YOKOGAWA PH8EHP User manual

User’s
Manual
Model PH8EHP
pH Sensor for High Purity Water
IM 12B7J2-01E
IM 12B7J2-01E
11th Edition

IM 12B7J2-01E
< Introduction > i
INTRODUCTION
This manual covers the PH8EHP pH Sensor for High Purity Water.
Other related items are described in the following manuals.
Model Title IM No.
PH8HH pH Holder for High Purity Water IM 12B07P01-01E
PH8AX Accessories for pH Meter IM 12B07W03-01E
PH400G Four-wire Type pH Converter IM 12B7C1-02E
PH450G Four-wire Type pH Converter IM 12B07C05-01E
FLXA402 4-Wire Converter IM 12A01F01-02EN
IM 12A01F02-01EN etc.
PH202G, S Two-wire Type pH Transmitter IM 12B07D02-01E
PH202SJ TIIS Intrinsic safe pH/ORP Transmitter IM 12B07D02-11E
FLXA202, FLXA21 Two-wire Liquid Analyzer IM 12A01A02-01E
WTB10-PH¨Terminal Box IM 19D01B01-01E
PH8TBG Terminal Box IM 12B07W01-01E
Media No. IM 12B7J2-01E 11th Edition : Nov. 2018 (YK)
All Rights Reserved Copyright © 1983, Yokogawa Electric Corporation
11th Edition : Nov.20,2018-00

IM 12B7J2-01E
< Introduction > ii
For the safe use of this equipment
n Safety,Protection,andModicationoftheProduct
• In order to protect the system controlled by the product and the product itself and ensure
safe operation, observe the safety precautions described in this user’s manual. We assume
no liability for safety if users fail to observe these instructions when operating the product.
• If this instrument is used in a manner not specified in this user’s manual, the protection
provided by this instrument may be impaired.
• Be sure to use the spare parts approved by Yokogawa Electric Corporation (hereafter simply
referred to as YOKOGAWA) when replacing parts or consumables.
• Modicationoftheproductisstrictlyprohibited.
• The following symbols are used in the product and user’s manual to indicate that there are
precautions for safety:
nNotes on Handling User’s Manuals
• Please hand over the user’s manuals to your end users so that they can keep the user’s
manuals on hand for convenient reference.
• Please read the information thoroughly before using the product.
• The purpose of these user’s manuals is not to warrant that the product is well suited to any
particular purpose but rather to describe the functional details of the product.
• No part of the user’s manuals may be transferred or reproduced without prior written
consent from YOKOGAWA.
• YOKOGAWA reserves the right to make improvements in the user’s manuals and product at
any time, without notice or obligation.
• Ifyouhaveanyquestions,oryoundmistakesoromissionsintheuser’smanuals,please
contact our sales representative or your local distributor.
nWarning and Disclaimer
The product is provided on an “as is” basis. YOKOGAWA shall have neither liability nor
responsibility to any person or entity with respect to any direct or indirect loss or damage arising
from using the product or any defect of the product that YOKOGAWA can not predict in advance.
nCompliance with the simple apparatus requirements
PH8EHPmeetthesimpleapparatusrequirementsdenedinthefollowingstandards.
Note: TIIScertiedtypescannotbeconnected.
Use the sensors under the conditions of use required by the standards.
Applicable standards:
ANSI/ISA-60079-11 (2014)
ANSI/ISA-60079-0 (2009)
CAN/CSA-C22.2 NO. 60079-11:14
CAN/CSA-C22.2 NO. 60079-0:11
방호장치 의무안전인증 고시
GB 3836.4-2010
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IM 12B7J2-01E
< Introduction > iii
Conditions of use:
(1) Use in combination with an internally isolated transmitter, or use with, a transmitter in
combination with isolated barrier.
The FLXA21 is internally isolated.
(2) Upper limit of the process temperature.
The upper limit of process temperature is indicated below when the sensor is used in
combination with a YOKOGAWA transmitter.
ForFLXA21,modelandsu󰀩xcodebelowisavailable.
FLXA21-D-□-D-EA-P1-○-A-N-LA-N-NN
 □canbeanyvalue.
 ○mustbeNNorP1.
Any option code is available.
ForPH202S,modelandsu󰀩xcodebelowisavailable.
 PH202S-○-E
 ○mustbeCorU.
There are no PH202S models that meet the Korean explosion proof standards.
Any option code is available.
