tactic for finding "open ground" on circuit in a home?

[john70t]

I thought there were some better close-up pics but couldn't find em. They are at the rental.
Black/purple. I think the spatter is orange and yellow flecks. iirc

[masraum]

Thanks tons, I'll check with the missus. She's wanting to add some Art Deco touches to our place. I'm not sure if there's any place that she'd want these, but I'll find out and let you know.

[masraum]

Originally Posted by Zeke

GFCI's work just fine without a ground. You need to do some reading.

Got it. GFCIs protect an ungrounded circuit, but if you try to test them with a grounded tester, they don't trip which is supposed to be a positive result. On a grounded circuit, the tester works as expected.

[john70t]

I think the tester "test button" shorts hot to ground when pushed. If a ground isn't there it doesn't trip the GFI outlet.

An un-grounded GFI outlet still protects an overload surge from hot to neutral faster than the thermal spring breaker in the fusebox.

Ground is there to prevent a hidden short due to a hot wire touching the inside of a metal outlet/switch/the person flipping it.

[masraum]

Not doing any deep digging tonight, but checked the downstairs.

1 outlet shows hot/neutral reversed
1 outlet has romex with a ground going to it, but only has 2 prong plugs
1 switch didn't have a ground connected (fixed that, but still don't know what the switch does)
1 switch is a 3 way, but no idea what it does or where it goes.

The rest of the outlets show that they are wired correctly and the switches do something.

[rockfan4]

Originally Posted by masraum

1 switch is a 3 way, but no idea what it does or where it goes.

You didn't flip it, did you?

[masraum]

Upstairs
room 1, 2 outlets, both open ground (both show a ground wire under green screw)
room 2, 2 outlets, one open ground, the other good (ground wire under green screw)
room 3, 2 outlets, one open ground, the other good (ground wire under green screw)
room 4, 1 outlet that I can see, wired correctly

that's what I was afraid of. Everything LOOKS like it's wired correctly. Anyplace that there are multiple grounds connected, the twist looks tight and extensive.

I guess this is going to be a pain in the rear search. Maybe there's a problem in a box in the ceiling at a light somewhere.

[masraum]

Originally Posted by john70t

I think the tester "test button" shorts hot to ground when pushed. If a ground isn't attached it doesn't trip the GFI outlet.

An un-grounded GFI outlet still protects an overload surge from hot to neutral faster than the thermal spring breaker in the fusebox.

Ground is there to prevent a hidden short due to a hot wire touching the inside of a metal outlet/switch/the person flipping it.

I believe you're correct. If the ground isn't connected to anything, then shorting it won't flip the GFCI.

[masraum]

Originally Posted by rockfan4

You didn't flip it, did you?

ROFLMAO!

Oh no!

Any of you guys go a backhoe?

[Esel Mann]

Originally Posted by masraum

Got it. GFCIs protect an ungrounded circuit, but if you try to test them with a grounded tester, they don't trip which is supposed to be a positive result. On a grounded circuit, the tester works as expected.

Protecting (i use the term lightly) people from an ungrounded circuit was achieved by a circuit utilizing polarized (now standard) plug sockets properly wired. It was common practice for two prong circuits to wire the neutral to the enclosure of an appliance. With no polarized plug way back in the day, it was possible depending upon how one plugged it in that hot got connected to the intended neutral. For the appliance it functioned fine. But if you happened to touch the appliance and say for example a metal sink with metal plumbing, you got a nice wake me up. Was very common to get the wake me up with old skool microwave ovens or old skool whole house audio/intercom systems.

Presuming a properly wired and functioning gfci circuit, the gfci breaker/socket senses that the current from the hot side is flowing and matched with the current on the neutral side. It pops when that is not the case. The intent is to prevent a situation where the current instead of flowing through neutral, flows instead by way of ground. If said current is under the limit of a traditional hot side breaker, said breaker never trips. In places where there is moisture/wetness involved, for example, the by way of ground can be through a person. Well if the hot side breaker never trips....

[masraum]

Originally Posted by Esel Mann

Protecting (i use the term lightly) people from an ungrounded circuit was achieved by a circuit utilizing polarized (now standard) plug sockets properly wired. It was common practice for two prong circuits to wire the neutral to the enclosure of an appliance. With no polarized plug way back in the day, it was possible depending upon how one plugged it in that hot got connected to the intended neutral. For the appliance it functioned fine. But if you happened to touch the appliance and say for example a metal sink with metal plumbing, you got a nice wake me up. Was very common to get the wake me up with old skool microwave ovens or old skool whole house audio/intercom systems.

Presuming a properly wired and functioning gfci circuit, the gfci breaker/socket senses that the current from the hot side is flowing and matched with the current on the neutral side. It pops when that is not the case. The intent is to prevent a situation where the current instead of flowing through neutral, flows instead by way of ground. If said current is under the limit of a traditional hot side breaker, said breaker never trips. In places where there is moisture/wetness involved, for example, the by way of ground can be through a person. Well if the hot side breaker never trips....

Which is clearly what people mean when they describe someone as "really well grounded."

[carambola]

one or two story dwelling?

[masraum]

two stories