# Short Circuit but Breaker does not trip



## vino82 (Jan 29, 2010)

My wife plugged in her vacuum soon as she turned it on the power went out to the circuit. My first intuition is to check the breakers to see if it tripped. I take a look and no breakers are tripped (I have the old push button breakers) but the entire circuit went out (all the outlets in the room and some random lights). I take out my meter and check the plug that my wife plugged into, no power but I have an infinite short between the hot and neutral. the same goes for all of the other plugs on the circuit. I take out the outlet to see if the short occured there, nope it looks fine. I did find a junction box in the cellar that is feeding that circuit, I pull the wires apart in the box and narrow it down to one of the wires that has a short between the hot and neutral. I check the plugs upstairs again, no infinite short at any of them, however I am reading 53 ohms between the hot an neutral. How is it that I have a short but the breaker does not trip and should I be reading 53 ohms? 

Thank you,
Ryan


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## joed (Mar 13, 2005)

Any device plugged into the circuit will show as short. You are looking in the wrong place. If the breaker is not tripped then you need to look for an open not a short circuit.


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## vino82 (Jan 29, 2010)

Is it correct to say the short im reading could be the bulbs that are in the lights attached to the circuit? For this circuit to be working fine for weeks now (we just moved in) and suddenly it going out is peculiar. If there is an open somewhere down the line, how is it that plugging in the vacuum and turning it on suddenly cause an open in the circuit somewhere else other than behind the outlet which she plugged into (which has only one wire)?

Thank you for the advice,
Ryan


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## HouseHelper (Mar 20, 2007)

vino82 said:


> Is it correct to say the short im reading could be the bulbs that are in the lights attached to the circuit? For this circuit to be working fine for weeks now (we just moved in) and suddenly it going out is peculiar. If there is an open somewhere down the line, how is it that plugging in the vacuum and turning it on suddenly cause an open in the circuit somewhere else other than behind the outlet which she plugged into (which has only one wire)?
> 
> Thank you for the advice,
> Ryan


If there was a loose connection somewhere in the circuit, the surge from the vaccum could have caused the connection to open. If the entire circuit is out, suspect a loose connection in the panel.... most likely on the neutral (white) wire.


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## joed (Mar 13, 2005)

Vacuum is a high current device. It is one of the most common devices to cause a connection to go open. If the breaker is not tripped you do not have a short. You are reading the light bulbs filiments or something else plugged into the circuit.


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## vino82 (Jan 29, 2010)

You all have been very helpful, once Im home I am going to check for a loose neutral in the panel. Is it possible that there may be a faulty splice in a junction box that could have opened upon starting of the Vacuum?

Thank you,
Ryan


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## HouseHelper (Mar 20, 2007)

vino82 said:


> You all have been very helpful, once Im home I am going to check for a loose neutral in the panel. Is it possible that there may be a faulty splice in a junction box that could have opened upon starting of the Vacuum?
> 
> Thank you,
> Ryan


The "open splice" could be anywhere... the fact the the entire circuit is affected means it has occured either at the panel or between the panel and the first outlet.


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