ABB 1MRK002826-AG - Page 138

Table 192. Inverse time characteristics for residual overvoltage protection
Function Range or value Accuracy
Type A curve:
=
- >
>
æ ö
ç ÷
è ø
t
k
U U
U
EQUATION1436-SMALL V1 EN-US
U> = U
set
U = U
measured
k = (0.05-1.10) in steps
of 0.01
±5.0% or ±45 ms whichever is greater
Type B curve:
2.0
480
32 0.5
=
⋅
− >
⋅ −
0.035+
>
 
 
 
t
k
U U
U
EQUATION1437-SMALL V2 EN-US
k = (0.05-1.10) in steps
of 0.01
Type C curve:
 
3.0
480
32 0.5
=
⋅
⋅ −
− >
0.03
5
+
>
 
 
t
k
U U
U
EQUATION1438-SMALL V2 EN-US
k = (0.05-1.10) in steps
of 0.01
Programmable curve:
×
= +
- >
× -
>
æ ö
ç ÷
è ø
P
k A
t D
U U
B C
U
EQUATION1439-SMALL V1 EN-US
k = (0.05-1.10) in steps
of 0.01
A = (0.005-200.000) in
steps of 0.001
B = (0.50-100.00) in
steps of 0.01
C = (0.0-1.0) in steps of
0.1
D = (0.000-60.000) in
steps of 0.001
P = (0.000-3.000) in
steps of 0.001
Generator protection REG670
1MRK 502 074-BEN M
Version 2.2
138 Hitachi Power Grids
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