House electrical question

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thelazyl

Well-known member
Joined
Nov 9, 2018
Posts
600
Location
Molalla, Oregon
Hi All,
I am an electrical novice and hope someone can give me advice.

My DW and I were able to move back into our sticks/bricks home after spending 12 days in the RV. We had an ice storm that caused significant damage to our power grid. 12 days ago we had a lot of "flicking" of power and smelled burned wires before the power finally went out. Talked to our electrician and concluded the smell came from our clothes dryer because of a voltage spike while the dryer was operating.

While the power was out I turned off breakers to our water heaters and also unplugged our hot tub which has worked flawlessly for 2 years. Today, when trying to start the hot tub back up, it immediately trips the outlet (ground fault?). It is a small 2 person hot tub that is plugged into a dedicated 25 amp circuit (110). I tried re-setting the outlet but it trips almost immediately when I turn on the hot tub pump.

I plan to call my electrician but would like your input.

I assume that something happened to the hot tub pump when we had power flicks? Is there a simple diagnostic I can try? I do have a volt meter but my only experience with it is watching a YouTube on how to test on an RV.

Thanks in advance!
Mark
 
This is just a guess, but I suspect something froze inside your hot tub, perhaps the heater, and it is now tripping on ground fault, though from time to time ground fault outlets do go bad.
 
There's no such thing as a 25A circuit, if its 120V it's probably 20A.

If the outlet is tripping, that's a ground fault event. As opposed to the circuit breaker in the house panel, which would be overcurrent. So it does appear you may have a ground fault though in light of unstable power the outlet itself may have gone wonky. The test would be to plug something else into the outlet and see if it still trips. Another test would be to plug the hot tub (via extension cord) into a different GFCI outlet and see if that one trips. By playing musical outlets you can isolate the issue to the outlet, or the tub.

I don't have a lot of experience with hot tubs but ones I've seen have a pump and a heater. So if the problem appears to be in the tub you can try and unplug one or the other and see if you can isolate the issue to the pump or heater itself.

Mark B.
Albuquerque, NM
 
Thank you for your replies. I just took a desk lamp out and it works OK without tripping the outlet. I also tried turning off/on the breaker and confirmed the tubs still trips the outlet. Based on this I will focus on the tub pump and heater. Much appreciated!
 
There's no such thing as a 25A circuit, if its 120V it's probably 20A
Not sure why you would make this claim.
25 amp GFCI circuit breakers are available.


What am I missing?

Don
 
The Lazyl

You haven't completed the second part of the test. Get an extension cord and see if the hot tub will run from a different outlet, preferrably another GFCI (bathroom maybe?)

A lamp is a poor choice to test a GFCI outlet because it doesn't have a ground, it's a two prong load. Do you have something that draws a bit more current and uses a three prong plug with a ground?
 
What am I missing?
That was a branch breaker.

In a home, you're will not find any 120 VAC outlets rated over 20 amps and most 120 VAC plugs are rated 15 amps max. But 30 amps is common to run a small RV like mine, but that is for the entire RV, not just a single outlet.

-Don- Auburn, CA
 
A lamp is a poor choice to test a GFCI outlet because it doesn't have a ground,
You can test it with a two prong light. A GFCI has nothing to do with the ground wire. You don't need a ground wire at all for a
gfci to work properly. It measures the current draw on the two wires and if there is a difference of over 5 millamps then the breaker trips.
 
Don't mess around - Get your electrician on-site.

You've reported a burning smell and you report a repeat breaker tripping.

A novice troubleshooting this on the internet is a really bad idea.

Make sure the electrician understands everything you did pre and post ice storm. Make sure all appliances and circuits are loaded while he is there. Make sure he and you are both comfortable any damage to wiring, circuits, circuit breakers and appliances - including hot tubs has been identified and corrected.
 
You don't need a ground wire at all for a
gfci to work properly.
I will clarify that . . . (IIRC, you were an electrician, so I realize you already know this stuff).

