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An ungrounded GFCI “Is Acceptable”. A GFCI does not need a ground wire in order to trip properly. A GFCI simply trips when a fault is detected on the neutral wire. Also, GFCI's can be used in place of ungrounded receptacles AND used for those ungrounded receptacles down line on the same branch circuit. All receptacles must be labeled GFCI protected AND ...


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Typically a patch panel would be grounded via its physical connection (screws) to a metal rack that would be part of a designed bonding and shielding system. Here is a great article on all the ways the ground path gets from the cable shield to the building's system. If you have a free-floating patch panel (eg mounted on piece of plywood) that comes with a ...


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Those earth bonding plugs are designed for use in ESD control, they contain a 1 megohm resistor which is desirable for ESD control purposes but makes them useless for shielding or safety earthing purposes. The only significant difference between British plugs and others is that they contain a fuse which provides better protection for the flex and/or allows ...


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Summing up and coloring in Here are several common failure scenarios and the behavior of various grounding configurations. A GFCI without a ground is much safer than a regular grounded outlet or an ungrounded one, and almost as safe as a grounded GFCI. Red is bad. Yellow is undesirable as it employs the user to trip the GFCI but it does so quickly and ...


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The return electrode needs to be electrically connected to whatever you are welding. Connecting it directly to the item being welded is best. If you connect it to the table, then the connection between the table and the item being welded would have to be good, and it usually isn't. The bit you have quoted specifically says that both clamps (you appear to be ...


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Interesting that this was migrated from the EE SE. I remediated this problem in my first house. It's very common. Two-prong outlets in an old house and some nitwit puts in three-prong sockets without a ground. The local authority (Ontario ESA in this case) says "No good, either ground it or put GFCIs on every socket" He also said I could put ...


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Do yourself a favor and install some kind of ground. There is no such thing as absolutely safe electricity. Any electricity is potentially unsafe, which means anything being safe in electrical systems is always relative to how you treat it. I went to school in a building that had open metal power lines running along the ceiling. That was considered ...


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This is exactly what the electricians did for a few outlets in my home. I had most of them grounded for the sake of the computers, but there were two or three where it was extra difficult to fish a ground wire and they installed ungrounded GFCI outlets. (House built circa 1951, this work done in 1995 or so.) Others have explained well why this works, and the ...


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#14 in 20A circuit #14 wire in the circuit will add a couple volts of voltage drop, but that isn't nearly enough to explain such dimming. Something else is wrong. You're always allowed to use bigger wire than is required, so #12 is perfectly welcome on a 15A circuit. In fact, it's particularly called for when you have a long run. So I see it as a 15A ...


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What are the exact differences between a no-ground GFCI outlet and a grounded GFCI outlet in terms of safety? Consider what happens when a wire comes loose inside an appliance and touches the case metal case. In the design of a "Class 1" appliance this would be considered a "single fault condition". If there is a proper ground connection ...


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Safer? Yes. Safe? No! Think for a minute and ask yourself "Why does the NEC require a sticker that says 'No Equipment Ground' if the receptacle is safe?". The key to this answer is your question asks about "appliances that expect a ground". The sticker is there to warn you to not use the receptacle where a ground is required. Here is the ...


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Yes! GFCI does not need a connection to Earth to work. If you put a GFCI in your main electrical panel, it measures the difference in current between Live and Neutral wires, and if that difference exceeds a threshold like 30mA, it will trip. The idea is, under normal conditions, all the current that flows from the power company's cable through the live wire ...


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I discovered that the wire to that 20 amp outlet was 14/2 If that's also on a 20A circuit breaker, you have a dangerous situation and you need to correct this ASAP! In fact you should shut this circuit off at the panel and leave it off until you replace the breaker with a 15A one or change the wiring to 12 ga. Scared now, knowing that the 14/2 would burn ...


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Safety In terms of safety, GFCI is all you need. The ruling factor for safety is that the GFCI will shut off if more than 5ma leaks (e.g. via a human being shocked). That is better human protection than grounding, actually. Lack of ground, however, reduces the chance of a shock happening (and thus a shock being detected). If a human touches hot and ground ...


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Absolutely! There are a number of different functions that an ordinary ground wire performs. A GFCI, despite the "G", does not actually need a ground wire to function. In fact, a properly installed GFCI will provide protection similar to (and actually in some ways better than) a regular ground. That doesn't mean you shouldn't have ground. But it ...


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Sounds like rather old work, but the 2" conduit is nice, since you can upgrade to anything you want. Metal conduit is a valid ground path. But underground, it tends to rust out. If the wires are still free-moving and pullable, I would pull in a #8 ground wire now, while it's still possible. Once the pipe rusts out, it ceases to be effective as a ...


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#4 or 1/2” rebar can be used as the concrete electrode 20’ is the minimum and you will need to stub it up or connect a #4 awg copper wire to it with an approved clamp usually if connecting to the rebar the wire in the concrete is required to be sleeved as it exits but then the connection is not required to be accessible, if connecting to a stub of rebar that ...


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Damaged skin reduces your body’s natural resistance so you felt the shock. This low voltage can be generated in many ways and at that low of a voltage is not dangerous. the National electric code article 411 low voltage lighting: think swimming pools hot tubs where this lighting is normally used allows 15 volts ac where wet contact is likely. I regularly ...


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No, this is not normal and dangerous. I suggest that you hire an electrician or least favorable option (ground is like crazy science to regular person and there are a lot of gotcha ya), do your own research. It looks like there is insufficient grounding and your heater or some other appliance has a ground fault. All of the electrical circuits and appliances ...


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