Table 159. IEC Inverse time characteristics for Sensitive directional residual overcurrent and power protection
Function
Range or value
Accuracy
Operating characteristic:
(
)
1
=
×
-
æ
ö
ç
÷
ç
÷
è
ø
P
A
t
k
I
EQUATION1251-SMALL V1 EN-US
I = I
measured
/I
set
0.05 ≤ k ≤ 2.00
1.5 x I
set
≤ I ≤ 20 x I
set
IEC Normal Inverse
A=0.14, P=0.02
IEC Very inverse
A=13.5, P=1.0
IEC Inverse
A=0.14, P=0.02
IEC Extremely inverse
A=80.0, P=2.0
IEC Short time inverse
A=0.05, P=0.04
IEC Long time inverse
A=120, P=1.0
Table 160. RI and RD type inverse time characteristics for Sensitive directional residual overcurrent and power protection
Function
Range or value
Accuracy
RI type inverse characteristic
1
0.236
0.339
=
×
-
t
k
I
EQUATION1137-SMALL V1 EN-US
I = I
measured
/I
set
0.05 ≤ k ≤ 2.00
1.5 x I
set
≤ I ≤ 20 x I
set
RD type logarithmic inverse characteristic
5.8
1.35
=
-
×
æ
ö
ç
÷
è
ø
t
I
In
k
EQUATION1138-SMALL V1 EN-US
I = I
measured
/I
set
Line distance protection REL650
1MRK 506 384-BEN H
Version 2.2
106
Hitachi Power Grids
© 2017 - 2021 Hitachi Power Grids. All rights reserved
