Digital ground fault detector for ungrounded, low-resistance systems


This device meets or exceeds the requirements of NEC 250.21(B) and CEC 10-106(2) for ground detectors in ungrounded AC systems, as well as the upcoming 2014 requirement of NEC 250.167(A) for ungrounded DC systems.

The isoLR275 detects ground faults in ungrounded, low resistance systems up to 793 VAC / 1100 VDC. The iso-PV monitors for ground faults by measuring the system's insulation resistance, providing early indication of ground faults before leakage current may even be present. Both AC and DC ground faults can be detected, including on systems that have high leakage capacitances.

The isoLR275 is specifically designed for ungrounded systems which run at a low resistance to ground. Included are two components, the ground detector and the high voltage coupler. Both are required for operation (the voltage coupler may be installed in a separate cabinet to keep high voltage connections separate).

The isoLR275 features a digital display which shows the system's insulation resistance in real-time. Two SPDT contacts are available. The isoLR275 utilizes an external supply voltage for power.

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