Upper limit of process temperature on the PH8EHP
Transmitter used in combination FLXA21 PH202S
Ambient temperature Ta
Temperature class 40°C 60°C 40°C 60°C
T6 16 16 28 28
T5 50 31 50 43
T4 50 50 50 50
T3 50 50 50 50
T2 50 50 50 50
T1 50 50 50 50
Other warnings are provided in the following.
WARNING
Handling precautions:
(1) Potential electrostatic charging hazard Electrostatic charge may cause an explosion hazard.
Avoid any actions that cause the generation of electrostatic charge, e.g., rubbing with a dry
cloth.
(2) Because the solution ground tip contains titanium, ignition sources due to impact and friction
sparks are excluded.
(3) IEC60079-14 (Electrical installations in hazardous areas) requires a label indicating ‘simple
apparatus’, stick this label to this sensor if necessary.
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IM 12B7J2-01E
< Introduction > iv
nSymbol Marks
Throughoutthisuser’smanual,youwillndseveraldi󰀨erenttypesofsymbolsareusedtoidentify
di󰀨erentsectionsoftext.Thissectiondescribestheseicons.
WARNING
Indicates a potentially hazardous situation which, if not avoided, could result in death or serious
injury.
CAUTION
Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate
injury. It may also be used to alert against unsafe practices.
IMPORTANT
Indicates that operating the hardware or software in this manner may damage it or lead to system
failure.
NOTE
Draws attention to information essential for understanding the operation and features.
Tip
This symbol gives information that complements the current topic.
SEE ALSO
Thissymbolidentiesasourcetobereferredto.
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IM 12B7J2-01E
< Introduction > v
After-sales Warranty
nDo not modify the product.
nDuring the warranty period, for repair under warranty consult the local sales
representativeorserviceo󰀩ce.Yokogawawillreplaceorrepairanydamaged
parts. Before consulting for repair under warranty, provide us with the model
name and serial number and a description of the problem. Any diagrams or
data explaining the problem would also be appreciated.
lIf we replace the product with a new one, we won’t provide you with a repair report.
lYokogawa warrants the product for the period stated in the pre-purchase quotation
Yokogawashallconductdenedwarrantyservicebasedonitsstandard.Whenthe
customer site is located outside of the service area, a fee for dispatching the maintenance
engineer will be charged to the customer.
nIn the following cases, customer will be charged repair fee regardless of
warranty period.
• Failure of components which are out of scope of warranty stated in instruction manual.
• Failure caused by usage of software, hardware or auxiliary equipment, which Yokogawa
Electric did not supply.
• Failureduetoimproperorinsu󰀩cientmaintenancebyuser.
• Failureduetomodication,misuseoroutside-of-specicationsoperationwhichYokogawa
does not authorize.
• Failureduetopowersupply(voltage,frequency)beingoutsidespecicationsorabnormal.
• Failure caused by any usage out of scope of recommended usage.
• Anydamagefromre,earthquake,stormsandoods,lightning,disturbances,riots,warfare,
radiation and other natural changes.
n Yokogawadoesnotwarrantconformancewiththespecicapplicationatthe
usersite.Yokogawawillnotbeardirect/indirectresponsibilityfordamagedue
toaspecicapplication.
n YokogawaElectricwillnotbearresponsibilitywhentheuserconguresthe
product into systems or resells the product.
n Maintenanceserviceandsupplyingrepairpartswillbecoveredforveyears
after the production ends. For repair for this product, please contact the
nearestsaleso󰀩cedescribedinthisinstructionmanual.
