Alstom MiCOM P846, Technical Manual

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P846/EN PL/D Programmable Logic
(PL) 7-16
MiCOM P846
PL
1.8.1 Relay output contact mapping
The default mappings for each of the relay output contacts are as shown in the following
table:
Relay Contact
Number
P846 Relay Text Function
1 Output R1 CVT Alarm output
2 Output R2 Not used in Default PSL
3 Output R3 Open Line Detector trip
4 Output R4 Not used in Default PSL
5 Output R5 Fault Detected indication
6 - 32 Output R6 – Output R32 Not used in Default PSL
1.8.2 Fault recorder start mapping
The default mapping for the signal which initiates a fault record is as shown in the following
table:
Initiating Signal Fault Trigger
Fault detected DDB361 Initiate fault recording from main protection start
The fault record trigger (DDB 691) requires a rising edge for operation. In other words, the
input to the FRT signal must go from a low (de-energized) to a high (energized) state. When
the rising edge occurs, a fault record is generated and the amber Alarm LED is illuminated
(flashing). When a fault record is generated, the data can be viewed on the LCD using the
c
key, and reset by the key if the correct password level is active. Any subsequent fault
record will only be generated on a new rising edge of the fault recorder trigger DDB signal. It
is therefore recommended that all the initiating signals to the fault recorder trigger are self-
resetting.
Note: Since the data is captured on the rising edge, it is possible to clear the
record on the default display even though the initiating signals are still
active. However, the information may still be viewed in the “VIEW
RECORDS” column of the menu.