x/EN PL/Na7 
 
 7-
 
MiCOM P74
 
 
Relay 
English Text  Type  Source  Description 
Manual Trip Order of a zone, general 
information common to all PUs, the PU can be 
connected to an healthy zone 
Fault in the dead zone on a phase 
Fault in the dead zone on the neutral 
Valid Setting configuration 
All the protections (CU & PU) disabled 
Circuit Breaker Healthy (Can Trip) 
External or internal Breaker failure trip order 
request (50BF) Logical OR of DDB 122, 172 
Logic input to block the 87BB trip when the fault 
is detected by the fault element 
Logic input to block the 87BB trip when the fault 
is detected by the earth fault element 
Logical OR of ddb 121 and 270 
Manual Trip Order of the Circuit Breaker 
Manual closing order of the Circuit Breaker 
PU in 50BF blocked mode Alarm 
To switch the PU in 50BF blocked mode 
To switch the PU in overhaul mode 
Overcurrent Local trip confirmation 
Fast external phase fault criterion to block the 
connected zone enabled 
Fast external neutral fault criterion to block the 
connected zone enabled 
Change on topology or configuration 
Isolator 1 closed (not (Q1 Aux. (89b) AND Q1 
Aux. (89a))) 
Isolator 1 discrepancy (Q1 Aux. (89b) = Q1 
Aux. (89a) for too long 
Isolator 6 closed (not (Q6 Aux. (89b) AND Q6 
Aux. (89a))) 
Isolator 6 discrepancy (Q6 Aux. (89b) = Q6 
Aux. (89a) for too long 
Circuit Breaker closed (not (CB Aux. (52b) AND 
CB Aux. (52a))) 
Isolator 1 status position forced open (by 
default) or closed 
Isolator 6 status position forced open (by 
default) or closed 
CB status position forced open (by default) or 
closed  
When the forced positions of the CB and the 
Isolators are used (during commissioning test) 
ddb 123 or Logical OR of ddb 125 and 127 and 
129 
ddb 124 or Logical AND of ddb 126 and 128 
and 130 
Triphase Circuit Breaker Trip from CU (Init 
50BF TBF1 / TBF2), Logical OR of : 
87BB, 50BF, Manual Trip Zone X