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Posted By: redneck Halogen bulbs trip breaker. - 01/29/07 02:01 AM
Customer has complaint. He has recessed lights in the bathroom,and when the bulb blows,it trips the breaker. Bulbs are Halogen,120v,Sylvania double life,Capsylite Par 20.

Doesn't happen often,maybe a couple times a year. Breaker only trips when the bulb blows. Standard breaker,not GFCI,and lights are on separate circuit from Receps in Bath.

We didn't do the job,but he called me wondering what it could be.

Any ideas?????

Russell
Posted By: ShockMe77 Re: Halogen bulbs trip breaker. - 01/29/07 02:53 AM
If the circuit breaker is tripping it can only be one of three things: an overload, a short circuit, or a ground fault.
Posted By: LarryC Re: Halogen bulbs trip breaker. - 01/29/07 02:57 AM
Breaker trips also include physical shock, strong magnetic field, and over temperature.

I tend to doubt that any of these, are in fact the cause of this behavior.

Larry
Posted By: frenchelectrican Re: Halogen bulbs trip breaker. - 01/29/07 03:59 AM
there is good chance when the filment break it will delope a arc current like HID for a split sec that just enough to trip the breaker

that one possiblty i can think of

Merci , Marc
Posted By: RODALCO Re: Halogen bulbs trip breaker. - 01/29/07 06:08 AM
Check the loading on the circuit concerned.
If say for example a 16 Amp beaker runs at 14 Amps lighting load, the cold inrush current from all the lamps and the arc from the lamp failing may be just enough to trip the braker.

Is it always the same lampfitting or all over the place ?
Posted By: wageoghe Re: Halogen bulbs trip breaker. - 01/29/07 02:45 PM
I have a fixture (outdoor floodlight) with halogen bulbs (stab in, not screw in) and it (apparently) tripped the breaker when one the bulbs blew. I noticed that other lights (inside the garage) on the same breaker were not on, so I reset the breaker and found that the only thing amiss, at least that I could tell, was the blown bulb in the floodlight.
Posted By: Beachboy Re: Halogen bulbs trip breaker. - 01/29/07 07:06 PM
I have two 90 watt PAR 40 halogen floodlight bulbs in an outdoor light fixture. Every time a bulb burns out, it trips the 15 amp breaker. I wrote General Elecric lighting department asking their opinions on this, and all they did was send me an apology and a case of new flood bulbs.
Posted By: SolarPowered Re: Halogen bulbs trip breaker. - 01/29/07 08:39 PM
I'm thinking a breaker rated "HACR" might be a good workaround, if that's not what's already there. They would be more likely to hold while the lamp filament clears, but will still adequately protect the wiring.
Posted By: Rewired Re: Halogen bulbs trip breaker. - 01/29/07 10:27 PM
I remember back in my school days every time an overhead projector would burn out a lamp it almost always would trip the breaker. The breakers were Sq-D and located right in the room so it was not too troublesome to reset actually.

A.D
Posted By: Scott35 Re: Halogen bulbs trip breaker. - 01/30/07 12:02 AM
Marc hit the nail on the head!

Halogen Lamps have what is known as "The Halogen Cycle", which should be known for extended Lamp Life.

Simply put, to get the most life out of the Lamp, keep it as Horizontally Level as possible (+/- 4°).
This causes the Atomized Fillament to land back on the Filament, during operation.

When the Filament fails under load, the Atomized material allows an arc to be sustained, and the Arc has no Resistance (actually has negative resistance) - so there is a large increase in load current, which trips the breaker.

Same would occur if any Non-Ballasted Discharge Lamp was thrown across the line.

Scott35
Posted By: redneck Re: Halogen bulbs trip breaker. - 01/30/07 03:11 AM
Thanks for the help Guys. This one had me stumped.

I told the customer today, that I didn't know the answer,but I knew a place I could find it.

Thanks again.

Russell
Posted By: brianl703 Re: Halogen bulbs trip breaker. - 02/01/07 04:04 PM
http://members.misty.com/don/bulb1.html#wbs

