Woodward MRM4, Manual, Page: 414 / 460

Supervision
Name Description Assignment via
CB Pos Detect-I Module input state: Criterion by which the
Circuit Breaker Switch Position is to be
detected. [Protection Para
/Global Prot Para
/Supervision
/TCS]
Trip Circuit Supervision Signals (Output States)
Name Description
active Signal: active
ExBlo Signal: External Blocking
Alarm Signal: Alarm Trip Circuit Supervision
Not Possible Not possible because no state indicator assigned to the breaker.
Commissioning: Trip Circuit Supervision [74TC]
For CBs that trip by means of little energy (e.g. via an optocoupler), it has
to be ensured that the current applied by the digital inputs will not cause
false tripping of the CB.
Object to be tested
Test of the trip circuit supervision.
Procedure, part 1
Simulate failure of the control voltage in the power circuits.
Successful test result, part 1
After expiry of »t-TCS« the trip circuit supervision TCS of the device should signal an alarm.
Procedure, part 2
Simulate a broken cable in the CB control circuit.
Successful test result, part 2
After expiry of »t-TCS« the trip circuit supervision TCS of the device should signal an alarm.
CTS - Current Transformer Supervision [60L]
Available elements:
CTS
Wire breaks and failures within measuring circuits cause current transformer failures.
The module »CTS« can detect a failure of the CT if the calculated earth current does not match the measured
one. If an adjustable threshold value (Difference of measured and calculated earth current) is exceeded, a CT
failure can be assumed. This is signalled through a message/alarm.
The precondition is that the conductor currents are measured by the device and the earth current, for instance,
Page 414 EN MRM4 01/11