ABB RELION REX640 Technical Manual page 1667

1MRS759142 C
REX640
Technical Manual
The operate 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
>
 
 
GUID-EA790CC7-7408-47B9-A11E-2C65EDB4D4F4 V1 EN
t[s] Operate time in seconds
I Measured current
Start value
I> Set
Time multiplier
k Set
Table 1472: Curve parameters for ANSI and IEC IDMT curves
Curve name A
(1) ANSI Extremely 28.2
Inverse
(2) ANSI Very Inverse 19.61
(3) ANSI Normal 0.0086
Inverse
(4) ANSI Moderately 0.0515
Inverse
(6) Long Time 64.07
Extremely Inverse
(7) Long Time Very 28.55
Inverse
(8) Long Time Inverse 0.086
(9) IEC Normal Inverse 0.14
(10) IEC Very Inverse 13.5
(11) IEC Inverse 0.14
(12) IEC Extremely 80.0
Inverse
(13) IEC Short Time 0.05
Inverse
(14) IEC Long Time 120
Inverse
General function block features
B
0.1217
0.491
0.0185
0.1140
0.250
0.712
0.185
0.0
0.0
0.0
0.0
0.0
0.0
Section 11
(Equation 354)
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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