ABB RER620, Technical Manual

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1MAC309294-MB F
Section 6
Condition monitoring functions
RER620 365
Technical Manual
Figure 199: 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 through the Monitored
data view on the LHMI or through tools via communications. The values can be reset by
setting the parameter
CBCMx acc. energy 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
.
6.1.4.6 Remaining life of the 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 by
using a module diagram. All the modules in the diagram are explained in the next sections.
Main Contact
POSCLOSE_A
0
1
open
close
Energy
accumulation starts
Difference Cor time
(Negative)
Main Contact
POSCLOSE_A
0
1
open
close
Energy
accumulation starts
Difference Cor time
(Positive)