I recently replaced a light switch. I had a very hard time getting this switch to work because when I would put the switch in the wall, it would no longer work. I later traced this down to the wire moving slightly off the screw holding it in the switch. I made a circle out of the wire and screwed the wire onto the switch. Since the wire is now in a circle, it can’t move around off of the screw. When I put the switch in the wall and went to go turn the breaker back on, it tripped about 10 times in a row. Finally the breaker stayed put and the light switch seems to be working.

What would cause the breaker to trip so many times in a row and then finally stop ‘breaking’? Should I be worried?

  • Is the box the switch is mounted into made of metal or plastic? – ThreePhaseEel Nov 22 '17 at 4:43
  • It’s a metal box – adivis12 Nov 22 '17 at 12:36
  • Arc welding 101 keep hitting the electrode with power and at some point the metal will be all used up, in your case the wire was the electrode. I would check the wiring to see how badly the insulation is melted, wow 10 times really? – Ed Beal Nov 22 '17 at 14:23
  • 10 might have been an exaggeration, but my mistake is not the point, and in my opinion, should't keep being highlighted. The point is to get the details out here on the Internet so others can learn from my mistake. Mistakes happen especially in times of frustration. – adivis12 Nov 22 '17 at 15:28
  • Do you mean the insulation around where the wire is connected to the screw? Or insulation at any point along the wire from the fuse box to the switch? That will be difficult to tell. – adivis12 Nov 22 '17 at 15:34

Shepherd's hooks

Putting a shepherd's hook on the wire, fitting it, squeezing it so it tightly wraps around the screw about 200 degrees (preferably clockwise so it doesn't spread), and tightening the screw to spec -- is the only proper way to use a screw terminal on a receptacle or switch. (unless the device's written instructions specifically give another method, e.g. breaker lugs or Leviton's screw-and-clamp system). Backstabs are legal, but unreliable, and properly done shepherd's hooks are the way to go.

The fastest way is use the lonely hole on your wire stripper, that's what it's for, and the pliers on the end of it to squeeze the hook once it's on the screw. You can get pretty fast at it.

Wires are held to the screw both by being wrapped around the screw and tightened to spec. It's a very solid connection that will resist tugging, twisting, and being shoved back into the box with stiff #12 wire. You can't pull it off like you can a backstab. If it doesn't feel solid to you, it is wrong.

If it's not working for you, feel free to ask a question for us to review your technique. Some edge cases can be tricky.

Watch out for ground wires touching screws or metal box

Often trouble happens when you stuff it back in the box and a ground wire touches a hot screw. Blam, breaker trip! But it is also bad if a ground wire touches a neutral screw - that will cause GFCI and AFCI trips. Manage ground wires carefully and if necessary, wrap the receptacle/switch with tape to cover the screws (In the only direction that makes sense). 3 loops is sufficient.

The same issue can occur touching the side of a metal box, especially if there is a bit of a drywall gap, which can let the device tilt compared to the box.

Don't reset breakers 10 times

When a breaker trips once, review your previous work and fix it. Do not keep resetting the breaker! The service panel will never dispense a food pellet!

What you actually did was set the wire on fire, causing arcing damage to the wire until the arc damage removed enough copper for it to no longer short. Or, you broke the breaker. Both are still dangerous. Find the root problem (the scorch and sputter damage will be apparent) and replace the breaker.

A breaker's thermal trip mode (the slower trip) is designed to trip before the wire gets hot enough to start a fire. Once power is removed, breakers cool down faster than wires, so repeatedly resetting them defeats their thermal protection. If it trips other than instantly, give the wires 10 minutes (3 songs) to cool before resetting.

But here's the thing. You are probably making lots of other mistakes we'll never know about. Mains wiring is lethal and brns down houses, usually later. If you own this house, and plan to sell it, the home inspection will find bad homeowner work, and likely force you to pay an electrician to take apart everything, check and fix it. Take your time, let yourself learn, do it perfect.

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    Heck, "screw meets box" is enough to cause the problem the OP is describing given that they are dealing with a metal box... – ThreePhaseEel Nov 22 '17 at 12:37
  • To be clear, it wasn’t tripping until I put the switch back into the metal box. If it was my wiring job that was the problem, it would have tripped before I put the switch back into the box. Also, I have a home wiring book I skimmed through before hand and was actually making shepherds hooks. It wasn’t working. Is it a problem that in the current state the wires is touching itself in the loop I made? It’s basically a shepherds hook that loops back on itself. – adivis12 Nov 22 '17 at 12:43
  • Also what’s the best way to make sure my breaker is ok? Just taking my no-touch tester and making sure it stops beeping when I flip the breaker again? – adivis12 Nov 22 '17 at 12:48
  • I only put one loop of electrical tape on after wiring. Maybe when I push the switch into the box the tape is being removed from the screw, touching the metal box, tripping the breaker – adivis12 Nov 22 '17 at 12:52
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    That's easy! The #4 pic screw is clamping down on insulation, that shouldn't work at all. The overlap in #1 is nope! #2-3 are great but flip them so they go with the screw, not against. The 270 degree curl in #2 is fine, just really hard to do wirhout removing the screws entirely. Did you notice the screws being SUPER stiff when they were almost all the way out? That's a detent to keep the screws from coming out, they are supposed to be captive. Looks like you overpowered them. – Harper - Reinstate Monica Nov 23 '17 at 6:30

You clearly have had and probable still have a problem. You don't correct a breaker tripping problem by continuing to simply trying to reset the breaker. That breaker is tripping for a reason. With your knowledge level, I recommend you seek assistance. P.

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