Ok heres my problem. This room has 4 floodlight fixtures for lighting. Instead of burning out like normal bulbs, these ones "flash out" when I flip the switch on. That's all fine and dandy, except that it trips the circuit breaker everytime. I'm 3 for 3 on them going like this, pissed off is an understatement.
Any idea what could be wrong? Is it the breaker? the switch? the fixtures? We're having an electrician come sometime in the future to work on something else, but I'd prefer to get some leads on this if I can, since there is only 1 more original bulb (that came with the house when we bought it), I'd prefer to prevent another circuit breaker episode.

Quoted: I'm not an electrician but I'd bet it's the circuit breaker.  They are cheap and easy to replace.  Just be careful.  The hard part will be trying to coax a bulb to blow in order to test it.

ok, I'll look into it sometime this week I guess. I'm just pissed off cause I had a bunch of unsaved work open in photoshop this time, which, of course, I lost. Hopefully I can get this done with out electrocuting myself.

It sounds to me like that circuit may have too many lights on it.  Is it a circuit that is only for that room, or does it wind through several rooms first?

we had something like this happen.  every time we would turn on our shop lights, the breaker would flip.  after a bigger fuse, no more problem.  maybe the same thing is happening.

Quoted: Quoted: we had something like this happen.  every time we would turn on our shop lights, the breaker would flip.  after a bigger fuse, no more problem.  maybe the same thing is happening. Um, I'm enough of a weekend electrician to know how foolish that is.   Here's the thing--if the wire used is 14 gauge it can ONLY be safely fused at 15 amps.  Twelve gauge wire is fused at 20, ten at 30 amps.  Raising the fuse level invites a melted insulation and fire before the fuse blows.  That is bad for continued living in your house.   The answer is to use the correct fuse and reduce the load (stuff plugged in and drawing current) on the circuit.

Or rewire the circut.  

Quoted: Quoted: we had something like this happen.  every time we would turn on our shop lights, the breaker would flip.  after a bigger fuse, no more problem.  maybe the same thing is happening. Um, I'm enough of a weekend electrician to know how foolish that is.   Here's the thing--if the wire used is 14 gauge it can ONLY be safely fused at 15 amps.  Twelve gauge wire is fused at 20, ten at 30 amps.  Raising the fuse level invites a melted insulation and fire before the fuse blows.  That is bad for continued living in your house.   The answer is to use the correct fuse and reduce the load (stuff plugged in and drawing current) on the circuit.

not my house (renting).  i didnt do it, an electrician did.  hopefully the house wont burn down.

Quoted: It sounds to me like that circuit may have too many lights on it.  Is it a circuit that is only for that room, or does it wind through several rooms first?

+1

Quoted: Ok heres my problem. This room has 4 floodlight fixtures for lighting. Instead of burning out like normal bulbs, these ones "flash out" when I flip the switch on. That's all fine and dandy, except that it trips the circuit breaker everytime. I'm 3 for 3 on them going like this, pissed off is an understatement. Any idea what could be wrong? Is it the breaker? the switch? the fixtures? We're having an electrician come sometime in the future to work on something else, but I'd prefer to get some leads on this if I can, since there is only 1 more original bulb (that came with the house when we bought it), I'd prefer to prevent another circuit breaker episode.

Are they DC floods with a power supply?  There may be a badly designed powersupply with a current limiting issue.  You would need to replace the entire unit with a better designed one to eliminate this problem.  

For instance, I have a triple halogen fixture on a motion detector.  Every time a bulb goes, it flashes and then pops the motion detector.  Bad design in the motion detector.  At least it doesn't blow my breaker, it just stops working when a bulb blows.  I keep a spare.  When a bulb blows, I replace the motion detector, and then take the old one back for a free replacement.

After enough are returned, they might fix their design.  An MOV or Zener needs to be in the power supply circuit at the appropriate place.........

Is it a newer home? Is the circuit breaker an Arc-fault breaker?
An Arc-fault breaker is a new type of breaker that will sense an arc, like from a frayed extension cord. It will trip even with a light load if it senses an arc on it's circuit.

All new bedroom circuits since 2000 a required to use an Arc-fault breaker.
The breaker will look like a GFCI type breaker with the test button on the front of it.
The test button will be blue if it is an Arc-fault type, yellow if it is a GFCI type.

If it is an Arc-fault breaker, it is too sensitive and should be replaced. Square D had alot of problems with them when they first came out and recalled alot of them.

If it is a regular type breaker, I would replace that also.

First thing Id do is add up all of the wattages of all the tubes and figure out what current your drawing. Watts devided by volts. Compare to the breaker running the circut. If your under 10% or so of max current there could be several things involving the inrush peak. Loose connections are a big culprit that people dont think of, including at the swithch, breaker and all of the wire nuts in the circut. Im an industrial guy not residential/comercial type with a big history of power distribuiton and lighting stuff. Im sure the residental guys can also comment on the current inrush when it comes to ballast starters in flouresent fixtures. I dont really know how high they peak or if its even enough to matter. Time for another beer.

wow lots of replies. Its kind of tricky cause this is an older house, but all the fixtures in here are relativly new (not sure when exactly but definatly before 2000). As far as I know, the only thing on the breaker that pops is this room.
Breaker panel is GE brand, and the breaker is 15 amps.
All that's running when they go is my computer, monitor and an alarm clock, as well as an old cordless phone.
The fixtures appear to be 120v recessed flood lights. The bulbs I'm replacing them with are 65w "medium base BR30 shape" bulbs from Philips.

I've been meaning to check the connections in the switch, since the last time one popped off I took off the faceplate to check and saw some bare copper... I've just been too lazy to switch off all my stuff and check it all out.

Take the computer off the Circuit and the monitor as well.

What size wire do you have if it is 12guage and not 14 guage, then change the breaker out to a 20amp.

I didnt' see the total amps of service you have.

Besides being an overloaded individual circuit, one of the legs could be overloaded as well. I've had that problem before service was upgraded.

Basically electricity comes into your house on two 'legs'. They alternate one after another in the circuit box. Call them A and B. Circuit 1,3,5 are leg 'A', circuits 2,4,6 are leg 'B'. This is also how they make a 220v circuit, btw- combining both 110v legs into a 220v circuit.

So if your individual circuit isn't overloaded, you could have a bunch of things on the same leg - say a refrigerator, dehumidfier, tv, heater, etc.  The leg could be loaded up when you get to the light switch, turning it on pushes it over the edge. If they're spread out

It could also happen when you're just sitting there working and the compressor on the fridge kicks in.

The best way to tell this is to get a UPS backup. APC backups will ring when the power dips significantly (I don't know about all, but all the ones I have do that). You can also go down the the circuit breakers and see which things are on which circuits and plot it out that way. If your high draw items are on the same legs, it could becausing your problems.