ABB REJ 527, Technical Reference Manual

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1MRS 750616-MUM Directional or Non-Directional Earth-Fault Relay
Technical Reference Manual
REJ 527
4.1.1.9. Self-supervision
The self-supervision system of the REJ 527 manages run-time fault situations and
informs the user about an existing fault. When the self-supervision system detects a
permanent internal relay fault, the READY indicator LED will start to blink. At the
same time the self-supervision alarm relay (also referred to as the IRF relay), which
is normally picked up, will drop off and a fault code will appear on the LCD. The
fault code is numerical and identifies the fault type. For fault codes, refer to section
Internal fault in the Operator’s Manual.
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Fault codes can indicate:
• no response on the output contact test
• faulty program, work or parameter memory
• internal reference voltage error
4.1.2. Measurements
The table below presents the measured values which can be accessed through the
HMI. The measured voltage is shown as a percentage of the rated voltage, U
n
, and
the measured currents of the rated current, I
n
, of the energizing input. The phase
angle is shown in degrees and can be selected to be shown either as the angle
between the voltage and the current or as the angle between the basic angle and the
current with switch SGF3/8. If the measured current and voltage values are too low,
i.e. lower than 0.50 percent, dashes will be shown on the LCD.
Faultc
C
E
START READY TRIP
INTERNAL FAULT
FAULT CODE :56
Table 4.1.2-1 Measured values
Indicator Measured data
U
0
Zero-sequence voltage
I
0
Earth-fault current
I
ϕ
Directional earth-fault current
ϕ
Phase angle