Inverse Definite Minimum Time Characteristcs; Settings; Triggering - ABB REU 610 Technical Reference Manual

1MRS755769
5 . 1. 4 . 6.
Voltage Relay
Technical Reference Manual
The CBF P can also be selected to be triggered ex ternally by applying a digital
input signal to the relay, if the max imum of all three phase- to- phase voltages
is above 0.15 × U . If the fault situation is not cleared when the set operate
n
time has elapsed, the CBF P generates a trip signal via output PO2.
Internal triggering is selected by activating the CBF P in S GF 1/ 6 and ex ternal
triggering by activating the CBF P in S GB1...5 / 7 .
N ormally, the CBF P controls the upstream circuit breaker. H owever, it can
also be used for tripping via redundant trip circuits of the same circuit
breaker.
I n v er s e d ef i n i te m i n i m u m
E ach of the overvoltage and undervoltage stages can be given either a
definite- time or an inverse definite minimum time ( ID M T) characteristic. The
following setting parameters determine the operation mode of the overvoltage
and undervoltage protection stages:
Table 5 .1.4.6.-1 Operation mode s etting parameters
P r otec ti on P ar am eter
s tage
U> S3
U> > / U > S11
2
U< S15
U< < / U < S22
1
At ID M T characteristic, the operate time of the stage is dependent on the
voltage value: the greater the deviation from the setting value, the shorter the
operate time. Three time/ voltage curve groups are available: A, B and C.
An overvoltage stage starts when the measured voltage ex ceeds the setting
value of the stage. An undervoltage stage starts when the measured voltage
drops below the setting value of the stage. H owever, the ID M T calculation
does not start until the deviation between the measured voltage and the setting
value ex ceeds 3 percent. The operate time accuracy stated in technical data
applies when the deviation is 10 percent or higher.
ti m e c h ar ac ter i s tc s
S etti n g
0 = definite time
1 = curve A
2 = curve B
0 = definite time
1 = curve A
2 = curve B
0 = definite time
1 = curve C
0 = definite time
1 = curve C
REU 610
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