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vii
IM 12B7J2-01E
<CONTENTS>
11th Edition : Nov.20,2018-00
Model PH8EHP
pH Sensor for High Purity Water
CONTENTS
IM 12B7J2-01E 11th Edition
INTRODUCTION.............................................................................................i
For the safe use of this equipment.............................................................ii
After-sales Warranty ....................................................................................v
1. Specication ............................................................................................. 1-1
1.1 StandardSpecications................................................................................... 1-1
1.2 ModelandSu󰀩xcodes.................................................................................... 1-2
1.3 External Dimensions ........................................................................................ 1-4
2. Installation................................................................................................. 2-1
2.1 Preparation for Installation .............................................................................. 2-1
2.1.1 Unpacking and Inspection ................................................................. 2-1
2.1.2 Mounting Glass Electrode.................................................................. 2-2
2.1.3 Mounting Liquid Junction ................................................................... 2-2
2.1.4 Installing Holder ................................................................................. 2-2
2.1.5 Installing Associated Instruments ...................................................... 2-2
2.2 pH Sensor Cable Wiring Procedure................................................................ 2-3
2.2.1 Connecting Sensor Cable.................................................................. 2-3
2.2.2 Installing the sensor ........................................................................... 2-4
3. Maintenance on operation....................................................................... 3-1
3.1 Names of Component....................................................................................... 3-1
3.2 Operation and Periodic Maintenance ............................................................. 3-2
3.2.1 CalibratingpHSensorUsingBu󰀨erSolutions................................... 3-2
3.2.2 Replenishment of KCl Solution.......................................................... 3-2
3.2.3 Cleaning Glass Electrode and Liquid Junction.................................. 3-2
3.3 Replacing Consumable Parts.......................................................................... 3-2
3.3.1 Replacing Glass Electrode ................................................................ 3-2
3.3.2 Replacing Liquid Junction.................................................................. 3-2
3.3.3 Replacing O-rings for Glass Electrode .............................................. 3-3
Customer Maintenance Parts List...................................... CMPL 12B05J02-01E
Revision Information ...............................................................................................i

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  <1.Specication> 1-1
IM 12B7J2-01E
1. Specication
TheModelPH8EHPpHSensorisusedtocongureapurewaterpHtransmissionsystem.Whenthis
sensor is used in a PH8HH pure water holder, it is possible to measure a low conductive solution at
lowowrateaccurately.
1.1 StandardSpecications
Measurement principle: Glass electrode method
Measuring range: 0 to 14 pH
Installation: Mounting in PH8HH holder
Temperature compensation sensor : Pt1000
Wetted part materials:
Body; Ryton (PPS resin), glass, titanium, ceramics, Fluoro rubber (FKM)
Cable; Chlorinated polyethylene rubber (Cable sheath)
KCl solution supply tube: Heat-resistant soft PVC
Cable length: 3, 5, 7, 10, 15 or 20 m
Operating conditions:
Solution temperature: 0 to 50°C
Solution pressure: Under atmospheric pressure
Solutionowrate: 30to600mL/min
Note:Themaximumowrateisrestrictedbythemeasuredsolutionconductivity.
 Solutionconductivity: 0.1μS/cmormore(seefollowinggure)
600
500
400
300
200
100
00.1 0.2 0.3 0.4 0.5 0.6 50
Optimum range
(mL/min)
Conductivity of Measured Solution (μS/cm)
Flow Rate of Measured Solution
F1.0.ai
KCl solution consumption: Maximum 3 mL/day (10 kPa pressurized)
Weight:
Sensor; Approx. 0.4 kg (Body)
KCl Tank; Approx. 0.3 kg (General purpose)
Approx. 0.8 kg (Big volume)
Characteristics :
Output Response: Response time (for 90% response): 10 seconds maximum
(when the sensor, stabilized at 20°C, measures a solution at 20°C).
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  <1.Specication> 1-2
IM 12B7J2-01E
1.2 ModelandSu󰀩xcodes
lpH Sensor
Model Su󰀩xCode Option Code Description
PH8EHP .............................................. ..................... pH sensor for high purity water
Cable Length -03
-05
-07
-10
-15
-20
.....................
.....................
.....................
.....................
.....................
.....................
3 m
5 m
7 m
10 m
15 m
20 m
Solution Ground Tip -TN ..................... Titanium
KCl Reserve Tank
(*1)
-TT1
-TT3
-TN1
.....................
.....................
.....................
For general purpose (250 mL solution inlet)
Big volume tank (With 500 mL tank)
For maintenance (for TT1)
- -N ..................... Always -N
Measuring System -H
-E
-F
-G
.....................
.....................
.....................
.....................
For PH200/PH400 (*2)
For PH202/FLXA202/FLXA21 (*3)
For FLXA202/FLXA21 (*5)
For FLXA402, PH450G, PH202/TB (*4)
Style *A ..................... Style A
*1: Only a KCl supply tube is supplied with TN1. KCl solution is supplied with TT1 and TT3.
*2: Mark band is shown by alphanumeric and fork terminals are used.
*3: Mark band is shown by numeral and pin terminals are used. When terminal box is used, select WTB10-PH1.
*4: Mark band is shown by numeral and M3 ring terminals are used. When terminal box is used, select WTB10-PH3.
