ABB REC650 - Page 624

Table 574: 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
I = I
measured
/I
set
k = (0.05-999) in steps of 0.01 -
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
The parameter setting Characterist1 and 4/Reserved shall not be used,
since this parameter setting is for future use and not implemented yet.
Table 575: 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
I = I
measured
/I
set
k = (0.05-999) in steps of 0.01
RD type logarithmic inverse characteristic
5.8 1.35= - ×
æ ö
ç ÷
è ø
t
I
In
k
EQUATION1138-SMALL V1 EN
I = I
measured
/I
set
k = (0.05-999) in steps of 0.01
Section 19 1MRK 511 287-UEN A
Time inverse characteristics
618
Technical manual