GUID-19F8E187-4ED0-48C3-92F6-0D9EAA2B39BB v4
Table 1079:ANSI Inverse time characteristics for Sensitive directional residual overcurrent and power protection
Function Range or value Accuracy
Operating characteristic:
( )
= + ×
-
æ ö
ç ÷
ç ÷
è ø
1
P
A
t B td
I
EQUATION1651 V1 EN-US
Reset characteristic:
EQUATION1652 V1 EN-US
I = I
measured
/I
set
0.05 ≤ k ≤ 2.00
1.5 x I
set
≤ I ≤ 20 x I
set
ANSI/IEEE C37.112 ,
±5.0% or ±160 ms
whichever is greater
ANSI Extremely Inverse A=28.2, B=0.1217, P=2.0 , tr=29.1
ANSI Very inverse A=19.61, B=0.491, P=2.0 , tr=21.6
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, tr=4.85
ANSI Long Time Extremely Inverse A=64.07, B=0.250, P=2.0, tr=30
ANSI Long Time Very Inverse A=28.55, B=0.712, P=2.0, tr=13.46
ANSI Long Time Inverse A=0.086, B=0.185, P=0.02, tr=4.6
Section 26 1MRK 502 066-UUS B
Inverse time characteristics
1390
Technical manual