table asfunction of the measurement function ( 4.2)

Function ORP pH comp. ORP rHpH= 1,68 403 88 23,6pH= 4,01 265 88 23,6pH= 6,87 96 88 23,6pH= 7,00 88 88 23,6

The accuracy of the standard values isapproximately +/- 10 mV.

5-3. MaintenanceAll pH sensors require routine maintenanceto keep the measuring elements clean andfunctioning. Depending on the process,different cleaning solutions may be required.

EXAMPLES:1. Deposits of limes, hydroxides or

carbonates can be removed by immersingthe sensor in a solution containing dilutehydrochloric acid (5% is recommended).Afterwards rinse with water.

2. Deposits of oil and fat can be removedwith hot water in conjunction with adetergent. When the results are unsatisfactory, a mild (carbonate based)abrasive can be used.

3. Protein deposits should be removed witha protein enzymatic solution. For instancea solution containing 8.5ml concentratedhydrochloric acid and 10 grams of pepsin in 1 liter of water will do.

After cleaning the probe is reinserted into theprocess by following the reverse procedure.

NOTE:Avoid using non-polar solvent like tri-chloroethylene, toluene or hexane. Cleaning withiso-propanol or methanol is acceptable.

The non-polar solvents will break up thegel-layer on the glass bulb and requires thatthe electrode to be soaked in waterfor at least 12 hours before functioning normally again. The Teflon (PTFE)diaphragm of the sensor can sometimes be regenerated by putting it in hot (60 to 80°C)3 molar Potassium Chlorine (KCL) solutionand letting it cool to room temperature.This procedure clears the junction of process material and then "draws" the conductive (KCL) back into the junction.

IM 12B6J3-02E-E Printed in The Netherlands, 02-606 (A) QSubject to change without noticeCopyright ©

YOKOGAWA

YOKOGAWA EUROPE B.V.Databankweg 203821 AL AMERSFOORTThe NetherlandsTel. +31-33-4641 611Fax +31-33-4641 610www.yokogawa.com/eu

YOKOGAWA CORPORATION OF AMERICA2 Dart RoadNewnan GA 30265United StatesTel. (1)-770-253-7000Fax (1)-770-251-2088www.yokogawa.com/us

YOKOGAWA ELECTRIC ASIA Pte. Ltd.5 Bedok South RoadSingapore 469270SingaporeTel. (65)-241-9933Fax (65)-241-2606www.yokogawa.com.sg

YOKOGAWA HEADQUARTERS9-32, Nakacho 2-chome,MusashinoshiTokyo 180JapanTel. (81)-422-52-5535Fax (81)-422-55-1202www.yokogawa.com

Yokogawa has an extensive sales and distribution network. Please refer to the European website (www.yokogawa.com/eu) to contact your nearest representative.

7. SPARE PARTS

Spare part Description

FU20K1523DD /FPS Adapter for FF40, FS40 and FD40 fittings (PPO)K1547PK /NSS 1” NPT, Stainless Steel adapter (Viton O-ring)K1547PL /BSS ISO 7/1-R1, Stainless Steel adapter (Viton O-ring)K1547PM /NTI 1” NPT, Titanium adapter (Viton O-ring)K1547PN /BTI ISO 7/1-R1, Titanium adapter (Viton O-ring)K1500 FR Viton O-rings 29.82*2.62 (5 pcs) for 1” adapterK1500FS EPDM O-rings 29.82*2.62 (5 pcs) for 1” adapterK1500FT Silicone O-rings 29.82*2.62 (5 pcs) for 1” adapter

Cleaning system for FU20K1547PJ Hastelloy cleaning system (HCNF) K1547PG Hastelloy nozzle and mounting set (HCNF) K1547PH Nylon tube (10 metre) and tube mounting set for chemical

cleaning system

Buffer powder6C231 Buffer powder pH 1.68 ; IEC746-26C232 Buffer powder pH 4.01 ; IEC746-26C236 Buffer powder pH 9.18 ; IEC746-26C237 Buffer powder pH 6.87 ; IEC746-2

Connection equipmentBA10 Junction box for pH extension cablesWF10-XXX-F pH signal cable with terminated ends. Specify length in whole

meters (e.g. XXX = 020)WU10-V-S Variopin cable