ABB RET670 - Inverse Time Characteristics for Overvoltage Protection

Table 120. Inverse time characteristics for overvoltage protection
Function Range or value Accuracy
Type A curve:
=
- >
>
æ ö
ç ÷
è ø
t
k
U U
U
EQUATION1436-SMALL V1 EN
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
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
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
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
Transformer protection RET670 2.0
1MRK 504 141-BEN C
Product version: 2.0
ABB 101