Endress+Hauser Liquisys M CCM223 - Page 91

Liquisys M CCM223/253 Diagnostics and troubleshooting
Endress+Hauser 91
Error Possible cause Tests/remedial action Tools, spare parts
Device in impermissible
operating condition (does
not respond when key
pressed)
Disconnect line voltage for
approx. 10 seconds
Possibly EMC problem: if
problem persists, check
grounding and wire
routing.
Incorrect
temperature value
Incorrect sensor
connection
Check connections using wiring
diagram. Three-wire connection
always required
Wiring diagram in
"Electrical connection"
section
Sensor or measuring cable
defective
Check sensor and cable Ohmmeter
Incorrect pH
measured value in
the process
Flow too high Reduce flow or measure in a
bypass.
Potential in medium Possibly ground with or/at PM
pin (connect PA/PM with PE).
Problem mainly occurs in
plastic lines.
Sensor fouling or buildup
on sensor
Clean sensor For heavily contaminated
media: use spray cleaning
Fluctuations in
measured value
Interference on measuring
cable
Connect cable shield as per
wiring diagram
See the "Electrical
connection" section
Interference on signal
output cable
Check cable routing, possibly
route cable separately
Route signal output and
measuring input lines
separately
Interference potential in
medium
Eliminate source of interference
or ground medium as close as
possible to sensor.
No potential matching on
symmetrical input
Connect PM pin in assembly to
device terminal PA/PM.
Controller or timer
cannot be
activated
No relay module available Install LSR1-2 or LSR1-4
module
Controller/limit
contact does not
work
Controller switched off Activate controller See fields R2xx
Controller in operating
mode "Manual off"
Select "Auto" or "Manual on"
mode
Keyboard, REL key
Pickup delay setting too
long
Switch off or shorten pickup
delay time
See fields R2xx
"Hold" function active “Auto hold” for calibration,
“Hold” input activated;
“Hold” active via keyboard
See fields S2 to S4
Controller/limit
contact works
continuously
Controller in operating
mode "Manual on"
Select "Auto" or "Manual off"
mode
Keyboard, REL and AUTO
keys
Dropout delay setting too
long
Shorten dropout delay time See fields R2xx
Control loop interruption Check measured value, current
output value, actuators,
chemical supply
No current output
signal
Cable disconnected or
short-circuited
Disconnect cable and measure
directly at device
mA meter 0–20 mA
Output defective See the "Device-specific errors"
section
Fixed current
output signal
Current simulation active Switch off simulation. See field O3
Impermissible operating
state of processor system
Disconnect line voltage for
approx. 10 seconds
Possibly EMC problem: if
problem persists, check
grounding and wire
routing.
Incorrect current
output signal
Incorrect current
assignment
Check current assignment: 0–
20 mA or 4–20 mA?
Field O311