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ceiling fan install questions.

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Jun 06, 2013, 11:04 PM
krazykb78
ceiling fan install questions.
Installed a new ceiling tonite in my sons bedroom. It is controlled by switch , 1 for fan & 1 for light. This bedroom is on its own circuit with adjoing bedroom (panel says bedroom 1-2 on this breaker). I wired black to black , white to white , red to blue , bare to green. Turned breaker back on and fan/light worked as it should. Well about an hour later went into master bedroom (it to is on its own circuit) and no lights. Went to panel and breaker was tripped . Flippd it back on and about 2 hours later it tripped again. So kinda puzzled as to why the master bedroom is tripping but not bedroom #1 where the fan was just installed. Its a newer home built in 09 , there was not a light or fan fixture installed previously in bedroom #1. The circuit breaker in panel is one that has a test button and three different postions (I think middle postion was ground fault) . I've just moved into home a few weeks ago and haven't had a problem with tripping breaker until tonite so any advice is appreciated. Thank you
Jun 07, 2013, 07:11 AM
Jaybee
First, I just want to confirm that when the circuit breaker for the master bedroom trips that it also kills power to the fan. If so, then:

Electric motors and GFCI breakers do not like each other. While not always the case, I've seen many GFCI circuits that are so sensitive that adding in a motor (ceiling fan, bath vent fan etc) will cause the GFCI to trip. The bad news is that it's not always an easy fix - you have to isolate the fan from the GFCI circuit. That means finding another circuit as a power source for the ceiling fan.


Jaybee
Jun 07, 2013, 07:57 AM
krazykb78
No it doesn't kill power to the fan I installed because that fan is on a seperate circuit. The master bedroom circuit is the one that is tripping. I do have a ceiling fan in master bedroom and it was on when circuit kept tripping, but it never did this before I installed new ceiling fan in bedroom 1 .
Jun 07, 2013, 11:10 AM
swschrad
there is such a thing as a common neutral between two hots on different phases of the 240v home service, it's called an Edison circuit. it's more common than a lot of folks realize.

and if the fan is on the black wire side using phase 1, and the bedroom is on the red wire side or phase 2, you have an inductive "lead" of current phase on the neutral.

this looks to a GFI like current from who-knows-where, but it sure as heck didn't come from THIS black lead. so... SNAP.

I learned the hard way wiring the hot tub that this doesn't work, and then figured out why. it's not necessarily public knowledge that excessive capacitance across a circuit (like wire insulation, for instance) lags the waveform, thus the current, of a circuit. inductance leads the waveform, or shifts it right if you are looking on a scope. but it's transmission line calculus (phase angle is the usual term) and the reason telephone companies put load coils on their wires every 6000 feet. the reason power companies put big banks of capacitors under 3600 volt lines when inductive loads change the power factor and heat the lines.

a GFI has a chip that compares current in the black to current in the white, and if there is a 5 mA difference, it thinks there is leakage to a false ground, and trips in case that leakage is going through a body.

in your case, the fans have to be run on something other than a GFI circuit. this is why I can't stand GFI breakers (freaking dictators!), which will get false trips sooner or later, and put GFI outlets where needed, one by one. I can control and isolate faults to the spot where they occur, rather than "way out there someplace, gimme another beer, I've had enough of this."

This message has been edited. Last edited by: swschrad,


sig: if this is a new economy, how come they still want my old-fashioned money?
Jun 07, 2013, 12:48 PM
krazykb78
Ok so I should confirm how master bedroom fan is wired and wire fan in bedroom 1 the same way ? Or replace gfi breaker ?
Jun 07, 2013, 02:02 PM
swschrad
I would identify the outlets on the GFI breaker that need protection, and get the corresponding number of GFI outlets to replace the standards. then I would replace the GFI breaker with a standard one. as soon as I know the breaker works, I would shut it off and replace those outlets that need GFI protection before turning on that breaker again.

anything really stupid like a hot tub motor or heater, or a garbage disposer, that requires a GFI and is usually installed with one of those breakers is supposed to be on its own circuit anyway. so unless there have been, ahhhh, incorrect device additions, this should only affect a number of low-watt usages.

now, if you have an arc-fault breaker, you have another situation. neither arc-fault, which has no at-usage equivalent, or GFI breakers are going to please anybody on an Edison circuit.

I assume you know that DANGER, WARNING, FATTENING, ETC. raw power runs wild inside entrance panels, and unless you know exactly what you are doing and where you must not go, opening a panel is best left to a professional electrician. some communities require a permit.


sig: if this is a new economy, how come they still want my old-fashioned money?
Jun 07, 2013, 03:36 PM
CommonwealthSparky
quote:
Originally posted by swschrad:
there is such a thing as a common neutral between two hots on different phases of the 240v home service, it's called an Edison circuit. it's more common than a lot of folks realize.

and if the fan is on the black wire side using phase 1, and the bedroom is on the red wire side or phase 2, you have an inductive "lead" of current phase on the neutral.

this looks to a GFI like current from who-knows-where, but it sure as heck didn't come from THIS black lead. so... SNAP.

