Alstom MiCOM P54 Series, Technical Manual, Page: 371 / 1024

Operation P54x/EN OP/La4
MiCOM P543, P544, P545 & P546
(OP) 5-197
OP
For either circuit breaker, at the completion of any dead time or follower time, the logic starts
an
AR CBHealthy timer
. If the
CB Healthy
signal (DDB 436 or 437) becomes high before
the set time is complete, the timer stops and, if all other relevant circuit breaker closing
conditions are satisfied the scheme issues the
CB AutoClose
signal. If the
CB Healthy
signal, (DDB 436 or 437) signal stays low, then at the end of the set
AR CBHealthy time
an
AR CB Unhealthy
alarm signal (DDB 307 or 329) is set. This forces the circuit breaker
auto-reclose sequence to be cancelled.
Additionally, for either circuit breaker, at the completion of any three phase dead time or
three phase follower time, the logic starts an
AR CheckSync Time
. If the circuit breaker
synchro-check OK signal {“CB L SCOK “ (DDB 1573 or1455) or
CB F SCOK
(DDB1491
or1456)} goes high before the set time is complete, the timer stops and, if all other relevant
circuit breaker closing conditions are satisfied, the scheme issues the
CB AutoClose
signal.
If the
System check OK
signal stays low, then at the end of the
AR CheckSync Time
an
alarm
AR CB No C/S
(DDB 308 or 330) is set which informs that the check synchronism is
not satisfied for that circuit breaker and forces the auto-reclose sequence to be cancelled.
5.6.6.14 CB1 & CB2 auto-reclose shots counters (P544/P546)
The CB1 & CB2 auto-reclose shots counter logic is shown in AR Figure 41and Figure 42
(logic diagram supplement).
A number of counters are provided to enable analysis circuit breaker auto-reclosing history.
Each circuit breaker has a set of counters that are stored in non-volatile memory, so that the
data is maintained even in the event of a failure of the auxiliary supply.
Logic signals from the
Sequence counters
is combined with
successful auto-reclose
signals and
auto-reclose lockout
signals to provide the following summary for each circuit
breaker:-

Overall total shots (No. of reclose attempts);

CBx Total Shots

Number of successful single phase reclosures;

CBx SUCC SPAR

Number of successful 1st shot three phase reclosures;

CBx SUCC3PARShot1

Number of successful 2nd shot three phase reclosures;

CBx SUCC3PARShot2

Number of successful 3rd shot three phase reclosures;

CBx SUCC3PARShot3

Number of successful 4th shot three phase reclosures;

CBx SUCC3PARShot4

Number of failed auto-reclose cycles which forced CB to lockout.

CBx Failed Shots
All the counter contents are accessible through the CB CONTROL column of the menu.
For each individual circuit breaker, these counters can be reset either by user commands
Reset CB1 Shots
or
Reset CB2 Shots
from the CB CONTROL settings column, or by
activation of the relevant input
Ext Rst CB1 Shots
or
Ext Rst CB2 Shots
(DDB 1518 or
1418) mapped in the PSL.