Table 94. IEC Inverse time characteristics
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
0.10 ≤ k ≤ 3.00
1.5 x I
set
≤ I ≤ 20 x I
set
IEC 60255-151, ±2.0%
or ±40 ms whichever is
greater
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
Programmable characteristic
Operate characteristic:
(
)
=
+
×
-
æ
ö
ç
÷
ç
÷
è
ø
P
A
t
B
k
I
C
EQUATION1370-SMALL V1 EN-US
Reset characteristic:
(
)
=
×
-
PR
TR
t
k
I
CR
EQUATION1253-SMALL V1 EN-US
I = I
measured
/I
set
k = (0.05-999) in steps of 0.01
A=(0.005-200.000) in steps of 0.001
B=(0.00-20.00) in steps of 0.01
C=(0.1-10.0) in steps of 0.1
P=(0.005-3.000) in steps of 0.001
TR=(0.005-100.000) in steps of 0.001
CR=(0.1-10.0) in steps of 0.1
PR=(0.005-3.000) in steps of 0.001
Table 95. RI and RD type inverse time characteristics
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
0.10 ≤ k ≤ 3.00
1.5 x I
set
≤ I ≤ 20 x I
set
IEC 60255-151, ±2.0%
or ±40 ms whichever is
greater
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
1MRK 505 362-BEN B
Busbar protection REB650 2.1 IEC
Product version: 2.1
ABB
55