I-Gard DSP-OHMNI, Manual

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safely isolated and removed.
If pulsing is selected ON, then it will remain ON until turned OFF again or RESET is pressed. The home screen has a
Pulse signal indicator to remind the operator that pulsing is ON with the screen of Figure 26.
Figure 26: New Home Screen indicates Pulsing ON
12V DC Pulse current is sent from the DSP-DPS ‘+’ and ‘-’ terminals to the DSP-OHMNI-PM neutral grounding resis-
tor to energize the solid-state relay in the OHMNI-PM to modulate the ground fault current (if any). When finished with
the pulse operation, press the home button to exit and return to the home screen.
Alarm Indications
If a fault greater than the alarm level setting develops somewhere on the system, or the (optional) DSP-DRM resistor
monitor detects a neutral grounding resistor failure, an alarm is declared by the system module. Alarms are annunci-
ated in three ways:
1. LED Indications
- DSP-DSM system module red ALARM light
- DSP-DFM fault indication is enabled to provide indication if fault is detected by feeder module (the fault may
not be detected by a feeder module. For example, if it is on the main bus it won't be detected).
2. Alarms
DSP-DRM red light (NGR FAULT) lights.
Alarm relay (Form C) on DSP-DPS will operate to energize customers’ alarm device (horn etc.)
A local beeper will sound in the DSP-TDM to indicate the fault.
The alarms both local and external can be cancelled by the MUTE button, which is the key on the Home
screen. Once cancelled, the alarm will remain off until the MUTE Delay times out from the moment of the last initia-
tion of the MUTE command, and if an alarm condition still exists. RESET will also cancel the MUTE effect. The MUTE
control of the alarm relay contacts may be disabled to allow use of the ALARM contacts in the DSP-DPS power supply
to be used for other purposes than an audible horn (fans for example). However, the MUTE in that case would still
silence the local beeper.