*5: Mark band is shown by numeral and M4 ring terminals are used. When terminal box is used, select WTB10-PH5.
lAccessories
Model Su󰀩xCode Option Code Description
PH8AX .................... ..................... Accessories for pH meter (*1)
Calibration
Reagents
-L
-P
.....................
.....................
Two bottles, each containing 250 mL solution (pH7 and pH4)
24 bags, each bag containing powder for 500 mL solution (pH7 X
12 bags and pH4 X 12 bags) and two 500 mL polyethylene bottles.
Style *A ..................... Style A
Option /STD
/KCLL
/KCLP
/TMP
Sensor stand (with mounting bracket for 50A 2-inch pipe)
KCl solution (one 250 mL polyethylene bottle)
KCl powder (three bags, 250 mL solution each)
Thermometer (0 to 100 °C)
*1: Including the following:
Two 200 mL polyethylene cups
One cleaning bottle
*2: Either /KCLL or /KCLP is required for PH8EFP-□-□-TT2.
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  <1.Specication> 1-3
IM 12B7J2-01E
lConsumables
Part Name Part
Number Remarks
Glass electrode K9142TN One
Junction K9142TK One
KCl solution (3.3 mol/L) K9084LP Six 250 mL polyethylene bottles
Bu󰀨ersolutionforcalibration(pH4) K9084LL Six 250 mL polyethylene bottles
Bu󰀨ersolutionforcalibration(pH7) K9084LM Six 250 mL polyethylene bottles
Bu󰀨ersolutionforcalibration(pH9) K9084LN Six 250 mL polyethylene bottles
Powderforbu󰀨ersolution(pH4) K9020XA 12 bags, each for preparation of 500 mL
Powderforbu󰀨ersolution(pH7) K9020XB 12 bags, each for preparation of 500 mL
Powderforbu󰀨ersolution(pH9) K9020XC 12 bags, each for preparation of 500 mL
KCl powder (for PH8EHP) K9020XU 8 bags, each for preparation of 250 mL
Note: ThepHvalueofthecalibratingbu󰀨ersolutionmayvarydependingonstorageconditions.
Prepare a new solution from powder for accurate instrument calibration
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  <1.Specication> 1-4
IM 12B7J2-01E
1.3 External Dimensions
Cable
length: L Tube
length: L
64
115
Ø27.5
Ø38
GE S RE SE T1 T2
("-H": Fork terminal)
15 16 13 14 11 12
("-E": Pin terminal)
F1.1.ai
Unit: mm
15 16 13 14 11 12
Cable gland is not included.
Reuse existing gland, or replace.
Terminal No. and colors
GE
RE
T1
T2
SE
S
15 (Red)
13 (Brown)
11 (Black)
12 (White)
14 (Green)
16 (Yellow)
("-G", "-F": Ring terminal)
General purpose KCl reserve tank
(with mounting bracket)
(PH8EHP-)-TT1
2-inch pipe
Ø63
Approx.115
Approx.75 Approx.45
Approx.105
Approx.151
60
25
Ø105
60
2-inch pipe
(Ø60.5)
2-Ø9(M8 screw) holes
Big volume tank KCl reserve tank
(with mounting bracket)
(PH8EHP-)-TT3
70±0.2
Hole requirements
for wall mounting
Figure 1.1 PH8EHP pH Sensor
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< 2. Installation > 2-1
IM 12B7J2-01E
2. Installation
2.1 Preparation for Installation
2.1.1 Unpacking and Inspection
The Model PH8EHP pH sensor is well packed so as to prevent damage during shipment.
After removing the sensor from its shipping container, visually check the sensor for damage.
NOTE
(1) When delivered, the "glass electrode" and the "liquid junction" are packed separate from the
sensor body.
(2) So that caps of the “glass electrode” and the “liquid junction” do not dry out, do not take unpack
these at this time.
Made in Japan
No.
PH8EHP -
MODEL
F2.1.ai
03-TN-TT1-N-H*A
Figure 2.1 An Example of Model Number Entering to Nameplate
F2.2.ai
Glass Electrode
Liquid Junction
Solution Ground Tip
Sensor Body
Figure 2.2 Names of PH8EHP pH Sensor Components
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< 2. Installation > 2-2
IM 12B7J2-01E
2.1.2 Mounting Glass Electrode
Mount the glass electrode on the sensor body as per the following procedure:
(1) Peelo󰀨thesealfromtheelectrodemountingholeonthesensorbody.
