ABB REB650 - Page 472

Table 404: ANSI Inverse time characteristics
Function Range or value Accuracy
Operating characteristic:
( )
= + ×
-
æ ö
ç ÷
ç ÷
è ø
1
P
A
t B td
I
EQUATION1651 V1 EN
I = I
measured
/I
set
td = (0.05-999) in steps of 0.01 -
ANSI Extremely Inverse A=28.2, B=0.1217, P=2.0
ANSI Very inverse A=19.61, B=0.491, P=2.0
ANSI Normal Inverse A=0.0086, B=0.0185, P=0.02,
tr=0.46
ANSI Moderately Inverse A=0.0515, B=0.1140, P=0.02
ANSI Long Time Extremely Inverse A=64.07, B=0.250, P=2.0
ANSI Long Time Very Inverse A=28.55, B=0.712, P=2.0
ANSI Long Time Inverse A=0.086, B=0.185, P=0.02
Table 405: IEC Inverse time characteristics
Function
Range or value Accuracy
Operating characteristic:
( )
= ×
-
æ ö
ç ÷
ç ÷
è ø
1
P
A
t td
I
EQUATION1653 V1 EN
I = I
measured
/I
set
td = (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
Section 19 1MRK 505 277-UUS C
Time inverse characteristics
466
Technical Manual