Endress+Hauser Topcal S CPC310, Руководство по эксплуатации

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Troubleshooting
141
Fixed, incorrect measured
value
Sensor not immersed or protection cap
not removed Check installation position, remove protec-
tion cap
Air cushion in assembly Check assembly and orientation
Earth fault at or in the instrument
Perform test measurement in insulated
vessel, with buffer solution where necessary Plastic vessel, buffer solutions; behavior if
connection to process established?
Hairline crack in glass membrane Replace sensor pH sensor
Device has unpermitted operating
status (no reaction to key being pressed)
Switch device off and on again.
EMC problem: If the problem persists, check
grounding, shielding and conduits or have
checked by Hauser service.
Incorrect temperature sensor
connection Check connections using the wiring
diagram Wiring diagram, "Electrical connection"
section
Measuring cable defective
Check cable for
disconnection/short-circuit/shunt
Ohmmeter
Incorrect temperature
reading
Wrong sensor type
Set the type of temperature sensor at the
device (Set up 1 > Temperature) Glass electrode: Pt 100
ISFET: Pt 1000
Temperature sensor defective Check sensor
pH value in process
incorrect
No / incorrect temperature
compensation ATC: Activate function
MTC: Set process temperature
Conductivity of medium too low Select pH sensor with liquid KCl e.g. Ceraliquid CPS41, Purisys CPF201
Flow rate too high Reduce flow or measure in a bypass
Potential in medium
Where necessary, ground with or at PM pin
(PM/PE connection)
Problem occurs in plastic pipes in particular.
Device unsymmetrical and PM
connected
Remove PML connection to PM terminal;
where necessary ground with/at PM pin
(PM connection after PE)
Sensor fouled or assigned
Clean sensor (see "Cleaning pH/redox
sensors" section) For very contaminated media:
Use spray cleaning.
Interference in measuring cable Connect cable shield as per wiring diagram. See "Electrical connection" section.
Measured value fluctuations
Interference on signal output cable
Check cable routing, route cable separately
where necessary.
Signal output and measuring input cables
Interference potential in medium Measure symmetrically (with PML).
Where necessary, ground medium with
PM/PE.
No potential matching (PA/PM) with
symmetrical input Connect PM pin in assembly with device
PA/PM.
Controller / limit contact
not working
Controller switched off Activate controller. See "Set up 1 > Relays" section.
Controller in “Manual / Off” mode
Select "Automatic" or "Manual on"
operating mode.
Key pad,
Ñ
> Manual operation > Relays
Pickup delay setting too long Switch off or shorten pickup delay time. See "Set up 2 - Limit switch" section.
"Hold" function active
“Auto-hold” with calibration,
“Hold” input activated,
Manual “Hold” via keypad active,
"Hold" active during configuration
Determine and eliminate reason for Hold if
not desired
"Hold" is shown on display if active.
Controller / limit contact
work continuously
Controller in “Manual / On” mode
Set controller to "Manual / Off" or
"Automatic".
Key pad > Manual operation > Relays
Dropoff delay setting too long Reduce dropoff delay time. See "Set up 2 - Limit switch" section.
Closed-control loop interrupted
Check measured value, current output or
relay contacts, adjusters, chemical supply.
Error Possible cause Tests and / or remedial action Equipment needed, spare parts