ABB RELION 620 Series Technical Manual page 575

1MAC504801-IB E
6.1.4.6
620 series ANSI
Technical Manual
Alarm limit check
The IPOW_ALM alarm is activated when the accumulated energy exceeds the value set
with the Alm Acc currents Pwr threshold setting. However, when the energy exceeds the
limit value set with the LO Acc currents Pwr threshold setting, the IPOW_LO output is
activated.
The IPOW_ALM and IPOW_LO outputs can be blocked by activating the binary input
BLOCK.
Remaining life of circuit breaker
Every time the breaker operates, the life of the circuit breaker reduces due to wearing. The
wearing in the breaker depends on the tripping current, and the remaining life of the
breaker is estimated from the circuit breaker trip curve provided by the manufacturer. The
remaining life is decremented at least with one when the circuit breaker is opened.
The operation of the remaining life of the circuit breaker subfunction can be described
with a module diagram. All the modules in the diagram are explained in the next sections.
A071111 V2 EN
Figure 285: Functional module diagram for estimating the life of the circuit breaker
Circuit breaker life estimator
The circuit breaker life estimator module calculates the remaining life of the circuit
breaker. If the tripping current is less than the rated operating current set with the Rated Op
current setting, the remaining operation of the breaker reduces by one operation. If the
tripping current is more than the rated fault current set with the Rated fault current setting,
the possible operations are zero. The remaining life of the tripping current in between
these two values is calculated based on the trip curve given by the manufacturer. The Op
number rated and Op number fault parameters set the number of operations the breaker
can perform at the rated current and at the rated fault current, respectively.
The remaining life is calculated separately for all three phases and it is available as a
monitored data value CB_LIFE_A (_B,_C). The values can be cleared by setting the
parameter CB wear values in the clear menu from WHMI or LHMI.
Section 6
Supervision functions
569