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Discussion Starter · #1 ·
Having a really bizarre issue, I'm completely baffled.

- High rise condo built in 2003. So conduits/BX used extensively.
- Renovating the kitchen. Moved a light switch, added a plug, nothing major. Did NOT touch the stove circuit.

- Stove circuit was hot and had no problems.
- Plugged in stove. Tripped the unit MAIN breaker. 40's not tripped.
- Checked the 240 outlet. Looks like some nicked wires, so taped them all up.

- Turn off 40's, engage the main breaker. Stove is plugged in. Try to reset the 40's... trips the main again.

Stove is brand new, so I'm considering it's faulty, but that's like a 1 in 1000 chance probably.

Main questions

1) How can the circuit be hot and not trip the breaker?

2) Why isn't my 40A breaker going? Why does the main keep tripping?

3) What are my steps to troubleshooting?


Thanks!!
 

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I=E/R
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Stove is brand new, so I'm considering it's faulty, but that's like a 1 in 1000 chance probably.

Main questions

1) How can the circuit be hot and not trip the breaker?

2) Why isn't my 40A breaker going? Why does the main keep tripping?

3) What are my steps to troubleshooting?


Thanks!!
What do you mean the stove is brand new? Did it work before you started working on the kitchen?
Your main could trip first because of the existing load that is on the panel before you connect the stove.
If this is a new stove, who wired it and is it cord and plug or direct wiring?
 

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maybe the 40 has gone bad and is shorting to the main. good sparkies on this site will br along for more insight
 

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Mad Scientist
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If the breaker doesn't trip unless the stove is plugged in, odds are good that the problem is in the stove. If the breaker trips immediately, it sounds like there's a dead short in the stove. I'd start by checking the terminals where the cord is attached to the stove.

As for the main tripping instead of the 40A stove breaker, that's just the way it goes sometimes. Under a dead short, there might be maybe 10,000A flowing for a millisecond or two. It's essentially random which breaker along the path will trip.
 

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You talking to me?
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I would expect the 40 to trip first but unless you are dealing with brand new breakers, all bets are off. While all major manufacturers recommend you exercise your breakers annually, I have yet to meet a person (other than myself) that does so. That can allow a breaker to become stiff and not trip as designed.

The 40 amp breaker could be bad as well and just not tripping as it should.


If the stove is brand new and no work was done to the receptacle or it's wiring, I would suspect it is the stove. (given that receptacle worked before).

If you have a continuity tester, I would start with checking for a short in the appliance by checking for continuity from ground to each of the "hots" and the neutral at the plug. You should have no continuity from ground to anything else.
 

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Discussion Starter · #6 ·
We didn't want the appliances when we bought it so the previous owner took them. One would assume the stove was in a working state.

So brand new stove, it has a plug, came that way. I'll test the continuity on the plug and report back.

The wire is likely 8-3? Or would it be 8-4? I can only imagine having to fish a new one of those, they must be stiff as hell. I'm in North America, I'm assuming it will still be BX (armored) cable that has to be run in the conduit?

I'm trying to ease my mind that I didn't nail/drill/something the stove circuit while working on the kitchen - but surely, that would have tripped the breaker without any load on the circuit.
 

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I=E/R
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So, this new stove has never worked and it has a plug. Who installed the line cord on the stove? Does the line cord have 4 prongs? The cord could be connected incorrectly to the stove.
 

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Discussion Starter · #8 ·
It was delivered with it attached. I would assume it comes like that from Whirlpool? Or did the appliance company do it?

I'm quite sure it was 4-prong.
 

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Discussion Starter · #12 ·
Nope, it was fine. So he came today and opened it up.

There's 4 screws that hold the main control panel to the frame. One of those was piercing one of the wires :eek: Right from the factory.

So.. what are the odds? Guess I should buy a lotto ticket.
 

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#1 HAWKEYE FAN
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as as appliance repair tech this kind of piqued my curiousity, can one of you electricians explain to me why his main breaker was tripping and not his range circuit breaker. I have never seen a short in a range trip the main breaker.
 

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One possibility would be that the main panel already had a heavy load for what ever may have been active in the house and the short caused a surge that put it over the top and the main just responded faster than the stove breaker.
 

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" Euro " electrician
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as as appliance repair tech this kind of piqued my curiousity, can one of you electricians explain to me why his main breaker was tripping and not his range circuit breaker. I have never seen a short in a range trip the main breaker.
One possibility would be that the main panel already had a heavy load for what ever may have been active in the house and the short caused a surge that put it over the top and the main just responded faster than the stove breaker.

A7ecorsair have most the answer correct and I will expand this little more with the breakers there is a trip curve and like example stove and main breaker I know both are diffrent size but if you look at the trip curve when it short circuiting the trip curve is very simauir and it will not matter which breaker will trip out first some case both at the same time.

I did managed to trip the main breaker from time to time on 480Y277 system or 415Y240 system with the RCD { simauir to the GFCI }

And with main breaker tripped out hard from the short circuit if knowen like example range circuit leave that breaker off to the range and check it out first why it cause to kick it out as someone say a tech person found a short from factory that why I always ring it out to make sure there is no short no matter how trival it is.

Merci,
Marc
 
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