(2) Removethecapfortheglassmembrane.Wipeo󰀨anysolutionremainingontheO-ringwitha
tissue or other material.
(3) Remove the cap for the gold-plated pin.
(4) ConrmthatthereisnodamageontheO-ringthatmighta󰀨ectitssealingperformance.
(5) Mount the glass electrode on the sensor body. Insert the electrode in the mounting hole and
screwitclockwiseuntiltheO-ringtstightlyinthehole.
NOTE
•AsshowninFigure(a),thecapfortheglassmembranecontainsthesolutiontokeepwet(pH4bu󰀨er
solution). Do not splash the solution when removing the cap. Remove the cap carefully because the
rod beside the glass membrane is very fragile.
• Before mounting the glass electrode on the sensor body, make sure that the O-ring and the gold-
platedpinarenotwet.Wipeo󰀨anyremainingsolution.
•Makesurethattherearenodropletsinthemountinghole.Wipeo󰀨anydroplets,ortheymaycause
insulation failure.
• Use the electrode within one year after purchase. The solution to keep wet gradually evaporates
over time. A glass electrode whose glass membrane has dried out does not provide stable readings
until it gets used to the solution. As shown in Figure (b), place in advance the glass electrode either
inthepH4orpH7bu󰀨ersolutionformorethanadaybeforeusing.
Make sure the part above the O-ring is not wetted.
Case part No.: K9008WT
Cap for the gold-plated pin
Cap for the glass membrane
Solution to keep wet (inside)
(a) (b)
2.1.3 Mounting Liquid Junction
The liquid junction is mounted in the sensor body when the KCl solution is poured into the sensor
body. Refer to Section 2.2.
2.1.4 Installing Holder
Usually,thepHsensorissuspendedinaguidepipeorinstalledinaow-throughorsubmersible
holder. First install the holder.
2.1.5 Installing Associated Instruments
Make sure that the associated instrument (a pH transmitter/converter or a junction terminal box) to
which the pH sensor cable is connected has already been installed.
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< 2. Installation > 2-3
IM 12B7J2-01E
2.2 pH Sensor Cable Wiring Procedure
2.2.1 Connecting Sensor Cable
lConnecting Sensor Cable to Terminal Box
(1) Open the cable inlet hole in terminal box using the supplied punch tool. The location of the cable
inlet hole is shown by the circle-shaped groove under the case. The end of the supplied punch
tool is put in the center of this circle and it is tapped with appropriate force. You can punch out the
hole along the groove.
F2.3.ai
Hole punching tool for wiring
(supplied as accessory)
Figure 2.3 How to punch out the wiring hole
(2) Loosen two screws which are at front of terminal box and detach the cover.
(3) After detaching the nut from the cable gland of sensor cable, pull the cable into the terminal box
from sensor cable inlet hole.
Connect the sensor cable to the terminals.
After passing the cable through the nut, check the symbol on each core wire, then connect each
core wire to the corresponding terminal.
CONVERTER
SENSOR
F2.4.ai
Figure 2.4 Connecting Sensor Cable (In case of the PH8TBG)
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< 2. Installation > 2-4
IM 12B7J2-01E
(4) Mount the cable gland in the cable inlet hole.
 Putthenutinplace,andscrewitontothemainbodysu󰀩ciently.Atthistime,loosenthecapso
thatthecableisnottwisted.Afterxingthemainbody,tightenthecaptokeepmoistureoutofthe
equipment. However if the cap is screwed up too tight, the cable will be damaged.
F2.5.ai
Attach the nut in the
direction shown here
(so that it engages
the detent groove).
Nut
Gasket
Main unit
Cap
Figure 2.5 Cable Gland
(5) After completing the cable connections, replace the box cover securely, thus preventing moisture
from getting into the case.
l ConnectingSensorCabletopHTransmitter/Converter
To connect the sensor cable to the two-wire pH transmitter, proceed as follows:
(1) Loosen the four screws that tighten the transmitter cover. Then remove the transmitter cover.
(2) Connect the sensor cables to the relevant terminals of the transmitter/converter:
First, remove the nut from the cable gland. Insert the cable into the right opening for the wiring.
Then pass the cable through the nut, Connect the individual cable conductors to the relevant
terminals correctly by referring to the markings on the individual conductors.
