Remaining Life Of Circuit Breaker - ABB RELION REX640 Technical Manual

1MRS759142 C
7.1.5.6
REX640
Technical Manual
Accumulated energy calculator
This module calculates the accumulated energy I
the Current exponent setting.
The calculation is initiated with the POSCLOSE input opening events. It ends when
the RMS current becomes lower than the Acc stop current setting value.
GUID-993E5C4D-990B-4B2A-9A13-140403E07958 V1 EN
Figure 690: Significance of the Difference Cor time setting
The Difference Cor time setting is used instead of the auxiliary contact to accumulate
the energy from the time the main contact opens. If the setting is positive, the
calculation of energy starts after the auxiliary contact has opened and when the delay
is equal to the value set with the Difference Cor time setting. When the setting is
negative, the calculation starts in advance by the correction time before the auxiliary
contact opens.
The accumulated energy outputs IPOW_A (_B, _C) are available in the monitored
data view on the LHMI or through tools via communications. The values can be reset
by setting the parameter CB accum. currents power setting to true in the clear menu
from WHMI or LHMI.
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
Condition monitoring functions
y y
t [(kA) s]. The factor y is set with
Section 7
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