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jgond78
Weird power outage!!

This morning around 6a.m. a portion of my homes power went out. I checked the breaker box, and found no breakers popped. So not knowing what else to do, i called an electrician. Who hasn't called me back yet. While i was waiting for his call, the power just came back on around 9a.m. What would have caused this? Should i be worried or relieved?

Thank You!

Blue RidgeParkway
Re: Weird power outage!!

You may have lost half a phase. (one side of the two "hot" leads that feed your electrical panel). Do you have any 220/240 electrical appliances (electric water heater, clothes dryer, range/oven?

Was it windy outside? Ice falling? Dead animal hanging from the power lines, or find one stiff down below? Could be something from the pole, the masthead, behind the meter, or in your panel.

Fencepost
Re: Weird power outage!!

Could have been a loose connection anywhere between the power company's transformer and your electrical panel. You should have an electrician check all of the connections between the meter base and the panel to make sure they are OK. The power company is responsible for everything up to the meter base; if the electrician finds nothing wrong you should call the power company.

To expand on BRP's post, there are two "hot" lines coming into the home which have 240V between them. Between each one and neutral/ground is 120V. From an electrical engineering viewpoint, this represents a single "phase" with a "center-tapped secondary." This center tap on the secondary side of the transformer is grounded and connected to the neutral to provide 120V/240V split single-phase power.

You may hear people refer to each of the "hot" lines as different phases. This is not correct semantics; they are different POLES of the same PHASE. (BRP said "half a phase" which is better terminology than what most people would use -- many would say that you "lost a phase," which is incorrect.)

As an oversimplified graphical example, imagine that you are riding a bicycle equipped with clips (the clips allow you to provide power pushing and pulling). While you push down with one foot, you lift the other foot, and vice versa. Your legs are like the two poles of the phase providing 240V. If you remove your left foot from the pedal, you are still able to provide power to the bicycle but only at half the force, or 120V. (Imagine the seat post as "neutral." If you weren't attached to the seat post, you could provide 240V to both pedals, but you couldn't provide 120V to a single pedal.)

goldhiller
Re: Weird power outage!!

Should i be worried or relieved?

I guess I'd be hoping that it goes out again before he gets there and stays that way long enough to find the problem. It'll be much more difficult to trace/find the problem if there's voltage everywhere when he arrives.

The problem might also be inside a junction box somewhere inside the house. Ugh.

Here's wishing you good luck.

A. Spruce
Re: Weird power outage!!
goldhiller wrote:

The problem might also be inside a junction box somewhere inside the house. Ugh.

That would be my first guess and has usually been the problem in most situations I've encountered.

Blue RidgeParkway
Re: Weird power outage!!

While you're waiting for your electrician to arrive, it wouldn't hurt to contact your electrical utility and make an inquiry. (If you saw crews working nearby - be sure to let them know).

jgond78
Re: Weird power outage!!

I had the city power company come out today. They tracked it down to the main breaker in my electrical box. He also mentioned that i should replace my current box and upgrade it to a 200 amp service. I have an old Federal Pacific Stab lock box, 100 amp service.

Thanks for everything!!

Blue RidgeParkway
Re: Weird power outage!!
jgond78 wrote:

I had the city power company come out today. They tracked it down to the main breaker in my electrical box. He also mentioned that i should replace my current box and upgrade it to a 200 amp service. I have an old Federal Pacific Stab lock box, 100 amp service.

Thanks for everything!!

You're welcome.:)

Ernie_Fergler
Re: Weird power outage!!
jgond78 wrote:

I had the city power company come out today. They tracked it down to the main breaker in my electrical box. He also mentioned that i should replace my current box and upgrade it to a 200 amp service. I have an old Federal Pacific Stab lock box, 100 amp service.

Thanks for everything!!

I would get two or three quotes to upgrade your service and panel box. 200 amps should be about right depending on the size of your abode, that is.
Maybe someone on this board who is not an electrician has the time to Google and post the problems with FP panels.

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