ABB RER620, Техническое руководство, Страница: 374 / 584

Section 6
1MAC309294-MB F
Condition monitoring functions
368 RER620
Technical Manual
Figure 202: Functional module diagram for circuit breaker gas pressure alarm
The gas pressure is monitored through the binary input signals
PRES_LO_IN
and
PRES_ALM_IN
.
Timer 1
When the PRES_ALM_IN binary input is activated, the PRES_ALM alarm is activated
after a time delay set with the Pressure alarm time setting. The
PRES_ALM
alarm can be
blocked by activating the
BLOCK
input.
Timer 2
If the pressure drops further to a very low level, the
PRES_LO_IN
binary input becomes
high, activating the lockout alarm
PRES_LO
after a time delay set with the Pres lockout
time setting. The PRES_LO alarm can be blocked by activating the BLOCK input.
6.1.5 Application
52CM includes different metering and monitoring subfunctions.
Circuit breaker status
Circuit breaker status monitors the position of the circuit breaker, that is, whether the
breaker is in an open, closed or intermediate position.
Circuit breaker operation monitoring
The purpose of the circuit breaker operation monitoring is to indicate that the circuit
breaker has not been operated for a long time. The function calculates the number of days
the circuit breaker has remained inactive, that is, has stayed in the same open or closed
state. There is also the possibility to set an initial inactive day.
Breaker contact travel time
High travelling times indicate the need for maintenance of the circuit breaker mechanism.
Therefore, detecting excessive travelling time is needed. During the opening cycle
operation, the main contact starts opening. The auxiliary contact A opens, the auxiliary
contact B closes, and the main contact reaches its opening position. During the closing
cycle, the first main contact starts closing. The auxiliary contact B opens, the auxiliary
contact A closes, and the main contact reaches its close position. The travel times are