Comments by "ke6gwf - Ben Blackburn" (@ke6gwf) on "The GFCI/RCD: A Simple but Life-Saving Protector" video.

  1. To clarify a key point, all current flowing from the outlet will end up returning to the neutral wire at the power pole, whether through the proper path, or through your stupid butter knife poking self! If it flows through you, it will end up going to a water pipe, a safety ground circuit, wet concrete etc, but will end up back at the ground rod or pipe bonding wire, etc, and flow back to the main panel where the Neutral wire is Bonded to the Grounding system, and thus return to the neutral wire on the pole. Remember that all current requires a complete circuit in order to flow, so in order to have a ground fault, the electrons still need a path to return to the Source, be it the power plant, generator, solar panel, battery, etc. The soil doesn't magically soak electricity up, and it's a horribly high resistance if you try to use it as one side of the circuit to source. In fact, you can drive a long ground rod, and connect it directly to a 15 amp circuit breaker, and the breaker won't trip, because the resistance is so high very little current will flow, but what DOES flow is simply going to the nearest bonded ground rod to get back to the Source. The key purpose for ground rods is to bleed off static and lightning, and to reference the Neutral wire to be the same potential as the soil, water pipes etc. Think of standing barefoot on a metal plate, with a car battery sitting on the plate. If you touch either terminal of the battery, no current will flow, because there is no connection between the battery and the metal plate. If you now connect a wire from one terminal of the battery to the plate, that plate now carries the potential of that terminal, and is Bonded to it. Now if you touch the bonded terminal, nothing happens, because you are already at the same potential. And it doesn't matter if it's the positive or negative terminal bonded. That becomes the reference voltage. If you are getting power from a generator, you can bond either the hot or the neutral to the ground rod if you want, and that becomes the Earth Reference. So if you bonded the Hot to Earth, you can touch the hot wire while standing in the pool, and get no shock because they are the same potential. Sadly, if you touch the frame of the generator, you will die painfully, so don't ever do this! Lol This becomes important when dealing with transformers, because you have to pick which leg is bonded, what you want to reference to Earth. I was working in an industrial facility once, and in the evenings, the neutral wire would become 110v to ground, and the hot wire would be zero volts to ground. Then in the daytime it would be normal again. I started looking at the Big Picture™ (© 2018 HVACR Videos) and discovered that that mechanical room was being fed by a single 3 phase circuit to the main 3 phase panel on in it, and then there was a buck boost transformer feeding the 110/220v panel which ran all the lights and outlets etc. After some testing, I discovered there was an outside light with a photocell, that had a shorted out ballast, and that the electrician who installed the system had not bonded the center tap on the transformer to Earth ground, and so it was a floating system. So when the photocell turned on, it bonded one of the 110 v transformer legs to earth ground, driving the center tap neutral to 110v away from ground, and since the shorted out light was the only place the transformer was connected to ground, there was no fault current to trip a breaker....
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