Response Of Outputs To Errors - Endress+Hauser Mycom S CPM 153 Operating Instructions Manual

8 Troubleshooting
Error
Incorrect measured pH Transmitter module defective
/ mV value and / or (module: MKP2), please carry out
measured temperature tests and measures first as descri-
value bed in Chap. 8.1.2
Current output, Calibration incorrect
Current value incorrect
Load too high
Shunt / short-circuit to frame in cur-
rent circuit
Incorrect operating mode
No current output signal Current output stage defective
(Module: M3CH-x)
Instrument with PROFIBUS
interface
102
Possible cause
®
8.2

Response of outputs to errors

8.2.1 Current output behaviour
If an error occurs in the system, an error current is output at the current output. You can
adjust the value of this error current in the Alarm menu (see page 43).
If you have configured the controller for functioning with a current output, no error cur-
rent is output on this current output should an error occur.
8.2.2 Response of contacts to errors
You can select the assignment of which instrument error messages trigger an alarm
individually for each error message (see table on page 93, editing errors on page 44).
In "NAMUR" mode, failure messages (E 001 – E 029) always trigger an alarm.
Behaviour with standard setting
Instrument status
Normal operation
Alarm
Voltage-free
Tests and / or remedial
action
Test measuring inputs:
Connect pH, Ref and PM directly on
the instrument with wire jumpers:
Display must be pH 7
Resistance 100 Ω of
Terminals 11 to 12+ 13.
Display must be 0°C
Test with integrated current simulation,
connect mA meter directly to current
output
Check, whether 0–20 mA or 4–20 mA
is selected
Test with integrated current simulation,
connect mA meter directly to current
output
®
PROFIBUS instruments do not have a
current output
Alarm relay
picked-up (Fail-safe behaviour)
Dropped out
Dropped out
Mycom S CPM 153
Equipment, spare parts,
personnel
If test negative: Replace module
MKP2, performed using installation
diagram page 105
If simulation value incorrect: new
module M3Cx-x required.
If simulation value correct:
check current circuit for load and
shunts
If test negative:
Replace module M3CH-x
(Check variants, see spare parts list
in Chap. 8.3)
For information, see "DIAG" / internal
data
Limit value / Controller
Appropriate
configuration and
operating status
Dropped out
Endress+Hauser