A couple electrical questions here. 1. Can you put more than one GFCI on a line. 2. My rental has a line hooked up to a outdoor switch which turns on a outlet further down the yard. When I turn on the switch the breaker pops. I changed the switch and also tried a new outlet and it still pops every time I turn it on the switch. What should I look at nexted. Thanks
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GFI works by measuring the flow of current down the hot versus the flow of current in the neutral. If somebody has miswired and is using the safety wire, green, as the neutral, white, you'll pop them every time.
Evetss,
Is the breaker in the panel popping, or is a GFCI doing so?
Different causes for different things.
SamT
A GFCI should have two sets of terminals... 'line' and 'load'. Power coming from the panel to the GFCI is wired to the 'line' terminals. A wire going downstream to another outlet(s) is wired from the GFCI 'load' terminals. The downstream outlet(s) is standard, not another GFCI.
Re switching a GFCI, it should work. In my experience, sometimes they don't like it. You can't have a GFCI fed the same power as a three-way switch... something about that arrangement trips the GFCI every time you move either switch. Is there anything on your rental switch aside from an outdoor outlet?
If the breaker trips when you turn the switch on, you're got something wired wrong.
I once saw a switch wired up so the hot was on one side and the neutral was on the other. When you turned it on, that provided a direct short, which obviously tripped the breaker.
But that was a long time ago, and I've conveniently forgotten who wired it up that way. (-:
so what does this bad wire guy (that you cant remember) have to do with this?
Why am I getting a deja vu feeling about the recent 3 way switch thread?
The two wire romex comes down the deck to a toggle switch. Another 2 wired romex goes from the switch to the outlet. The 2 neutrals (white) are twisted together in the switch box and the 2 hots (black) are on the toggle switch. When the switch is switched on the breaker in the breaker box trips. If I put an outlet where the switch is by attaching the hot and neutral from the 2 wire romex from the house, everything is fine . So the theory of the underground wire being the problem sounds right, but what could be going on with the underground wire that would make the breaker trip...if that is the problem... thanks again
Get yourself an ohmmeter or continuity checker.Turn off power to the circuit. Disconnect the underground cable -- both black and white wires -- on BOTH ends.Use the ohmmeter to check between the black and white wires on one end, then between each wire and the cable's ground wire. You should see no continuity on any of the measurements.Now twist the black and white wires together on the far end and measure continuity from the near end. You should read continuity.If you register a short, you have a slight chance of being able to guess where it is by measuring the resistance of the short from both ends. If the ohms scale on your meter is low enough, and if you're careful to make good connections with the meter probes, you may be able to measure a difference in resistance between the two ends. The lower the resistance, the closer you are to the short.Or just check it out with a TDR.
Evetss,
If you have also eliminated the far outlet as a possible, then the only thing left is the underground cable.
It is shorted, ie, the hot conductor is making contact with the conductor in the white insulation. The reason? Rodents. Shovels. Rocks. Age. Etc.,etc. Who cares why, it needs replaceing.
SamT
Sam , thanks for all your help.
"so what does this bad wire guy (that you cant remember) have to do with this?"
I thought maybe this guy had done the same thing that my "friend" had done.
(Ahem) Sure wish I could remember who that guy was...
If there is no wind, row. -- Latin Proverb
1. You can have more than one GFCI on a branch circuit, but you shouldn't use them in series. That is, you shouldn't "feed through" one GFCI to the next. (Actually, there's probably no hazard in doing this, but it's not good practice.) If necessary, make "pigtail" splices in the box with the first GFCI so that you can continue the circuit to the second without using the feed-through terminals.
Of course, the other, probably more reasonable option is to simply use the feed-throughs and eliminate the second GFCI.
2. You need to find the short. If it's a GFCI breaker that's popping the problem could be leakage from an underground splice, or neutral and ground erroneously tied together or swapped. An ohmmeter is your friend.
Thanks for the quick responses...these are (2) different question. The outlet on that line is just a regular outlet. Its the breaker in the box that trips everytime I try to turn on the switch. I did put an outlet where the switch is and that worked fine. So I'm thinking it must (but not always) be something between the switch and the outlet. The line does run under ground from the switch and the outlet. if that helps. thanks again. It is on a 20 amp breaker.
"I did put an outlet where the switch is and that worked fine. "
Switches and outlets aren't interchangeable. If you've removed an outlet and tried to put a switch in without re-wiring, that's your problem.
You can tune a guitar, but you can't tuna fish.
Had another thought after I posted that last time - If you removed an outlet and put in a switch, the switch likely has one white wire and one black one attached to it. Is that the case?
Hope is a waking dream. [Aristotle]
Let me see if I understand this.
You have a switch that pops the C/B everytime you turn on the switch.
The wire from the switch goes underground.
From most to least probable:The line that goes underground from the switch, or the switch, orthe outlet you think is powered by the switch,is no good.
To troubleshoot from cheep to expen$ive . . . If the outlet does not pop when you:Take the outlet off the wire = the outlet is badreplace the switch = the switch is badthe outlet pops when you do both = the wire is bad
My milkbone is on the wire.
By now, you have popped this Circuit Breaker too many times, they go bad pretty quick when popped too many times. Replace it after you fix the problem.
Evetts, it is obvious to us now, that you really don't understand a thing about house wiring and electricity. I realize that here at BT we have cumulatively, thousands of years of experience, but that is no substitue for having an experienced electrician on the site.
You are messing around with a system that can look like it works fine and still burn your house down or kill someone with even with something as subtle as a little change in the weather if it is not done correctly at every step.
Hire an electrician. In less than an hour, he could have wired your switches and lamps and discovered the popping C/B problem. Your home and life aren't worth the money.
SamT