ABB RELION 620 Series Technical Manual page 841

1MAC504801-IB E
620 series ANSI
Technical Manual
The trip times for the ANSI and IEC IDMT curves are defined with the coefficients A, B
and C.
The values of the coefficients can be calculated according to the formula:
 
 
A
 
t s [ ] = + B k ⋅
 
c
I
 
 
 − 1

 
I >
 
 
A060821 V2 EN
t[s] t[s] = Trip time in seconds
I measured current
Pickup value
I> set
k set Time multiplier
Table 612: Curve parameters for ANSI and IEC IDMT curves
Curve name
(1) ANSI Extremely
Inverse
(2) ANSI Very Inverse
(3) ANSI Normal Inverse
(4) ANSI Moderately
Inverse
(6) Long Time Extremely
Inverse
(7) Long Time Very
Inverse
(8) Long Time Inverse
(9) IEC Normal Inverse
(10) IEC Very Inverse
(11) IEC Inverse
(12) IEC Extremely
Inverse
(13) IEC Short Time
Inverse
(14) IEC Long Time
Inverse
General function block features
A B
28.2 0.1217
19.61 0.491
0.0086 0.0185
0.0515 0.1140
64.07 0.250
28.55 0.712
0.086 0.185
0.14 0.0
13.5 0.0
0.14 0.0
80.0 0.0
0.05 0.0
120 0.0
Section 12
(Equation 106)
C
2.0
2.0
0.02
0.02
2.0
2.0
0.02
0.02
1.0
0.02
2.0
0.04
1.0
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