Before using a portable welder without GFCI coverage, what grounding check is recommended?

• A. Checking continuity of the ground prong to the equipment case
• B. Verifying insulation resistance between live and neutral
• C. Visual inspection only
• D. Measuring voltage between phases

Answer: (A)

Grounding integrity is essential when a portable welder lacks GFCI protection. The key check is to verify that the grounding prong is continuous with the equipment’s metal case. This confirms the chassis is bonded to the earth through the ground conductor, giving a low-impedance path for any fault current. If a fault occurs, the current will flow to ground rather than through the operator, allowing protective devices to trip or the system to safely clear the fault.

If this bond is broken or the ground path is open, the case could become live, presenting a serious shock hazard since there’s no GFCI to detect a fault and trip.

Other tests don’t address this critical safety path: insulation resistance between live and neutral checks only insulation, not the grounding bond; visual inspection alone can miss a hidden fault; measuring voltage between phases isn’t about the grounding path.