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My house is 20 years old. All the proper locations are GFCI protected, but most do not have a GFCI outlet. They are connected downstream [I think that is the proper term], meaning if there is a short on the downstream outlet, the upstream GFCI trips to shut it down.

I was told by one inspector that you need GFCI outlets at every risky location because they trip ''faster'' than an outlet that is connected to it. Is this true?

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    Short answer: False – Tyson Dec 21 '17 at 18:13
  • Unless you have thousands of miles of wire between the GFCI unit and the downstream outlet (in which case voltage drop would make it pretty useless anyway), no. – CactusCake Dec 21 '17 at 18:23
  • @CactusCake actually the effect of miles of wire and voltage drop creates nussance tripping, safety wise it doesn't create a non-tripping issue. – Tyson Dec 21 '17 at 18:29
  • @Tyson I just meant you'd lose all your current to wire resistance and not be able to power appliances that far from the source. But yes, the GFCI does throw its own problems into the ring as well. – CactusCake Dec 21 '17 at 18:42
  • Is this a electrical code inspector or a real estate home inspector? – agentp Dec 21 '17 at 21:14
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"Inspector" is not too swift - I'd be tempted to run this up to the organization that certifies them as a qualified inspector, but I do like to make trouble sometimes.

They don't care at all about a short line to neutral - that's the circuit breaker's job. What they do is compare the current going on the line and the current coming on the neutral, and if they are not matched within 5 mA (number varies with part of world, but for the US) they trip - that happens when there's a fault (often far less than a full on short) to ground.

They work exactly as fast for remote or local connections, as they measure the current, and current changes instantaneously throughout a circuit with changes in load.

Some people even prefer GFCI breakers, which are all the way back at the panel. They work just as well.

  • Sadly there are MANY "home inspectors" that spread this particular piece of mis-information. Part of my day job is phone duty in an electrical contractors office, I have to give the "you do that really need to do that" speech about twice a week. – Tyson Dec 21 '17 at 18:55
  • Come on at the speed of light I am sure we could calculate the time delay difference something like -10 to the 18 power LOL. – Ed Beal Dec 21 '17 at 19:33
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    This inspector is clearly out of his element. I would recommend a call to his superior. – Paul Logan Dec 21 '17 at 19:40
  • @EdBeal: to be pedantic, electricity doesn't move at the speed of light, either charges or flow. closer to 1/8th the speed of light... – dandavis Dec 22 '17 at 6:10
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He's totally wrong

Your house is connected correctly. The inspector is completely wrong and he's been told that before, and he chose to huff out his chest and say "well I'm the inspector and that makes me right".... rather than have either the concern for work, or the sense of wonderment, to spend two minutes to learn the technology he is inspecting.

So yeah. Fire that guy. What he's really saying is "I want to see the buttons so I don't need to go out to the car to get my GFCI tester and then ask you where the reset is". This lunacy is also why the big box store sells GFCI receptacles in 10-packs.

...And serving regular receptacles downline from a GFCI device is correct. Not least, it protects the wiring behind the receptacle, which matters if you splash dirty water onto it.

But then...

In order to be legal, your downstream receptacles must have a "GFCI Protected" label. He would be correct to write you up for their absence.


Okay, there's one place where "faster" (as in lower threshold to trip) might make a scrap of sense, but only in Europe. There, they are fond of 30ma GFCI devices, often for whole-house protection (of the structure from ground fault related fires, not the people from shock). 30ma is too high a threshold for personnel protection - it can kill the weak, and knock anyone out cold, causing death by secondary effects such as drowning or falling. So yeah, if you're in Europe, and your downline GFCI device is 30ma not the proper 8ma, then okay. In the US, we use AFCI for fire protection, and most GFCI devices are about personnel protection.

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