Why burnout is sometimes so spectacular
When the filament breaks, an arc sometimes forms. Since the current flowing through the arc is also flowing through the filament at this time, there is a voltage gradient across the two pieces of the filament. This voltage gradient often causes this arc to expand until it is across the entire filament.
Now, consider a slightly nasty characteristic of most electric arcs. If you increase the current going through an arc, it gets hotter, which makes it more conductive. Obviously, this could make things a bit unstable, since the more conductive arc would draw even more current. The arc easily becomes conductive enough that it draws a few hundred amps of current. At this point, the arc often melts the parts of the filament that the ends of the arc are on, and the arc glows with a very bright light blue flash. Most household light bulbs have a built-in fuse, consisting of a thin region in one of the internal wires. The extreme current drawn by a burnout arc often blows this built-in fuse. If not for this fuse, people would frequently suffer blown fuses or tripped circuit breakers from light bulbs burning out.
Although the light bulb's internal fuse will generally protect household fuses and circuit breakers, it may fail to protect the more delicate electronics often found in light dimmers and electronic switching devices from the current surges drawn by "burnout arcs".
Posted By: Texas_Ranger Re: Halogen bulbs trip breaker. - 02/01/07 11:37 PM
Around here in areas with low impedance feeders and houses close to the transformer that's a pretty common occurrence even with incandescent bulbs. Ever since they put in new underground wiring in the street we occasionally had tripping breakers when bulbs blew.
Posted By: resqcapt19 Re: Halogen bulbs trip breaker. - 02/02/07 02:09 AM
The most common reason for a breaker to trip on lamp burn out is that a small section of the filament drops across the lamp bus creating a short and drawing enough current to trip the breaker.
Don
Posted By: resqcapt19 Re: Halogen bulbs trip breaker. - 02/02/07 02:11 AM
Scott,
Quote
When the Filament fails under load, the Atomized material allows an arc to be sustained, and the Arc has no Resistance (actually has negative resistance) - so there is a large increase in load current, which trips the breaker.
Negative resistance would mean that you are creating power. I don't think that is possible.
Don
Posted By: resqcapt19 Re: Halogen bulbs trip breaker. - 02/02/07 02:13 AM
Scott,
Quote
When the Filament fails under load, the Atomized material allows an arc to be sustained, and the Arc has no Resistance (actually has negative resistance) - so there is a large increase in load current, which trips the breaker.
Negative resistance would mean that you are creating power. I don't think that is possible.
Don
Posted By: Trumpy Re: Halogen bulbs trip breaker. - 02/02/07 06:59 AM
Russ!,
Good to see ya posting mate!. [Linked Image]
For those of you that don't know, this fella used to be ga56sparky, one of the first people that registered here.
Posted By: redneck Re: Halogen bulbs trip breaker. - 02/03/07 01:07 AM
Hi Mike. I still come here and read when I can.

I see ya'll still let Roger and Bob in here.
Posted By: Trumpy Re: Halogen bulbs trip breaker. - 02/03/07 10:40 AM
Ahh yes Roger and Bob.
Good to see they hung around. [Linked Image]
Posted By: NJwirenut Re: Halogen bulbs trip breaker. - 02/03/07 05:13 PM
Quote

Negative resistance would mean that you are creating power. I don't think that is possible.

In the strictest sense, you would be correct. But a negative resistance region is characteristic of some exotic semiconductor devices, such as a "tunnel diode"
http://en.wikipedia.org/wiki/Tunnel_diode
http://en.wikipedia.org/wiki/Negative_resistance





[This message has been edited by NJwirenut (edited 02-03-2007).]
Posted By: Scott35 Re: Halogen bulbs trip breaker. - 02/03/07 11:47 PM
Don (Resqcapt13):

Quote



Negative resistance would mean that you are creating power. I don't think that is possible


I guess that would be another way to describe it, but the term is being applied as to the characteristics of Plasma, and the way it becomes more conductive as the Plasma increases in size, along with the fact that there is no opposition to current flow.

To me, the term "Negative Impedance" may be better suited for the characteristics of a Plasma derived from an AC source.

The term "Negative Resistance" was used when I first began studying Plasmas and related Lighting (Discharge Lighting). It kind of stuck, and became the default term.
That was back in 1984.

Guess it's time to get a new term!

Scott35
Posted By: redneck Re: Halogen bulbs trip breaker. - 02/04/07 12:04 AM
Scott,I understood enough of what you were saying for it to make sense. I thank you and the others.

Russell
Posted By: SteveFehr Re: Halogen bulbs trip breaker. - 02/04/07 12:52 AM
Yeah, I don't think "Negative Resistance" is a very appropriate term, considering the resistance is never negative, it just decreases with current levels.
Posted By: Scott35 Re: Halogen bulbs trip breaker. - 02/08/07 04:36 AM
Russell (Redneck)

Quote

Scott, I understood enough of what you were saying for it to make sense.
I thank you and the others.

Glad you could make sense of my posted information, as the last post I made was in reply to Don's comment about Negative Resistance, and really had nothing very helpful to add!
[Linked Image]

Steve:

Quote

Yeah, I don't think "Negative Resistance" is a very appropriate term, considering the resistance is never negative, it just decreases with current levels.

I agree!

Scott35
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