> Do you mean that ground fault interrupters are not fast enough/threshold currents too high to prevent harm in some cases? There’s some over generalization an

> Do you mean that ground fault interrupters are not fast enough/threshold currents too high to prevent harm in some cases? There’s some over generalization and outright misinformation in this thread. The required threshold for a Type A GFCI (aka normal residential) is 6mA in the US. GFCI breakers or outlets just need “another path” for the electricity to flow to trigger. Water / grounding / etc are not required, it could be a largish capacitor recharging. The way GFCIs work is by detecting a current imbalance between the positive and neutral wires. Electricity flows in a loop, so if more current is going out on the positive wire than what’s returning on the neutral wire, then it has to be going somewhere which could be bad if say it’s a hairdryer in the bathtub, but very much might be fine in the case of a VFD used with a spindle on a hobby CNC.