thumperstain

If I turn the ceiling fan on in my upstairs bedroom, the breaker for the dining room trips. The ceiling fan stays on. It has dimmable lights and I've determined that if I dim them to a lower level, no tripping occurs. Or if I turn on the fan only, no issues. Another ceiling fan in the dining room will cause the circuit for the electrical outlets to trip. The ceiling fan and the outlets are on different circuits. Why does it trip a totally different breaker?


Other Info -
I have a reef tank in my dining room. I upgraded the lights from 216 watts to 516 watts and the issue started occurring. There are two circuits in the dining room, one for the lights and one for the electrical outlets. The total draw of the tank equipment is about 900 watts. I have one lamp connected to the same circuit, but it's never on and hasn't been on at the time of the breaker tripping.

The dining room electrical outlet circuit has a 20A breaker.

House was built in 2010. I'm guessing this is related to something with AFCI, but I'm not sure whether explains the tripping of a breaker in a different room.

I have 3 other ceiling fans in the house. One in each of the other bedrooms and one in the living room. None of these will cause any breakers to trip, even when on at the same time. The main difference between these fans and the one in the bedroom / one in the dining room, is that the other 3 fans all use CFL lights with lower wattage requirements.

I've considered switching the lights in the two fans to CFL, but didn't want to do so until I understood this phenomenon and was sure it isn't indicating some sort of wiring fault.

Thanks for your time.

nealtw

New home warrentee???

thumperstain

Had one, but it was for 2 years. And apparently my house was built in 2009, not 2010. I'm getting old.

nealtw

Do any of the fans or lights have three way switches, as two switches for one light and have you changed anything to do with any of these cercuits?

thumperstain

No, neither of them have 3 way switches. I have 3 way switches in a separate room, so I understand what you're describing.

The only electrical change in the either room, was the changing of a chandelier in the dining room for a ceiling fan. I did that about 6 months ago. No tripping associated with that fan until the new lights. Other than that, I've changed a few rocker switches for programmable switches like http://www.amazon.com/Honeywell-RPLS530A-7-Day-Programmable-Switch/dp/B004SOZHR0/ref=sr_1_9?ie=UTF8&qid=1331071425&sr=8-9. All of the switch changes are in other rooms, on different circuits according to the breaker box.

It's probably not important, but both ceiling fans have remotes. The one in the bedroom has a dimmer, but the one in the dining room does not.

nealtw

I was just looking for the easy answer. You must have something crossed up somewhere, I can't imagine how that could happen. If you have two circuits feeding one fixture, your lucky it isn't 240 volts, but that would have been discovered right away. My guess would be you will have to start open boxes and disconnecting things so you can map all the circuits and locate the problem.
Unless someone comes along with a better suggestion.

thumperstain

I was afraid you'd say that. I'll give it a shot and if I find the solution (and survive) I'll post an update. One thing I noticed when searching the web for hours is that even if you're lucky enough to find a situation like yours, 90% of the time the thread drops off before the problem is solved and you're still left guessing.

Thanks for taking the time to help.

nealtw

If they wired with 3wire, black red and white. The red and the black each have there own breaker. If someone connected them together, you might get what you have. In the first box this goes to, the red should be attached to a black and nothing else. Or two blacks if the red is being used in that fixture.

nospmahm

I agree with nealtw, too bad Thumperstein did not come back to this site, after a month, and post his results!

thumperstain

I just needed a reminder...

Before I started playing with wires and mapping things out, I did what I usually do when confronted by a task I'm not eager to do and stalled. I had found a few links on the web, buried in the 5th or 6th pages of results on Google that had some similar issues to what I was experiencing.

The first - - http://www.forum.digitalaquatics.com/viewtopic.php?f=4&t=8119 . Mentions breakers tripping and a host of other issues caused by line noise from metal halide lights, what I installed and seemed to cause the problem. I tried putting a line filter between the lights and the circuit, but no dice...problem persists.

The second - http://forums.finehomebuilding.com/breaktime/energy-heating-insulation/afci-tripping-load-other-circuit is actually more relevant. It mentions the exact problem I'm having and if you read further on, you'll see advice similar to what nealtw provided.

The second thread made me curious. It describes afci circuits being tripped by loads on other circuits, and then at some point its suggested that maybe the issue is related to specific types of circuits. So before I started mapping things out, I figured I'd take my outdoor extension cord and do some tests. Basically I wanted to narrow down the different circuits within the house that would cause the trip AND see if there was any correlation between circuit types and the ability to cause a trip. So I went through the house, plugging the lights into other circuits and seeing if they could be tripped. I even would run a vacuum cleaner on neighboring circuits, as along with ceiling fan motors it seems to be the most commonly cited source of AFCI trips.

No matter what circuit I tried, I couldn't get the breaker to trip with the lights plugged in. This would seem to confirm the issue is with the original circuit. By this time it was late in the evening, and I decided I'd start mapping things out in the morning when I was fresh and had natural light to see. Rather than face my wife's wrath, I plugged the lights back into the original circuit so the cord clutter would be hidden. When I called up to her to let her know the test was done, she thought I was asking her to flip the ceiling fan upstairs on and so she did it. Nothing happened, no trip.

I was baffled. I went upstairs and did it myself. No trip. I went downstairs and turned the ceiling fan in the dining room on, no trip. I turned them both on. No trip. We turned them both on at the same time. No trip.

The lights are plugged into the same outlet, via the same cords and same spot in the surge protector. Nothing has changed, but I haven't had a trip in the last 5 weeks. I even have a single halide light that I occasionally run on a quarantine tank (don't ask, those of us with aquariums never have just 1 or 2), on the same circuit. It doesn't cause a problem either, even when turned on at close to the same time.

I delayed posting the findings because I expected this to be a brief respite, but the condition no longer exists. Then I forgot until the reminder that a new post was in this thread.