DSP-OHMNI Instruction Manual I-GARD
19
Pressing
u
takes the user to the Screen 2 which shows the total system ground current IG as a percentage
of the maximum ground current allowed by the grounding Resistor. As a reference, the setting for the
Maximum Ground current is shown as IG max (5A in the example of Figure 7.2)
.
The IGmax current must
agree with that of the Neutral Grounding Resistor of the system. If it does not then the OHMNI-PM set-up
must be repeated.
IG SYSTEM A =10%
100%(IGmax) =05A
Figure 7.2 System leakage current l
G
NOTE
this screen can only be seen when the system does not have a fault as will be seen.
Press
u
again to view Screen 3 which is the Feeder Module screen in Figure 7.3 below. It allows the
user to examine the status of the installed DSP-DFM modules. Feeder Modules are identified by their I/D
numbers from 1 to 50 and may be scrolled through with the
pq
keys. Priority settings can be observed (
10
in this case) and Ground Current Igf for the Feeder is displayed as a percentage of the maximum Ground
Current of the System. A reading of ”
- -
“ would represent a direct short to ground for the Feeder while 00%
represents no current leakage at all. STATus is indicated as well which shows whether or not the Feeder
Module is
OK
(leakage below 50%),
FLT
(faulted) leakage greater than 50% or
TRP
(Tripped) which may
happen if a second fault caused current in the sensor to exceed 100A for 200mS or more.
FDR 01 PRIOR 10
1Gf 07% STAT OK
Figure 7.3. Feeder Current I
Gf
Only those DSP-DFM modules that have valid I/D settings will indicate successfully. All others will indicate
as though they were not installed with blank characters in the display fields.
NOTE:
to identify which DSP-DFM is which, if not sure, the user can push the I/D/TEST button on each DSP-DFM until the
Status indicator on the Feeder Screen shows ‘
TST
’. This will be the FM selected and the I/D can be read on this screen.
If the TRIP function was defeated in the Setup Mode, then the Feeder Modules that are disabled will
indicate with a screen similar to Figure 7.4
FDR 01 TRIP OFF!
1Gf 07% STAT OK
Figure 7.4 Trip Defeated
