ABB RET650 Technical Manual page 638

Section 21
Time inverse characteristics
632
Table 560: IEC Inverse time characteristics
Function
Operating characteristic:
æ ö
A
ç ÷
= ×
t k
( )
ç ÷
P
è - ø
I 1
EQUATION1251-SMALL V1 EN
I = I /I
measured set
IEC Normal Inverse
IEC Very inverse
IEC Inverse
IEC Extremely inverse
IEC Short time inverse
IEC Long time inverse
The parameter setting Characterist1 and 4/Reserved shall not be used,
since this parameter setting is for future use and not implemented yet.
Table 561: RI and RD type inverse time characteristics
Function
RI type inverse characteristic
1
= ×
t k
0.236
-
0.339
I
EQUATION1137-SMALL V1 EN
I = I /I
measured set
RD type logarithmic inverse characteristic
æ ö
I
- ç × ÷
= 5.8 1.35 In
t
è ø
k
EQUATION1138-SMALL V1 EN
I = I /I
measured set
Range or value
k = (0.05-999) in steps of 0.01
A=0.14, P=0.02
A=13.5, P=1.0
A=0.14, P=0.02
A=80.0, P=2.0
A=0.05, P=0.04
A=120, P=1.0
Range or value
k = (0.05-999) in steps of 0.01
k = (0.05-999) in steps of 0.01
1MRK 504 135-UEN A
Accuracy
-
Accuracy
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