ABB RELION 670 Series Technical Manual page 1394

Section 26
Inverse time characteristics
For RI and RD inverse time delay characteristics the possible delay time settings are instantaneous
and IEC constant time reset.
26.3 Inverse characteristics
Table 1076:ANSI Inverse time characteristics
Function
Operating characteristic:
æ
ç
=
t
(
ç
è
I
EQUATION1651 V1 EN-US
Reset characteristic:
t r
=
t
(
2
I
EQUATION1652 V1 EN-US
I = I
measured
ANSI Extremely Inverse
ANSI Very inverse
ANSI Normal Inverse
ANSI Moderately Inverse
ANSI Long Time Extremely Inverse
ANSI Long Time Very Inverse
ANSI Long Time Inverse
1388
When inverse time overcurrent characteristic is selected, the trip time of the stage
will be the sum of the inverse time delay and the set definite time delay. Thus, if
only the inverse time delay is required, it is important to set the definite time delay
for that stage to zero.
ö
A
÷
+ ×
B td
)
÷
P
- ø
1
×
td
)
-
1
/I
set
Range or value
0.05 ≤ td ≤ 999.00
1.5 x I ≤ I ≤ 20 x I
set set
A=28.2, B=0.1217, P=2.0 , tr=29.1
A=19.61, B=0.491, P=2.0 , tr=21.6
A=0.0086, B=0.0185, P=0.02, tr=0.46
A=0.0515, B=0.1140, P=0.02, tr=4.85
A=64.07, B=0.250, P=2.0, tr=30
A=28.55, B=0.712, P=2.0, tr=13.46
A=0.086, B=0.185, P=0.02, tr=4.6
1MRK 502 066-UUS B
GUID-F7AA2194-4D1C-4475-8853-C7D064912614 v4
IP15797-1 v2
M12388-1 v23
Accuracy
ANSI/IEEE C37.112 ,
±2.0% or ±40 ms
whichever is greater
Technical manual