27
3. Display
The home screen will change to an alarm screen that indicates which phase is faulted, and the branch circuit that is
affected. See Figure 27 for example.
Figure 27: Alarm Screen
The faulted feeder is identified by I/D number and name. The total system current IG will indicate the system cur
-
rent as determined by the voltage from the DDR2 voltage sensor unit . Note this may not be exactly the same as the
feeder current IGf that is indicated in the feeder module screen since the sum of all leakages will not necessarily be
the same as that of one particular feeder branch. Feeder fault information can be determined by pressing “System
Status”
▸
Feeder Module Statuses to move to the feeder screen. The faulted feeder (if any) can be located by scroll-
ing to the faulted one.
The current reading Igf relating to that feeder is shown. It should exceed 50%. The FLT status will also confirm that
this is the faulted circuit. In addition, there will be an alarm Indication on the faulted feeder module which is indicated
by a continuous red LED.
In the case of TRIP on first-fault, the LED indicator light on the DSP-DFM (feeder module) will be flashing. When the
system is faulted, it is necessary to determine the source of the fault. In some cases this might be known a problem,
but if the fault is not quickly identified, then the risk is that a second fault may develop and cause shutdown of one of
the breakers. To easily locate the fault, the pulse feature can be activated from the PULSE CONTACTOR SETTINGS
page if the partial ground fault current is not above the alarm threshold; or if is above the threshold an “Activate Puls-
ing” button will appear on the home screen.
If no feeder faults are identified, the display module will indicate BUS FAULT as in Figure 26 to indicate this unique
situation. In this case, the probability is that there is a fault upstream of the current sensors and usually indicates a
fault in the main transformer or bus duct which supplies the switchgear.
Summary of Contents for DSP-OHMNI
Page 1: ...C EG30EM Instruction Manual V2 June 2020 DSP OHMNI ...
Page 11: ...9 Figure 1b DSP DCM Wiring Figure 1c System Module DSP DSM Wiring ...
Page 12: ...10 Figure 1d Power Supply DSP DPS Wiring Figure 2 Preferred Feeder Module DSP DFM Wiring ...
Page 45: ...43 Figure 41 DSP DPS System Module Connection ...
Page 46: ...44 Figure 43 DSP DLM Logging Module Connections Figure 44 DSP TDM Display Module Connections ...
Page 47: ...45 Figure 45 Typical DSP DRM Installation Connections ...
Page 50: ...www i gard com Phone 905 673 1553 Toll Free 1 888 737 4787 Fax 905 673 8472 sales i gard com ...
