OEM OPM223 Operating Instructions Manual page 82

Trouble-shooting
Errors Possible cause
No/incorrect temperature
compensation
Conductivity of medium too low
pH value in process Flow too high
wrong
Potential in medium
Sensor contaminated or assigned
Interference on measuring cable
Interference on signal output line
Measured value
fluctuations
Interference potential in medium
No potential matching (PA/PM) for
symmetrical input
Controller switched off
Controller in operating mode
"Manual/off"
Controller/limit contact
does not work
Pick-up delay set too long
"Hold" function active
Controller in operating mode
"Manual/on"
Controller/limit contact Drop-out delay set too long
works constantly
Control circuit interrupted
Line open or short-circuited
No pH/mV current output
signal
Output defective
Current simulation active
Fixed pH/mV current
Impermissible processor system
output signal
operating status
Incorrect current assignment
Incorrect current output
signal
Overall burden in the current loop
too high (> 500 Ω)
Current output table is
Value distance too small
not accepted
No temperature output Device does not have a second
signal current output
Chemoclean function not No relay module (LSR1-x) installed
available or only LSR1-2 available
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Tests and/or remedial measures
ATC: activate function.
MTC: adjust process temperature.
Select pH sensor with liquid KCl.
Reduce flow or measure in a bypass.
Poss. ground with or at PM pin
(connection PM/PE).
Clean sensor (see "Cleaning pH/ORP
sensors" section).
Connect cable as per wiring diagram.
Check line routing, lay line separately if
necessary.
Measure symmetrically (with PML).
Connect PM pin in assembly with
devices PA/PM.
Activate controller.
Select "Auto" or "Manual on" mode.
Switch off or shorten pick-up delay
time.
"Auto hold" for calibration,
"Hold" input activated,
"Hold" active via keyboard.
Set controller to "Manual/off" or "Auto". Keyboard, REL and AUTO keys
Reduce drop-out delay time.
Check measured value, current output
or relay contacts, adjusters, chemical
supply.
Disconnect line and measure directly
at the device.
See "Diagnosis" section.
Switch off simulation.
Switch device off and then on again.
Check current assignment:
0–20 mA or 4–20 mA?
Disconnect output and measure
directly at the device.
Select practical distances.
Check version using nameplate, if
necessary, replace module LSCH-x1.
Install LSR1-4 module.
The Chemoclean is enabled using the
release code supplied by your supplier
in the Chemoclean retrofit kit.
OPM223/253
Tools, spare parts
e.g. OPS41
Problem occurs particularly in plastic
lines.
For heavily contaminated media:
Use spray cleaning.
See "Electrical connection" section.
Signal output and measuring input lines
Poss. ground medium with PM/PE
connection.
See "Relay contact configuration"
section or fields R2xx.
Keyboard, REL key
See fields R2xx.
See fields S2 to S4.
See fields R2xx.
mA metre 0–20 mA DC
See field O2.
EMC problem: if it persists, check the
installation.
Field O211
mA metre for 0–20 mA DC
Module LSCH-x2,
See "Spare parts" section.
Module LSR1-4, see "Spare parts"
section.