Inputs - ABB REU 523 Technical Reference Manual

1MRS 750942-MUM
4.1.1.3.
4.1.1.4.
4.1.1.5.
4.1.1.6.
4.1.1.7.
4.1.1.8.
Combined Overvoltage and Undervoltage Relay
Technical Reference Manual

Inputs

The REU 523 includes three energizing inputs and one external binary input
controlled by an external voltage. For details, refer to section Input/output
connections and tables 4.1.4.6-6, 4.2.1-1 and 4.2.1-5. The function of the binary
input is determined with the SGB switches.
Outputs
The REU 523 is provided with two power outputs (PO1 and PO2) and two signal
outputs (SO1 and SO2). Switchgroups SGR1...8 are used for routing start and trip
signals from the protection stages to the desired signal or power output. PO1 and
PO2 can be configured to be latched and the minimum pulse length to 40 or 80 ms.
Circuit-breaker failure protection unit
The REU 523 features a circuit-breaker failure protection (CBFP) unit. The CBFP
unit will generate a trip signal via output PO2 if the fault has not been cleared on
expiration of the set operate time 0.10 s...1.00 s.
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. The CBFP unit is
activated with a switch of switchgroup SGF1.
Disturbance recorder
The REU 523 includes an internal disturbance recorder which records the
momentary measured values, or the RMS curves of the measured signals, and eight
digital signals: the external binary input signal and the states of the internal
protection stages. The disturbance recorder can be set to be triggered by a start or a
trip signal from any protection stage and/or by an external binary input signal, and
either on the falling or rising triggering edge.
HMI module
The HMI of the REU 523 is equipped with six push-buttons and an alphanumeric
2x16 characters' LCD. The push-buttons are used for navigating in the menu
structure and for adjusting set values.
An HMI password can be set to protect all user-changeable values from being
changed by an unauthorised person. The HMI password will remain inactive and
will thus not be required for altering parameter values until the default HMI
password has been replaced. Entering the HMI password successfully can be
selected to generate an event code. This feature can be used to indicate interaction
activities via the local HMI. For further information on the HMI, refer to the
Operator's Manual.
Non-volatile memory
The REU 523 can be configured to store various data in the non-volatile memory,
which will retain its data also in case of loss of auxiliary voltage. Alarm indication
messages and LEDs, the number of starts, disturbance recorder data, event codes and
recorded data can all be configured to be stored in the non-volatile memory whereas
setting values will always be stored.
REU 523
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