I learned the hard way wiring the hot tub that this doesn't work, and then figured out why. it's not necessarily public knowledge that excessive capacitance across a circuit (like wire insulation, for instance) lags the waveform, thus the current, of a circuit. inductance leads the waveform, or shifts it right if you are looking on a scope. but it's transmission line calculus (phase angle is the usual term) and the reason telephone companies put load coils on their wires every 6000 feet. the reason power companies put big banks of capacitors under 3600 volt lines when inductive loads change the power factor and heat the lines.

a GFI has a chip that compares current in the black to current in the white, and if there is a 5 mA difference, it thinks there is leakage to a false ground, and trips in case that leakage is going through a body.

in your case, the fans have to be run on something other than a GFI circuit. this is why I can't stand GFI breakers (freaking dictators!), which will get false trips sooner or later, and put GFI outlets where needed, one by one. I can control and isolate faults to the spot where they occur, rather than "way out there someplace, gimme another beer, I've had enough of this."

Please explain this Edison circuit that you speak of. Something that I am not sure of or seen in place, that I can tell. And why it would bare in the case. {I hunger for knowledge.} Big Grin Is not this every single phase 240v residential service in America? I know of no other.
Plus it is common to split legs on 240v circuits, very hard not to considering the breaker that is needed in this application. As this set up will safely split a heavy current draw between those two hot legs. And this feature is paramount in safe electrical theory.

This message has been edited. Last edited by: CommonwealthSparky,


Popeye only reached for the Spinach can as a last resort...
Jun 07, 2013, 03:48 PM
CommonwealthSparky
quote:
Originally posted by Jaybee:
First, I just want to confirm that when the circuit breaker for the master bedroom trips that it also kills power to the fan. If so, then:

Electric motors and GFCI breakers do not like each other. While not always the case, I've seen many GFCI circuits that are so sensitive that adding in a motor (ceiling fan, bath vent fan etc) will cause the GFCI to trip. The bad news is that it's not always an easy fix - you have to isolate the fan from the GFCI circuit. That means finding another circuit as a power source for the ceiling fan.

I agree with what is posted 100%. One wonders aloud why a bedroom is on a GFCI breaker to begin with. But we all know the world of previous electrical work having no rhyme or reason. I too think "leakage" is the culprit. And running to the load center every false trip for a reset breaker is a royal pain. {Newer breakers and outlets have much cleaner specs resulting in fewer false trips.}
I too would search for another circuit in the load center to place the fixture on. Or replace the breaker. According to the NEC since you are performing an upgrade this circuit has to be a AFCI breaker protected. But that is truly splitting hairs here. And it may be a debatable point mainly because of the amount of new work performed. {Very little.} I personally would fly with a standard breaker unless an inspector would insist on the more expensive AFCI breaker.
Assuming of course you have the skill and ability to do your own electrical work. Be careful and good luck.

This message has been edited. Last edited by: CommonwealthSparky,


Popeye only reached for the Spinach can as a last resort...
Jun 07, 2013, 04:10 PM
krazykb78
after a little further inspection of panel the breakers installed on both bedroom circuits are afci breakers.
Jun 07, 2013, 08:49 PM
CommonwealthSparky
So your fan may be arcing and creating a false trip. I really see that in remodel work if your install an AFCI breaker and the the finish carpenter wants to trim out a room. Problems abound. But I have never be to a job to witness a fan/light trip a breaker.
Is the fan/light or the AFCI breaker the culprit? Good question. Or is one of the outlets on the circuit the culprit? Leakage across old outlets will also cause a AFCI to false trip as well. Just a guess on that one, but has been known to be a cause. Google AFCI trouble shooting and you will find that reply.
Got to do some serious head scratchin on this one, back later with a reply. As their should be no reason why a circuit unrelated to your fixture install is affected. That makes me wonder aloud.

This message has been edited. Last edited by: CommonwealthSparky,


Popeye only reached for the Spinach can as a last resort...
Jun 07, 2013, 09:18 PM
krazykb78
I have had both fans and lights on and running for about 6 hours tonite with no issues , so I dont know either.
Jun 08, 2013, 07:32 AM
CommonwealthSparky
I also think that if a problem does pop up recheck the connections made in the the fan/light. As the stranded and solid wires may not have been the best connection possible. But boy oh boy is that a reach, welcome to the world of trouble shooting. A poorly made up connection could arc and result in a breaker trip. This could be the reason mainly because things did work correctly before the fan/light install. But you never know.

This message has been edited. Last edited by: CommonwealthSparky,


Popeye only reached for the Spinach can as a last resort...