(3) Install the cable gland in the wiring hole as follows:
Pass the tip of the cable gland into the opening and completely tighten the gland with the nut
inside the case.
After tightening the gland, secure the cap properly to prevent moisture from getting into the case.
Caution: Do not overly tighten the cap. Otherwise, the cable may be damaged.
(4) After completing the cable connections, replace the transmitter/converter cover securely, thus
preventing moisture from getting into the case.
For details, refer to the relevant user's manuals for pH transmitter/converter.
2.2.2 Installing the sensor
(1) Mounttheliquidjunctioninthesensorbody.Peelo󰀨thesealattachedtotheliquidjunction
mounting hole in the sensor body. Screw the liquid junction gently two or three turns into the
hole.
(2) The PH8EHP pH sensor comes with a KCl solution reserve tank and its mounting hardware
whenspecied.Attachthemountinghardwaretothepipe(nominaldiameter50mm).
 Whensu󰀩xcode"-TT1"isspecied,connecttheKClsolutionrellingtubeofthesensortothe
general purpose reserve tank holding a 250 mL KCl solution. With the tube connected to the
sensor, remove the cap from the tank and screw the connector of the tube in securely.
 Whensu󰀩xcode"-TT3"isspecied,connecttheKClsolutionrellingtubeofthesensortothe
Big-volume reserve tank holding a 500 mL KCl solution.
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< 2. Installation > 2-5
IM 12B7J2-01E
(3) Supply a KCl solution to the sensor.
For the 250-mL KCl reserve tank, mount the reserve tank on the mounting hardware with the
tube connection part facing down. Using a pin supplied with the tank, make several holes in the
upper part of the sides of the tank (see Figure 2.6).
Stand the sensor upside down at a lower position than the reserve tank as shown in Figure 2.6
sothatKClsolutionowsfromthetankintothesensor.WhentheKClsolutionllsthesensor
andoverowsfromtheliquidjunctionmountinghole,securelyscrewtheliquidjunctionintothe
mounting hole.
CAUTION
How to screw
liquid junction
F2.7.ai
KCl Solution Tube
General Purpose
Reserve Tank
Sensor Body
Liquid Junction (Loose)
Leave air space in the tank.
(Make several holes using the
pin supplied with the tank)
Figure2.6 SupplyingKClSolutiontoSensorBody
For the 500-mL KCl reserve tank, supply a KCl solution to the reserve tank and close the cover.
Be sure to hold the reserve tank by hand when opening or closing the cover. Also, when further
tightening the fixing nut at the bottom of the reserve tank, be careful not to tighten it too tight.
Excessive tightening may cause cracks in the reserve tank.
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Cover
Reserve
Tank
Fixing Nut
KCl Solution
Refilling Tube To pH Sensor
Figure 2.7 500-mL Reserve Tank
B
AWhen you screw the liquid junction into the mounting hole, grip and rotate the “A” (brown body).
If you grip and rotate the “B” (black body), the liquid junction may be broken.
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< 2. Installation > 2-6
IM 12B7J2-01E
CAUTION
After supplying the KCl solution, make sure that no leakage of KCl solutions occurs.
If so, grounding connections will be made at two points. This may cause unstable readings or
measurement errors.
(4) Install the pH sensor to the holder. Insert the pH sensor in the liquid chamber until the liquid
junction in the sensor reaches the bypass in the liquid chamber and secure the sensor with metal
clamp. If the solution does not pass the bypass, remove the sensor from the solution chamber
andsubmergeitinacontainerlledwithwater.
 ThispreventstheglasselectrodefrombeingdryoutorKClsolution—owedoutoftheliquid
junction — from being crystallized.
F2.8.ai
Liquid
chamber
pH sensor
Bypass flow
path assembly
Liquid
junction
Sensor clamp
hardware
Bracket fixing
screw
Grounding
terminal
Measured liquid inlet
Measured liquid
outlet
Stop
valve
Figure 2.8 pH Sensor Installation
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< 3. Maintenance on operation > 3-1
IM 12B7J2-01E
3. Maintenance on operation
3.1 Names of Component
F3.1.ai
Tip type (-H)
Pin type
(-E)
Reserve Tank
KCl Supply Tube
Glass
Electrode
Liquid
Junction
Sensor Body
Ring type
(-G)
Figure 3.1 Names of Component of PH8EHP pH Sensor
11th Edition : Nov.20,2018-00