light bulbs blowing

[Riograndeelectric]

received this email from a customer I did a remodel for 2 years ago. the lights are on a new circuit non AFCI wired under 2005 code.
I Can not remember if these are incandescent single 60 watt or halogen 150 watt.
I do no think they are CFL though. any ides what would cause this?


"In the remodel you installed two sconces on the stairs. The two sconces are on the same switch as a light at the foot of the stairs. Last week the bulb on each sconce blew out simultaneously. When I replaced one of the bulbs it immediately blew out. Seems like a problem".

 

[480sparky]

Open neutral.

Bad lamps.

Poor connection at base of lamp socket.

 

[jwjrw]

Open neutral.

Bad lamps.

Poor connection at base of lamp socket.

Since they blew together I would be looking for an open nuetral as well.

 

[milehiwire]

Hey Rio,

Close to 85 and Oxford here. My guess is coincidence

 

[sameguy]

Foot of the stair not blowing? Worked over 1 year. Tell them to stop getting lamps from the dollar store. Did some one do electrical since you?
Go do a service call and sell them good lamps 130v, brass base, multi- filament holder.
I had a problem with florescent fixtures, turned out the upstairs had turned into an Irish Dance studio and was vibrating the lamps out of the old fixtures; new tomb stones and back to working again.

 

[jwjrw]

Id start pulling fixtures down and would probably hook a keyless up to see it worked properly.

 

[hunt4679]

seen it too many times I wouold say neutral problem

 

[jes25]

Customers always exaggerate, so keep that in mind.

It can't be a neutral unless he used a multiwire circuit which I doubt.

The only legitimate thing I've really seen that can cause good lamps to good out quickly is vibration from a slamming door or something. Of course someone may have been messing with the circuit and somehow applied 240V to the circuit.

 

[Riograndeelectric]

Customers always exaggerate, so keep that in mind.

It can't be a neutral unless he used a multiwire circuit which I doubt.

The only legitimate thing I've really seen that can cause good lamps to good out quickly is vibration from a slamming door or something. Of course someone may have been messing with the circuit and somehow applied 240V to the circuit.

Not multi wire branch circuit. I only run single wire branch circuits.
just for the reason of some one messing with it and applying 240 volts.
I think right about bad bulbs. circuit and lights have been working fine for 2 years + . Most likely will install 130 volt bulbs.

 

[K8MHZ]

It can't be a neutral unless he used a multiwire circuit

Not true. The neutral can be bad at the panel. Think about it, isn't the entire residence on a multi-wire circuit that feeds the panel?

 

[jes25]

Not true. The neutral can be bad at the panel. Think about it, isn't the entire residence on a multi-wire circuit that feeds the panel?

True if the service neutral was bad, but there would be other symptoms like all the bulbs blowing out.

 

[480sparky]

True if the service neutral was bad, but there would be other symptoms like all the bulbs blowing out.

Not if it's 1.) intermittent, and it was only an open neutral for a moment when the lamps were turned on and/or 2.) the voltage differences aren't that great, meaning the system is well-balanced, but enough of an imbalance to find the weakest link..... the lamps.

 

[jwjrw]

Not if it's 1.) intermittent, and it was only an open neutral for a moment when the lamps were turned on and/or 2.) the voltage differences aren't that great, meaning the system is well-balanced, but enough of an imbalance to find the weakest link..... the lamps.

But since there was 3 lamps on that circuit and only 2 blew........ Probably not the cause ? 480 what say you?

 

[480sparky]

But since there was 3 lamps on that circuit and only 2 blew........ Probably not the cause ? 480 what say you?

2 lamps were a little bit weaker than the third. Not every lamp is created 100% equal.

 

[jwjrw]

2 lamps were a little bit weaker than the third. Not every lamp is created 100% equal.

And a service neutral can cause different areas of the house to have a problem depending on load and phase.

 

[480sparky]

And a service neutral can cause different areas of the house to have a problem depending on load and phase.

It can, but not necessarily will. It depends on how well-balance the loads are.... something we cannot determine here at our keyboards. Especially if it's an intermittent open neutral.

 

[jwjrw]

It can, but not necessarily will. It depends on how well-balance the loads are.... something we cannot determine here at our keyboards. Especially if it's an intermittent open neutral.

Here I see that a whole lot. More so that than losing a phase. Ive seen a few appliances burnt up but no light bulbs. Usally just have parts of the house dead at times.

 

[zappy]

When you say "well balanced" Do you mean, each phase has about the same amps on it? Like at the service panel or sub-panel. Also i've heard that if you have alot more load on one phase then the other phase, your electric bill will be higher. Is that true?

 

[WinZip]

Could be the neutral connection from the 3 rd fix from the end or the 2 nd from the end and could be the lamps like someone else said, my guess is loose neutral.

 

[480sparky]

When you say "well balanced" Do you mean, each phase has about the same amps on it? Like at the service panel or sub-panel. Also i've heard that if you have alot more load on one phase then the other phase, your electric bill will be higher. Is that true?

Balanced means, in this case, the resistance placed on each 'leg' to the neutral is close the same value. With an open neutral in this case, the voltage difference will be minimal, but possibly enough to take out a few 10? lamps.