But for some others here who probably don't . .

You don't need a ground at the outlet for GFI to work properly.

But you do need a ground to make it trip! Where else will the current go to cause less current on the white than black AC wire?

Through a body is one possible path to ground! And that is what GFI is for. It often trips so fast you don't even feel it. That is around 20 milliseconds to trip.

But GFI or not, you can still be killed if you get across the outlet black and white. No ground required to kill a person, even with GFI!

GFI ONLY saves you from hot to a ground. GFI will NOT save you if you get across the white and black wires.

-Don- Auburn, CA
 
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Don that is completely wrong. The ground wire is totally unnecessary. The GFCI trips when the current exceeds 5 millamps. It can only do this if the amount of electricity is imbalanced because more than 5 milliamps goes to ground through some other path than the black and white wires, like your body. You will never feel a thing with a less than 5 milliamp shock. The scientist who created the concept proved it at a demonstration where he jumped into a bathtub full of water holding on to clock radio.

However the ground wire is still necessary because the National Electrical Code requires all outlets to be bonded.

Here is an article that explains it better than I can and it has a schematic diagram which shows that the ground wire has nothing to do with the circuit.


I recently bought a hair dryer and it is required that hair dryers now contain a GFCI molded into the plug, which is two wires only. If the ground wire was necessary then they would have had to use a three wire plug.
 
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Don that is completely wrong. The ground wire is totally unnecessary.
Isn't that exactly what I said? A ground wire at the outlet is totally unnecessary for it to trip. But a ground PATH is 100% necessary for it to trip open and stop the AC output.

A two wire outlet can have GFI where there is no ground (green) wire.

And it is not always at 5MA. They are not that accurate. But newer ones are usually faster than older GFIs. Perhaps a new one will trip at a 5 ma difference between white and black.

-Don- Auburn, CA
 
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The test button on a GFCI outlet will not work if the ground wire isn't hooked up but the outlet will still function and protect you. When you push the test button it sends current through a resistor to ground to create the unbalance needed for the unit to trip.
 
The test button on a GFCI outlet will not work if the ground wire isn't hooked up but the outlet will still function and protect you. When you push the test button it sends current through a resistor to ground to create the unbalance needed for the unit to trip.
Yep, there MUST be a path to ground for GFI to trip, but no ground is needed at the outlet for GFI to work.

I think that confuses some people.

The entire purpose of GFI is in case you get between hot and ground. Such as a real dirt wet ground.

That is why outside outlets have GFI, as well as kitchens, bathroom, but usually NOT wall outlets inside of a house where no water is expected and there are no wet (or dry) dirt grounds. And no water pipes nearby, which are grounded.

-Don- Auburn, CA
 
Great feedback all! This is what I plan to do:
1. I will call the electrician to inspect.
2. I will open the side of the hot tub and look for excess water and/or a broken pipe

I will report back when I find out what happened!
 
No, there is no need for a path to ground. You become the path to ground if there is a current leak and that is why it trips. All the current that was sent out does not return because of a leak. You won't feel a 5 mA or less but above 5 mA the GFCI trips.
 
No, there is no need for a path to ground. You become the path to ground if there is a current leak and that is why it trips. All the current that was sent out does not return because of a leak. You won't feel a 5 mA or less but above 5 mA the GFCI trips.
Current has to add up to exactly the same as you start with. It is impossible to make the total current decrease in a series circuit. So if you start with 1.23456789 amps, you end with EXACTLY 1.23456789 amps regardless if the total return is on a single wire or a billion wires. Or from ground. The total current is ALWAYS the same as you start with anywhere in a series circuit.

After the trip, you now have no current to start with as there is then there is an open at the black. Between you and the black that is. Going to the outlet is still hot, just nothing coming out after the trip and it then has no current. That is what saves people.

If you lose 5ma at the white wire it is because it is because 5ma is going to the green or ground and returns to the black as the FULL total current until the trip.

-Don- Auburn, CA
 
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