Inverse Characteristics - ABB REG670 Technical Manual

1MRK502052-UEN B
25.3
Technical manual
In version 2.0, a typical starting time delay of 24ms is subtracted from
the set trip time delay, so that the resulting trip time will take the
internal IED start time into consideration.

Inverse characteristics

Table 959: ANSI Inverse time characteristics
Function
Operating characteristic:
æ ö
A
ç ÷
= + × +
t B k tDef
( )
ç ÷
P
ç - ÷
I 1
è ø
EQUATION1249-SMALL V2 EN
Reset characteristic:
t r
= ×
t k
( )
2
-
I 1
EQUATION1250-SMALL V1 EN
I = I /I
measured set
ANSI Extremely Inverse
ANSI Very inverse
ANSI Normal Inverse
ANSI Moderately Inverse
ANSI Long Time Extremely Inverse
ANSI Long Time Very Inverse
ANSI Long Time Inverse
Inverse time characteristics
Range or value
k = (0.05-2.00) in steps of 0.01
A=28.2, B=0.1217, P=2.0 ,
tr=29.1
A=19.61, B=0.491, P=2.0 ,
tr=21.6
A=0.0086, B=0.0185, P=0.02,
tr=0.46
A=0.0515, B=0.1140, P=0.02,
tr=4.85
A=64.07, B=0.250, P=2.0,
tr=30
A=28.55, B=0.712, P=2.0,
tr=13.46
A=0.086, B=0.185, P=0.02,
tr=4.6
Section 25
Accuracy
ANSI/IEEE C37.112 ,
± 2.0% or ± 40 ms
whichever is greater
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