ABB RED650 - Page 893

Table 675: Inverse time characteristics for undervoltage protection
Function Range or value Accuracy
Type A curve:
=
< -
<
æ ö
ç ÷
è ø
k
t
U U
U
EQUATION1431-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
0.055
32 0.5
×
= +
< -
× -
<
æ ö
ç ÷
è ø
k
t
U U
U
EQUATION1432-SMALL V1 EN-US
U< = U
set
U = U
measured
k = (0.05-1.10) in
steps of 0.01
Programmable curve:
×
= +
< -
× -
<
é ù
ê ú
ê ú
ê ú
æ ö
ê ú
ç ÷
ëè ø û
P
k A
t D
U U
B C
U
EQUATION1433-SMALL V1 EN-US
U< = U
set
U = U
measured
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
1MRK 505 394-UEN A Section 25
Inverse time characteristics
Line differential protection RED650 2.2 IEC 887
Technical manual