Receptacle stabs

[goldstar]

I keep running into this problem over and over again. A customer calls and says that there is no power in one of their rooms but all breakers are on. I know what the problem is just from the conversation. I get to the house and begin removing receptacles and low and behold all the wires are "stabbed" into the backs of the receptacles. And, as if that weren't bad enough, in some cases there are wires attached to the same receptacle via the screw terminals. In most cases, where the stabs are used and there are only 4 wires (2 white & 2 black) the screw terminals are not even tightened down. If you're lucky you'll find the loose wire when you pull out the receptacle or find a burnt receptacle where the wires had become loose.

I had a "go around" with someone from EC Magazine on this subject a while ago but somehow couldn't get my point across. They kept indicating that the stabs are an approved method of attachment. My gripe with this wiring method is that over time the captive hardware part of these stab connections becomes loose due to heat from loads attached. If you cascade or daisy-chain a number of receptacles (lets say 8) and use this wiring method, the load for the enrire circuit is borne by the first receptacle of that circuit. Some might argue that they run into this situation even with the screw-down method of attachment but I've got to believe that the occurrances of interrupted circuits are far less than the stab method. I also think that usnig the receptacle stab method is a fire hazard and should be addressed by the Code panel.

Again, just my opinion.

[ May 02, 2003, 05:54 AM: Message edited by: goldstar ]

 

[electricmanscott]

Re: Receptacle stabs

I agree. I can't think of a service call in a residence that is more common than you describe. I don't understand why this is allowed.

 

[bphgravity]

Re: Receptacle stabs

I also find this to be a consistant problem on service calls. The problem I feel has to with the "no maintenance" attitude towards electricity. Since most people don't understand how electricity works and how important terminations are, the electrical system of a house hardly gets any attention until there is a failure.
In my opinion, homes need preventative maintenance just as much as an industrial warehouse. No one wants to pay for it, so it never gets done. Every house I have ever wired comes with a yealy inspection and maintenance schedule. I open all devices and torque all loadcenter terminations. I check the GES, and all other equipment. If people would start treating their homes like their cars, and get them maintianed every once and awhile, most of these problems would be detected and prevented.

 

[don_resqcapt19]

Re: Receptacle stabs

Bryan,

... and torque all loadcenter terminations.

Why?
Don

 

[bphgravity]

Re: Receptacle stabs

Why not?
I don't know who or why someone else has been inside the panel since my last check. I have had occasions were circuits were added and connections had been changed and not properly torqued. Natural vibrations from garge doors opening and closing seem to have an effect on terminal screws over time. I have had an occasion when a manufacturing defect that did not show up at the time of installation become apparent to me a year later. I have instances of bug and animal infiltration that needed to be cleaned and sealed off. The list of possibilities is endless. So why not open of the panel and ensure all is well?
I am an electrician that believes that a current carrying conductor is a moving part due to the effects of heat and cooling of terminals over time. Preventative maintenance is for the purpose of prevention. You can't prevent anything if you don't look at it.

 

[electricmanscott]

Re: Receptacle stabs

Exactlly how do you perform maintenance on a backwired receptacle? I was under the impression that tourque ratings are for the intial installtion only. Yearly maintenance schedule? Do you do this for free? Or is this something you reccomend?

 

[bphgravity]

Re: Receptacle stabs

The maintenance I perform on a back wired receptacle is simply pulling out the device and ensuring the connection is still tight and secure. If the receptacle is not back wired, I check the screw terminals.
In the case of new construction, I usually contract an inspection of the entire electrical system just before my work guarantee is up. I then make a suggestion for a continuation of the yearly inspection for a fee.
I'm not as concerned with the actual after-installation torque values as much as I am just tightening loose connections.
I also work with several realtors in my community that hire me to make this inspection after each tenant cycle.
I has been a very successful endevour for my business that homeowners and the realtors to appreciate greatly.

[ May 01, 2003, 01:14 PM: Message edited by: bphgravity ]

 

[don_resqcapt19]

Re: Receptacle stabs

Bryan,
I have been taught that a wire termination should never be retorqued. The connection will relax over time, but this has been accounted for in the original torque specification. If there is evidence of a problem at the connection, the wire should be cut back and reterminated, not retourqued.
don

 

[noxx]

Re: Receptacle stabs

I still don't understand how backwiring of receps is allowed, it's a huge cause of open circuits, and with any serious load it's a near surety that metal fatigue will cause a connection to fail, and like as not burn some wire along with it.

I always recommend replacing these with sidewired receps, properly pigtailed. When receps are wired properly, I rarely if ever see connection failures even in very old installations.

-Noxx

 

[bphgravity]

Re: Receptacle stabs

Don,
What would be the reasoning behind not retorquing a terminal? Now I am not talking over-torquing. I simply mean going in checking that all connections are snug. Its more of a feel thing than a value thing as I stated in my last post. Do you have some listing requirments or other data that shows terminal tightening to be an improper procedure? I agree that problem conections should be completely redone, but should I NEVER touch a terminal ever again for the life of the equipment?

Thanks, Bryan

[ May 01, 2003, 01:46 PM: Message edited by: bphgravity ]

 

[don_resqcapt19]

Re: Receptacle stabs

Bryan,
What I was taught, is that if you go back and retorque a connection, you are actually over torqueing it. I don't know if it really applies to the smaller branch circuit conductors, but all conductors exhibit "cold flow" when under pressure from the termination screw. This "cold flow" was taken into account when the manufacturer set the torque spec. The torque spec also takes into account the expansion and contraction of the conductor based on the temperature. When you add additional torque at a later date you increase the cold flow. You have also increased the pressure over that in the original design. This can result in excessive cold flow the next time that the conductor heats up under load. This is turn will result in a higher resistance connection when the conductor cools off. Now a small load will create even more heat because of the increased resistance. This process can lead to connection failure.
Note: I do not have documents to back this up and there are a number of people on both sides of this issue.
Don

 

[bphgravity]

Re: Receptacle stabs

Thanks Don, I appreciate your viewpoint and information.

