Effective 11/2003
Page 13
I.L. 66A7535H02
Ground (Earth)
Fault
Sensing Method
Breaker Secondary
Contacts Req’d
Figure
Reference
Digitrip GF
Sensing
Element
Used
Residual
No Jumper
2.1
element R5
Zero Sequence
Jumper B6 to B7
2.2
element R4
2.3.4 Ground Fault Settings
The adjustment of the ground fault functional settings
(FLAT response or I
2
t) is discussed in Section 4.8. The
effect of these settings is illustrated in the ground fault
time-current curve referenced in Section 9. The residual
ground fault pick-up settings are from 0.24x to 1.00x (in
steps of 0.01) and OFF for the Digitrip 1150V and 0.10x to
1.00x for the Digitrip 1150V
i
. The settings below 0.24x will
require the Digitrip 1150V
i
to have auxiliary power to insure
proper tripping at these lower level ground fault currents.
CAUTION
IF THE PHASE CONNECTIONS ARE INCORRECT, A
NUISANCE TRIP MAY OCCUR. ALWAYS OBSERVE
THE POLARITY MARKINGS ON THE INSTALLATION
DRAWINGS. TO INSURE CORRECT GROUND FAULT
EQUIPMENT PERFORMANCE, CONDUCT FIELD TESTS
TO INSURE PROPER GROUND FAULT FUNCTIONAL-
ITY.
Table 2.1 Digitrip Sensing Modes
Figure 2.2A - Zero Sequence Current Sensor
