Instructions; Application; Requirements; Configuration - ABB REJ 527 Technical Reference Manual

REJ 527
3.
3.1.
3.2.
3.3.
8
Directional or Non-Directional Earth-Fault Relay
Technical Reference Manual

Instructions

Application

The directional or non-directional earth-fault relay REJ 527 is a secondary relay
which is connected to the voltage and current transformers of the object to be
protected. The earth-fault current and the zero-sequence voltage unit continuously
measure the zero-sequence voltage, earth-fault current and phase angle of the object.
On detection of a fault, the relay will start, trip the circuit breaker, provide alarms,
record fault data, etc., in accordance with the application and the configured relay
functions.
The voltage unit includes low-set stage U
stage I > and high-set stage I
0
additional voltage stages, low-set stage U
The protection functions are independent of each other and have their own setting
groups and data recordings. The voltage and current functions use conventional
transformer measurement.
An output contact matrix allows start or trip signals from the protection stages to be
routed to the desired output contact.

Requirements

When the REJ 527 is operating under the conditions specified below (see also
"Technical data"), it will be practically maintenance-free. The relay includes no
parts or components subject to abnormal physical or electrical wear under normal
operating conditions.
Environmental conditions
• Specified ambient service temperature range
• Temperature influence on the operation accuracy of the
protection relay within the specified ambient service
temperature range
• Transport and storage temperature range

Configuration

Setting and connection example
The appropriate configuration of the output contact matrix enables the use of the
signals from the earth-fault current and the voltage unit as contact functions. The
start signals can be used for blocking co-operating protection relays, signalling and
initiating autoreclosing.
Figure 3.3.-1 represents the REJ 527 with the default configuration: all trips are
routed to trip the circuit breaker.
> and the earth-fault current unit low-set
0b
>>. The earth-fault stages can be replaced by two
0
> and high-set stage U
0
1MRS 750616-MUM
>>.
0
-10...+55°C
0.1% / °C
-40...+70°C