The I-Gard GADD MKIII is a modular Ground Alarm Indicator unit designed specifically for Ground Fault Indication and location, on Wye or Delta-connected, three-phase, three-wire, Ungrounded or High Resistance Grounded power systems. It may be used on systems up to any voltage with the use of 120V or 240V PTs.

An I-Gard Alarm Resistor unit (DDR2) is used to provide the GADD MKIII with a means to monitor the power system voltages to ground. This information is utilized by the GADD MKIII to determine and confirm whether a ground fault exists somewhere in the distribution system. This same information is also used to detect the occurrence of blown fuses that protect the phase lines connected to the Alarm Resistor unit itself.

Alarm on first fault at 50% of fault current

Phase and fault magnitude indication

Blown fuse indication

Available for 120V, 240V, 480V and 600V systems