"simple" electrical problem cant solve

[BACyclone]

I like your presence of mind to tell your wife to leave the house....

 

[Isualum13]

I ran into a similar issue when installing a light/exaust fan in my bathroom recently. Replaced the wires to the junction box as they were old and it needed to be done. Connected the wires just as they had been disconnected and had nothing. No breakers were tripping either so didnt know what to do. Turned off the breaker to be safe and went to bed. Called my electrician friend the next day and he was there within an hour. He had been working accross the street so it was pretty convenient. Had the light and fan working in no time.

As long as the work you did is close to being right, an electrician should be able to come in an diagnose the issue fast and get you running in little time at little expense. Especially since you seem to have all the parts that would be needed.

 

[discydisc]

I think you have the hot and neutral wires connected properly because the lights worked fine when the grounds were not connected. Since grounding the system flips the breaker immediately (before turning on the lights), I think one of your hot pigtails is being grounded to the metal box it is in.

This is a dangerous situation. It means that one of your boxes is essentially wired to 120V. Electrocution hazard.

The safest course of action is to stop reading and call an electrician. If you are too stubborn to do that, then here is how I would debug if I was you

1. Turn off the breaker and leave it off until step 4
   
2. Glance at each box and look for this type of fault. Hopefully you can spot it
   
3. If that doesn't work, find the first box that you ran wires to from the breaker panel. Do these steps at that box only!
   • separate the ground pigtail
   • find the conduit the comes directly from the breaker box
     
   • connect the bare ground wire from that conduit to the green screw on the metal box
   • leave all other grounds floating in air, not touching each other
4. Walk back to the breaker box and flip the breaker on
5. If the breaker trips, then you know that the short is in that first box. Focus your effort there
6. If the breaker doesn't trip after a few seconds, then turn it off and continue.
   
7. Go back to the first box and connect one downstream ground wire to the ground wire that you connected to the green screw. You should have the ground from the breaker panel connected to the green screw and one downstream circuit. The other ground wires should still be floating in air and not connected.
   
8. Repeat the breaker test. If it trips, then your shirt lies somewhere in the circuit that you just tied to the ground. If not, turn the breaker off and repeat.
9. Keep fanning out away from that first box until you find the short.
   
10. Only leave the breaker active for a few seconds at a time. Until you fix the problem, the breaker must be off before you walk away from the panel

That is how I was debug if I was you. But I am not you. I would debug by unwrapping all the pigtails, tell my wife to leave the house, turn the breaker on, and then measure which box is at potential using a multimeter set to AC volts. But this places you in the presence of an electrocution hazard, and you admitted to being a dunce, so I like avoiding that.

good luck
H

Why even turn the AC on? If it is shorting he should be able to disconnect grounds one at a time until he no longer reads continuity/resistance/ohms between his hot wire and ground, right? Once the conductor that is shorted to ground is ID'ed its just a matter of finding out where it is shorted and resolve the problem.

 

[cyphoon]

Why even turn the AC on? If it is shorting he should be able to disconnect grounds one at a time until he no longer reads continuity/resistance/ohms between his hot wire and ground, right? Once the conductor that is shorted to ground is ID'ed its just a matter of finding out where it is shorted and resolve the problem

That would work in theory, but

• It requires that he have an ohmmeter and knows how to use it.
  
• He would have to understand that he could be reading a short through the terminals of a switch to another wire, or through the lights if they are incandescent.
  
• It requires that he pull some hot wires out and remove their caps so he can connect the leads of his meter. This gives him a chance to make another mistake when recaps them and shoves them back into the box (a mistake he has already made once)
  
• simply moving hot wires around to test them could remove the short, and make it frustrating to find the problem.

Turning on the AC with some boxes not properly grounded is a risk. No question about that. But doing so for a few seconds while his rear is planted at the breaker box seems acceptable to me.

It might make more sense to start farthest away from the panel, so the system keeps tripping until he finds the culprit. More challenging to explain that though.

H

 

[cyphoon]

btw, it is conceivable that one of the light fixtures is defective and is shorting hot to ground inside it. Have never personally seen this, so consider it a remote possibility. You are still the likely culprit.

H

 

[EvilBetty]

I think you have the hot and neutral wires connected properly because the lights worked fine when the grounds were not connected. Since grounding the system flips the breaker immediately (before turning on the lights), I think one of your hot pigtails is being grounded to the metal box it is in.


H

this was it. a bur on a romex connector coupled with me tightening the connector too much. hot wire connected with that metal box and subsequently the ground. I did call an electrician and that is what they discovered in about 30 min of noodling around with it.

thanks