Ground fault interrupting system for hvac equipment

Abstract

A device and method are provided for interrupting power to a branch circuit and connected load. The device includes a first ground fault (GF) sensor for monitoring a first leakage current across line conductor(s) and grounding conductor of the branch, which ignores leakage current across the grounding conductor, and a second GF sensor for monitoring a second leakage current of the load from the line conductor(s), which takes into account leakage current across the grounding conductor. A processor(s) detects for a GF on the branch circuit based on the first leakage current monitored by the first GF sensor; detects for a GF at the load due to excessive leakage current based on the second leakage current and an allowable/acceptable amount of leakage current for the load; and controls an interruption of power to the branch circuit if the GF on the branch circuit or at the load is detected.