Utility Relay Company AC-PRO-II, Instruction Manual

Page: 43 / 56

AC-PRO-II
®
Instruction Manual www.utilityrelay.com
Page 41
Current in Percent of CT Rating
100% 20%
.01
40% 60%
GF I T OFF 0.10 sec
2
GF I
T
ON
T Slope 2
.10s
I
.10sec
2
200%
Ground Fault (GF) Pick-Up
20% GF
OFF & 10A steps
20% to 200% of CT Rating
100% 20% 40%
Pick-Up
200%
1000
(1A steps for CTs < 225A)
60%
S
E
C
O
NDS
.20sec
I
.30sec
with or
.1
GF Delay
.5
1
.40s
10
.20s
100
.30s
.50s
.40sec
.50sec
T
2
Pick-Up
200% GF
.50sec
GF ends
CT Secondary Rating 0.5A and above
1200A Max
50% to 200% of CT Rating
CT Secondary Rating below 0.5A
1200A only
CT ratios over 24000
(requires VDM or 24VDC)
at 12xCT
does not comply with
0.5 sec GF delay setting
IEEE C37.17.
Note:
.10sec
.20sec
.30sec
.40sec
.50sec
AC-PRO-II G.F. Rev 2.0 12/21/2016
Current in Multiples of Ground Fault Pick-Up
2X
.01
1X 6X 4X 10X
.1
.5
S
E
C
O
NDS
1
10
100
2X
1000
1X 6X 4X 10X
AND
I T Ground Fault Slope
2
Ground Fault Slope OFF
I T Ground Fault Slope
5
at 12xCT
GF ends
T Slope GF I
5
slope OFF
does not comply with
0.5 sec GF delay setting
IEEE C37.17.
Note:
(available for breakers
with 1-Amp CTs).
Figure 18.2: Ground Fault (GF) TCC