
Measured circuit breaker opening and closing times are shown in the
monitored data with outputs
CB_OPN_T_CB1
,
CB_OPN_T_CB2
,
CB_CLS_T_CB1
and
CB_CLS_T_CB2
.
An alarm is issued in case circuit breaker opening or closing time exceeds the set
limits. Opening time alarm limit is set with setting
CB open alarm time and closing
time alarm limit is set with setting
CB close alarm time.
An alarm is also issued in case closing time between consecutive closings varies
more than set by setting
CB closing time Dif.
Alarm outputs are
AL_OPN_CB1
and
AL_CLS_CB1
for circuit breaker 1 and
AL_OPN_CB2
and
AL_CLS_CB2
for circuit breaker 2.
Circuit breaker closing time measurement, “From Cmd to Pos”
“From Cmd to Pos” mode measures the closing time from binary output activation
till position change has been indicated by auxiliary contacts.
shows an example of CB closing time measurement in “From Cmd to
Pos” mode.
POSOPN_CB2 – AUX BIN
POSCLS_CB2 – AUX BIN
Current in Feeder 2 / CB2
OPEN_CB2 – FB CMD
CLOSE_CB2 – FB CMD
RELAY BINARY OUTPUT
Closing
�m
e
1 2
4
3
Internal Logic + BO ac
�
va
�
on delay
Figure 949: Circuit breaker closing time measurement (“From Cmd to Pos”)
1
HSABTC function activates
CLOSE_CB2
output
2
Relay binary output activates – closing time measurement starts from this
point
3
Circuit breaker main contacts close
4
Close position indicated to relay with auxiliary contacts
Closing time is time from 2 to 4
1MRS759142 F
Control functions
REX640
Technical Manual
1783