ABB RELION 620 Series Technical Manual page 855

1MAC504801-IB E
12.2.1.2
12.2.1.3
620 series ANSI
Technical Manual
User-programmable inverse-time characteristics
The user can define curves by entering parameters into the following standard formula:
 
 
A
 
[ ]
t s B k
= + ⋅
c
 
I
 
 − E
 

I
>
 
 
A060641 V3 EN
t[s] Trip time (in seconds)
A set Curve parameter A
Curve parameter B
B set
Curve parameter C
C set
Curve parameter E
E set
I Measured current
Pickup value
I> set
Time multiplier
k set
RI and RD-type inverse-time characteristics
The RI-type simulates the behavior of electromechanical relays. The RD-type is a ground-
fault specific characteristic.
The RI-type is calculated using the formula


k
t s [ ] =

I >
 
0 339 0 236 . − . ×

I
A060642 V2 EN
The RD-type is calculated using the formula
I

t s [ ] = 5 8 1 35 In . − . ×

k I × >

A060643 V2 EN
General function block features



 




Section 12
(Equation 107)
(Equation 108)
(Equation 109)
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