3 ms·
Do you absolutely 100% trust the GFCI breaker? They do require a small imbalance to trip, so something bad could happen in that brief time. Or maybe stopped w
by keenerd 14y ago
Do you absolutely 100% trust the GFCI breaker? They do require a small imbalance to trip, so something bad could happen in that brief time. Or maybe stopped working one day.
But technically yes, ungrounded GFCI will still protect you. Doing it intentionally is a bit like not buckling up because you have 100% faith in your air bags.
For the non electrical people: GFCI works by measuring the current in vs the current out. Normally these should be perfectly equal. But if you drop your hairdryer in the bathtub, maybe 10 amps comes in (through the plug), 9.9 amps goes out (through the plug) and 0.1 amps goes out (through the bathtub, killing you). GFCI notices that 10 != 9.9 and shuts down. The trick is detecting 0.01% differences and shutting it down in milliseconds, fast enough to save someone's life.
GCFI is way more complicated than a ground wire, and you'd be a fool to not have a cheap, passive and redundant safety system.
- ars 14y agoActually, it's totally legal. If you have an outlet without a ground wire, you can use a three prong GFCI and put a sticker on it that says "No Equipment Ground" and it's totally legal and to code. You are over exaggerating how useful the ground is - a GFCI is far more effective, the ground pin hardly does anything at all.
- keenerd 14y agoWhile I never said it was not legal (though I may have implied as such considering seat belt laws), code does require properly grounded outlets in bathrooms and other high risk areas.
- jrockway 14y agoOr maybe stopped working one day. I believe this is why they are labeled "test monthly". This is a lot more frequently than I check that neutral is not accidentally wired to hot or that the ground wire actually goes to the ground and not some random piece of plumbing that was removed in a renovation. (I live in a building that was built in the 1860s, and plumbing and wiring are being redone all the time.)