Backstabbed Electrical Connections

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  #1  
Old 01-28-04, 06:38 AM
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Backstabbed Electrical Connections

I've seen several comments on this forum about backstabbed connections and am wondering why they're a problem.

Backstabbed connections are as common as dirt around here. I've opened up hundreds of them over the years and can only recall one bad connection.

I would love to see some discussion about the pros and cons of backstabbing.
 
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Old 01-28-04, 06:57 AM
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There's usually no problem if the circuit is never overloaded or near overload. However, when the wires repeatedly heat up and cool down, they eventually cause metal fatigue on the piece of spring steel holding the wire. This is why the moment of failure is often associated with running a vacuum cleaner.

I have backstabbed connections in my house too (not of my own making), and I'm not going to go around changing them until they fail. So I'm somewhere in the middle. I don't make them, but I don't correct ones that are still working okay either.
 
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Old 01-28-04, 02:01 PM
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Thanks John-

I use them, but was wondering if that might be a problem someday. The one failure I saw was in my house and it looked like the receptacle had been broken when it was stabbed. I replaced it and it's been fine ever since.
 
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Old 01-28-04, 02:35 PM
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I have personally never seen a failure due to a backstab, but I have heard of them.

I am with John. My house has them and when I find them I fix them, but I don't go looking for them. I do not make them when installing an outlet or a switch.
 
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Old 01-28-04, 06:22 PM
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I’m not an electrician but in two of my homes and in a friend’s home, I’ve seen three failures of backstabbed outlets. I bought a new home in 1970. After about 6 months I turned on a table lamp in the living room and heard a sizzling sound. Noise was coming form a duplex. I found the neutral wire had turned dark brown for about 1inch. This house had aluminum wiring, but I don’t think it caused the problem. The backstab contact consisted of a small piece of flat spring that was no longer “springy”, and also dark in color. It had obviously been overheated. I repaired it by using a new outlet’s screw terminals. Three or four weeks later, I had an identical problem with the refrigerator outlet, but in that case, the neutral was discolored for about 4inches, fortunately the insulation was not hardened. After that I redid the whole house, using the screw terminals and never again had a problem even though aluminum wired. My friend’s home had copper wire but his refrigerator outlet stopped working. Again a “backstab” with the neutral wire blackened. In this case we had to saw out a section of dry wall to relocate the outlet as we had to cut off about 1 foot of cable to get to good insulation. My friend said he knew something was wrong for about 2 years, but was blaming the refrigerator.

When I took out the duplex after my first failure, I pried it apart to see why it failed. It was obvious that there is only a very small contact area between spring and wire. Small contact area equals high resistance. I don’t understand why these things are permitted.

In all cases, the neutral connection was the problem, wonder why, as it carries the same current as the “hot”?
 
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Old 01-29-04, 07:36 AM
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I wonder too why the neutral backstab fails so much more often than the hot backstab. I have no explanation. Perhaps it has something to do with the internal design of the receptacle.
 
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Old 01-29-04, 10:23 AM
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1Geniere-

From your post, I've decided that backstabbing is definitely not the way to go with aluminum wire. Fortunately, we don't have much of that (if any) around here.

I agree that a backstabbed connection has less contact area than connecting to a terminal, but I doubt if Underwriters Laboratories would list backstab fixtures if they weren't safe.
 
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Old 01-29-04, 05:14 PM
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I find it hard to believe that any electrician has not seen a backstab failure!
I must repair one a month.

I recently did a friend's modular, which is supposed to be factory checked and inspected for the finished wiring. We do the service, basement, well, bolier, etc.. He called saying the master bath lights were not working, never were. I said I wasn't even in the bathroom. Anyway, I checked the wiring diagram and noticed a bedroom on the same circuit. All the receptacles in the BR were out. I went to the first on the circuit and guess what...bad backstab. Brand new receptacle, done correctly.
 
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Old 01-29-04, 10:21 PM
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Same here, Ive seen tons of them.. some were scary! Most times it would be somebody complaining because the TV didnt work until "that one plug was jiggled". I did have one receptacle that powered an airconditioner in this place. The guy was old and all he knew was that the AC died and to cut the breaker off. I came in and simply unplugged the AC unit... the receptacle was still there.. or so it seemed. So I went back to turn the breaker on. When I got back to the receptacle and looked at it I noticed it glowing. So I ran back and turned the breaker off. The remains of the receptacle crumbled into my hands as removed what was left of the yoke. There, barely hanging to the remains of the wire was the backstab "spring" and the remaining side of the receptacle.

That was my worst one. Id say if Id kept any I would have a bucket full of melted backstabs around!

The weird thing though is that I have only seen this on #12 backstabs. I never have had a #14 backstab. Granted most around here dont use 14 and 14 is the only size permitted on a backstabbed receptacle. Maybe Ill just have to give those some time. Even though Ive never seen one doesnt mean I condone its use! I'll never use a backstab when there are screws present.

Also I think years down the road all these boards will be filled with posts about the "wago" quick connectors too. Its basically the same thing!
 
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Old 03-09-14, 03:00 PM
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i have used the back stab outlet concoctions once for my computer area worked fine under a computer load for over 5 years but when i needed to plug in a space heater during the winter they failed within a 3 months under that load if those were done using the screw terminals i would have expected the outlet to last 2 years or more under that load but then the front of the outlet fails instead of the back the only way around this that i found is to use heavier wire and an big 240 40 amp twist outlet the backstab connection is not for heavy load and even the screws are not for constant heavy loads
 
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