REJ 523
Technical Reference Manual
ABB Substation Automation
Products and Systems
MRS750940-MUM
10
4.1.1.2 Overcurrent
Refer to section 4.1.3.1 Overcurrent unit.
4.1.1.3 Inputs
The relay includes three energizing inputs for phase currents and one external binary
input controlled by an external voltage. The function of the binary input is determined
with selector switches of the protection relay. For inputs, see also section 4.2.1 Input /
output connections and tables 4.1.3.3-5, 4.2.1-1 and 4.2.1-5.
4.1.1.4 Outputs
The relay is provided with two power outputs (PO1 and PO2), and two signal outputs
(SO1 and SO2). Switchgroups SGR1...4 are used for routing the start and trip signals
of any protection stage to the desired signal or power output.
4.1.1.5
Circuit-breaker failure protection
The relay features a circuit-breaker failure protection (CBFP) unit. The CBFP unit
generates a trip signal via output PO2 after the set operate time 0.1 s...1 s if the fault
has not been cleared by that time.
Normally, the CBFP unit controls the upstream circuit breaker. It can also be used for
tripping via redundant trip circuits of the same circuit breaker if the circuit breaker is
provided with two trip coils. The circuit-breaker failure protection unit is activated
with a switch of switchgroup SGF.
4.1.1.6 Disturbance
recorder
The relay includes an internal disturbance recorder, which records momentary values,
internal logic signals and external BI signal. The disturbance recorder can be set to be
triggered on operation of stages or on an external BI signal, either on the falling or
rising trigger edge.
Summary of Contents for REJ 523
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