Home>Discussions>ELECTRICAL & LIGHTING>Main breaker off...a light still on?
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valhalla
Main breaker off...a light still on?

I have a Square D box with 100 amp service. Everything has worked fine for the 12 years I have been here and for a total of 25 years between the last person here and me. An unlicensed electrician putting in GFI's, intentionally shorted out an outlet with a jumper wire to trip the breaker. That seemed like a bad way of doing things. It tripped the breaker for that outlets circuit as well as the main breaker. With the main breaker off there were still some lights on in the basement. Obviously if the main breaker is off nothing should have power. I told him the main breaker was probably old and by shorting out the outlet like he did, it tripped the breaker. He was trying to tell me I need a new circuit breaker box and rewiring for $850 to $1500. I sent a picture of my opened box to a licensed electrician to verify that I just need a new main breaker (about $27) He concurred and said that main breakers can cause this by not shutting off all the way more or less. My picture of the box is too big for this post. If you want to see it I can email it to you. Can you give me your opinions please?

Thank you!

Valhalla

A. Spruce
Re: Main breaker off...a light still on?

A replacement of the breaker, maybe, but rewiring? And, rewiring what, the panel or the circuit that the unlicensed goon shorted out? I'd go with the professional guidance and leave the goon on the street corner where he belongs.

JLMCDANIEL
Re: Main breaker off...a light still on?

Ditto to Sprucey's answer.

Jack

sparky1
Re: Main breaker off...a light still on?

Ive shoted out circutis to find breakers.. but i was pretty green at the time!!:D sometimes a bad breaker will not open all the way causing voltage to still be going though.. we just replaced a 2500 amp switch a couple weeks ago that wouldnt open. Ya just need a new breaker

canuk
Re: Main breaker off...a light still on?

I'm trying to figure how shorting a branch receptacle would trip the main breakers.

JLMCDANIEL
Re: Main breaker off...a light still on?
canuk wrote:

I'm trying to figure how shorting a branch receptacle would trip the main breakers.

All you need is excessive load on one leg.

Jack

canuk
Re: Main breaker off...a light still on?
JLMCDANIEL wrote:

All you need is excessive load on one leg.

Jack

I don't think I would want to holding that shorting wire ( or paper clip ) when 100 amps comes down the line :eek::D

JLMCDANIEL
Re: Main breaker off...a light still on?
canuk wrote:

I don't think I would want to holding that shorting wire ( or paper clip ) when 100 amps comes down the line :eek::D

There could have already been 90 amps of load on that leg, the rest of the house had power until the short.

Jack

canuk
Re: Main breaker off...a light still on?
JLMCDANIEL wrote:

There could have already been 90 amps of load on that leg, the rest of the house had power until the short.

Jack

Perhaps-----------

meternerd
Re: Main breaker off...a light still on?

As a utility electrician, I'm thinking "Power Diversion". Some loads tapped off the line side of the meter. VERY Dangerous, since there's no breaker protection. Might at least be worth a look.

Re: Main breaker off...a light still on?
JLMCDANIEL wrote:

There could have already been 90 amps of load on that leg, the rest of the house had power until the short.

Jack

True, and I would exercise the main breaker a few times before I replaced it. But, not by shorting out a circuit!

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