ABB Relion Technical Manual page 747

1MRK 502 048-UUS A
Technical manual
Table 576: RI and RD type inverse time characteristics
Function
RI type inverse characteristic
1
= ×
t td
0.236
-
0.339
I
EQUATION1656 V1 EN
I = I /I
measured set
RD type logarithmic inverse characteristic
æ ö
I
- ×
ç ÷
= 5.8 1.35 In
t
è ø
td
EQUATION1657 V1 EN
I = I /I
measured set
Table 577: Inverse time characteristics for overvoltage protection
Function
Type A curve:
td
=
t
æ ö
-
V VPickup
ç ÷
è ø
VPickup
EQUATION1661 V1 EN
V = V
measured
Type B curve:
×
td 480
=
t
æ
-
V VPickup
× -
ç
32 0.5
è
VPickup
EQUATION1662 V1 EN
Type C curve:
×
td 480
=
t
æ
-
V VPickup
× -
ç
32 0.5
è
VPickup
EQUATION1663 V1 EN
Time inverse characteristics
Range or value
td = (0.05-999) in steps of 0.01
td = (0.05-999) in steps of 0.01
Range or value
td = (0.05-1.10) in steps of
0.01
td = (0.05-1.10) in steps of
0.01
2.0
ö
-
÷
0.035
ø
td = (0.05-1.10) in steps of
0.01
3.0
ö
-
÷
0.035
ø
Section 21
Accuracy
Accuracy
±5% +60 ms
741