Bryan

 

[tshea]

Re: Receptacle stabs

I actually like the back-wired outlets! I've made quite a bit of profit out of the lazy wiremen.
It takes a couple more minutes to use the screws or pigtail the wires then back-stab than to just jam the wires and go.

I have taught the more handy homeowners how to re-make their receptacle connections. In fact I even received a $50 check from one with a thank-you note saying it was an easy job to do and promised to call me for everything else.
A little customer service can go a long way.

I assume some of you carry a torque screw driver in your pouch when installing #14 AWG under screws?
I used to have one for the panels until the local inspector went into the box and "checked" the tightness of the screw terminals. He said he was looking for any loose connections. I told him I was throwing my torque screwdriver away because if he was going to use his "calibrated torque elbow" I didn't need to use my screwdriver. He quit "screwing" around after that!

 

[don_resqcapt19]

Re: Receptacle stabs

Bryan,
Here is one link, but it has no supporting details. Here is another, but again not a lot of detail.
Don

[ May 01, 2003, 05:37 PM: Message edited by: don_resqcapt19 ]

 

[gregoryelectricinc]

Re: Receptacle stabs

I agree, back-wiring should be outlawed!!!!!! It takes very little time to pigtail a box (even a resi box) Personal service call experience proved to me that with an AFCI breaker, a heavy load (such as a dirt devil 12 amp vacuum) WILL trip the AFCI breaker. As far as the connection failures, I will say that after the holes were made to accept only # 14 wire the failures do seem to be i little less frequent.

 

[luke warmwater]

Re: Receptacle stabs

Did you ever notice while repairing a backwired device, that the method (by design) nicks the conductor. Isn't this what we are trying not to do when we strip it?
The first contractor that I worked for said anyone caught backwiring devices would be fired. Alot of service calls ended the practice.
My company wraps all terminations and has never had a call back related to this. We have gotten service calls where the problem was backwired related. Mostly by tract home contractors who's profit margin is so low, they steal every second they can.

 

[frenchelectrican]

Re: Receptacle stabs

i going to join this bandwagon about backwireing the devices and myself i really dont like it at all my self and other electrican ( my freind ) really detest it ... because alot of back wire most percentage have #14 wire there and few time i can smell it and some case i can actally hear it . sound like crackling sound and i knew what it is was and i remove one outlet and sure enough it show pretty good flash on us grrrrrr anyway i will cut to chase here really i wish all other electrican and inspecter to work together to ban the back stabbing device and i have alot of service call with moible home with alot of back stabbing device THAT incuding switches also !!!!and i end up replace almost all the outlets and switches devices to screw type and never get anymore call back i did read the nec code do allow that the #14 to be backstabbing but i really hate it myself sometime the wire can be bare just one spot and the ground wire or netural wire can short it out or else


merci marc

 

[hurk27]

Re: Receptacle stabs

Ideal just came out with these type of wire connectors I call them snake teeth wire connectors and they look like they will have the same problems. I have back-wired but the circuit is always pig-tailed at each connection. this will eliminate most of the failures. but I have seen many problems most because of moisture or dampness in the walls criodes the terminals.

 

[goldstar]

Re: Receptacle stabs

Thank you all for your replies on this sore subject. I was beginning to think that I was the only one that disliked the back wiring feature.


Bryan,

Great idea with the maint. & insp. schedule, but I don't know how you sell it ? Competition is usually so tough that to include it only serves to reduce your profits for the job. Do you actually go through the entire house and remove every receptacle ?

Noxx,

Pigtailing is a great idea also but,if you go through the trouble of pigtailing the wires at each receptacle location you've already lost the benefit of the time saving stab connection feature of the receptacle. Why bother back wiring the receptacle ? At that point you might as well screw down the wiring.

Luke,

You're right on the money with the tract builders. Most of these types of service calls that I've come across were in homes built by tract builders.

By the way, I don't know if any one else has come across these receptacles but I've seen some in older homes that were back wire "only" (no screw terminals). Hope I'm not dating myself. :roll:

 

[jbfan74]

Re: Receptacle stabs

Goldstar, I found one of those backwire only outlets the other day. 1st one I've seen and hopefully the last!! Yes, backstabed outlets are a cash cow. But I have always thought that you could not use a device to carry the neutral current.
I know 300.13(B) States: for a multiwire circuit that the continuity of a grounded conductor shall not depend on device connections, such as lampholders, receptacles, and so forth where the removel of such devices would interrupt the continuity.
I always pigtail both hot an neutral and have one wire go to the screw. That way only one outlet would quit working and not the whole circuit.

On another note, a friend of mine just had a house built, and I went in after the sheetrock and look at the job the EC did. This is what I found on just a few of the switches and outlets.
1: Backstabbed switches with 14 wire with no 15 amp breakers in the panel. Also the screws where not run in.
2: The romex entering the boxes from the top, and the outer jacket extends to the bottom of the box before being stripped.
3: Receptacle on the back porch not labeled as gfci protected. Not sure where this outlet feeds from, unless fed from the front porch gfci. Hopefully not from the kitchen gfci.

This house failed inspection for the electrical for the following reason! 1 covers not in place, but my friend had removed them to paint. 2 not meter and disconnect. Why would you call for a final without having the meter in?

Just my rantings for today!
Keith