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Stephen Tashiro
10-30-2019, 1:05 PM
An AZ electrician told a friend of mine that if he (the electrician) replaces receptacles and switches in my friend's AZ house that code requires him to use the push-in "stab" connections on the receptacles and switches instead of the screw terminals. This is a special situation in that the electrician would be doing "pig tailing" to connect the aluminum household wiring to copper wire before connecting the copper wires to the receptacles and switches.

Anyone know if this statement is correct in AZ? - or perhaps only in the Phoenix area? If it's true, what would be the reason for such a code?

Jim Becker
10-30-2019, 1:16 PM
I can't answer your code question, but higher quality receptacles with provisions for back-wiring do so with a screw from the side to secure them tightly, unlike the lower cost economy products that rely on something spring-loaded or barbed.

Jim Koepke
10-30-2019, 2:01 PM
Like Jim, my knowledge of code is very limited.

The main point here may be this:


This is a special situation in that the electrician would be doing "pig tailing" to connect the aluminum household wiring to copper wire before connecting the copper wires to the receptacles and switches.

My understanding of problems in wiring with aluminum is the aluminum expands and contracts more than coper with heat and cold caused by the flow of electrical flow. This may have been the cause of wiring performance failure and possibly fires. A spring-loaded connector may be better handling thermal expansion and contractions during use.

Once again, this is just off the top of my head thinking about this. If one really wanted to know, my suggestion is to consult your favorite search page.

jtk

Paul F Franklin
10-30-2019, 2:22 PM
This sounds very suspect to me. Pigtailing aluminum wiring is an accepted technique for improving the safety of aluminum house wiring. The aluminum wiring is connected to a short piece of copper wire using a connector approved for this purpose. The connector is designed to avoid the loosening and corrosion issues often seen with aluminum wiring. Then the copper wire is connected to the switch or receptacle in the normal fashion. There is no reason to put any special requirements on the copper wire to device connection. It makes no sense (not that that rules out it being in the code!) to require the end of the copper wire to be back-stabbed into the device. I would suggest a call to a local inspector as they would be the authority. My suspicion would be the electrician is trying to save a minute or two per device by using the backstabbed connection. As Jim points out, back-wired receptacles are available that use a screw but don't require hooking the wire around the screw. This is a desirable method but the devices tend to be a fair amount more expensive and so often aren't used when cost is a factor.

Frank Pratt
10-30-2019, 3:15 PM
Those push-in connections (as opposed to back or side wired) are the work of the devil. If I had a dollar for every on of those that I've replaced, I'd be able to afford a nicer shop.

418528

I keep this little beauty on my desk to show new employees when I read the riot act on push-in terminals. This is not the worst example I've seen, but just about. But most just fail to conduct, or worse, do it intermittently so it takes forever to find the problem.

The bureaucratic rationale behind this lunacy is that a device that intrinsically applies the correct design pressure to a connection is going to be more failure resistant that one where the tightening torque is up to whomever is holding the screwdriver. And it is valid reasoning. But in the real world, a $1 switch or receptacle is not going to have the precision engineering & manufacturing needed to make this theory work

They've been making these cursed things for at least 40 or 50 years & they still haven't figured out how to get it right.

End rant.

Kev Williams
10-30-2019, 4:18 PM
...even I know that a few sq. mm of screw head surface clamping the wire is going flow current better than the edge of a semi-spring loaded brass razor blade...

Edward Dyas
10-30-2019, 4:32 PM
An AZ electrician told a friend of mine that if he (the electrician) replaces receptacles and switches in my friend's AZ house that code requires him to use the push-in "stab" connections on the receptacles and switches instead of the screw terminals. This is a special situation in that the electrician would be doing "pig tailing" to connect the aluminum household wiring to copper wire before connecting the copper wires to the receptacles and switches.

Anyone know if this statement is correct in AZ? - or perhaps only in the Phoenix area? If it's true, what would be the reason for such a code?Sounds fishy to me. Any electricians I know look down on the stab connections. I find it hard to believe it would be code there. The pigtail would be correct for aluminum wire.

Call the building code office and ask them about the stab connections. The electrician may be telling you a fairy tail to save themselves labor.

Jim Koepke
10-30-2019, 6:21 PM
Okay, here is something to prove my knowledge on the subject is even less than previously stated:


(Aluminum has) greater thermal expansion and contraction. Even more than copper, aluminum expands and contracts with changes in temperature. Over time, this process will cause connections between the wire and the device to degrade. For this reason, aluminum wires should never be inserted into the “stab,” “bayonet” or “push-in” type terminations found on the back of many light switches and outlets.
(Aluminum has) excessive vibration. Electrical current vibrates as it passes through wiring. This vibration is more extreme in aluminum than it is in copper, and, as time passes, it can cause connections to loosen.

This is from > https://www.nachi.org/aluminum-wiring.htm <

It also mentions aluminum wiring may void fire insurance in some cases.

My advice would be to find a different electrician.

jtk

Roger Feeley
10-31-2019, 2:43 PM
I had a bunch of thos stab connectors in my old basement shop. When I ripped all that out to sell the house, I bet 10% of the connections were loose. It’s a miracle I didn’t burn my house down. My new basement shop is still back wired, but with the screw clamps.

Also the springy stab connectors are limited to 14ga wire. I used that only for lights and those are all LEDs. All the tool outlets are 12ga.