How fast will a QO GFI and HOM GFI trip on ground fault?
Product Line:
Circuit Breakers
Resolution:
These QO-GFI and HOM-GFI breakers are tested per UL943, and are rated to be applied on 60 Hz systems. Based on the UL standard, if there is a ground fault current in the range of 6 mA to 264 mA, the time to trip for the GFI to trip is specified by this formula: T = (20/I)^1.43, where T is the trip time in seconds, and I is the current in milliamps. Note that it is ok for the breaker to trip faster than the formula. As a reference, attached is a chart showing the UL trip time at 6 mA and at 264 mA. The chart can be downloaded and other values between 6 and 264 can be entered into the cells.
Circuit Breakers
Resolution:
These QO-GFI and HOM-GFI breakers are tested per UL943, and are rated to be applied on 60 Hz systems. Based on the UL standard, if there is a ground fault current in the range of 6 mA to 264 mA, the time to trip for the GFI to trip is specified by this formula: T = (20/I)^1.43, where T is the trip time in seconds, and I is the current in milliamps. Note that it is ok for the breaker to trip faster than the formula. As a reference, attached is a chart showing the UL trip time at 6 mA and at 264 mA. The chart can be downloaded and other values between 6 and 264 can be entered into the cells.
Released for: Schneider Electric Canada
