Is a loop required under a receptacle screw?

[Delta_Dave]

I'm having a debate with one of my workers. He claims there is no requirement or code requiring that a loop be put under the neutral or hot screws. He claims it's OK to put the striped wire on the left side of the screw with no loop and tighten it down. We always put a loop under screw connections. He claims if it loosens over the years it's better because it will become disconnected. I claim a loop makes a better long-term connection. Is there any code or requirement for a loop?

 

[tom baker]

What do the device instructions state?

 

[LarryFine]

The loop is definitely more secure, has greater contact area, and won't bend the screw to one side.

If there is a pressure plate, especially with stranded conductors, then it's less critical.

 

[tthh]

Even if the instructions said a loop wasn't required, that is the right thing to do.

 

[Dennis Alwon]

AFAIK there is no code issue however, you probably will find out that pushing the receptacle back may make the wire pop out.

 

[rc/retired]

Funny old world isn't it? Do we use the stab ins for receptacle outlets and switches or do we loop the wires around screws? Or neither?
What to do?

Ron

 

[tthh]

Funny old world isn't it? Do we use the stab ins for receptacle outlets and switches or do we loop the wires around screws? Or neither?
What to do?

Ron

Back wire is the best of both worlds

 

[jaggedben]

What do the device instructions state?

While I support this sentiment, people sell switches and receptacles loose in bins with no instructions.

 

[SSDriver]

While I support this sentiment, people sell switches and receptacles loose in bins with no instructions.

Yes, and for the cost savings of buying those devices it's up to you to install them per the instructions/listing that you may have to lookup and download. Or just wrap the screw and move on.

 

[Besoeker3]

FWIW we use crimp pins and coloured ferrules. Works for us.

 

[kec]

He claims if it loosens over the years it's better because it will become disconnected.

So what if it loosens but stays in contact with the screw. Ask him if he has seen a loose wire under a load.

 

[synchro]

AFAIK there is no code issue however, you probably will find out that pushing the receptacle back may make the wire pop out.

Without a loop, I think a solid wire is likely to rotate on its axis under a screw when a receptacle is pushed back, and that could make the wire get loose and possibly pop out.
With the pressure plate type where the wire's end remains unbent, I think slightly flattening a solid wire with a pliers may help prevent it from rotating when a receptacle is pushed back. That's just a personal preference.

 

[hbiss]

You're asking for trouble. If the device only has a screw, you form a hook in the wire and tighten the screw down on it. If there is a pressure plate, instructions say either insert the straight conductor under the plate and tighten it down or put a hook under the screw.

Unless instructions say otherwise...

-Hal

 

[hbiss]

With the pressure plate type where the wire's end remains unbent, I think slightly flattening a solid wire with a pliers may help prevent it from rotating when a receptacle is pushed back.

If it rotates you haven't tightened it enough.

-Hal

 

[Dennis Alwon]

Without a loop, I think a solid wire is likely to rotate on its axis under a screw when a receptacle is pushed back, and that could make the wire get loose and possibly pop out.
With the pressure plate type where the wire's end remains unbent, I think slightly flattening a solid wire with a pliers may help prevent it from rotating when a receptacle is pushed back. That's just a personal preference.

I agree I stated that earlier. If I were an inspector I would turn it down based on mechanical strength or something of that nature. It can't be compliant.

 

[Dennis Alwon]

This is from an old thread from member M.D.

for Leviton Devices
Connect wires per WIRING DIAGRAM as follows:
NOTE: Side wire terminals accept up to #10 AWG
wire.
TO SIDE WIRE:
? Loop wires clockwise 3/4 turn around terminal
screws.
? Green or bare copper wall box wire (Ground)
to Green screw.
? Line 1 Black (Hot) wall box wire to Brass screw.
? Line 2 Black (Hot) wall box wire to remaining
Brass screw.
? White (Neutral 1) wall box wire to Silver screw.

 

[synchro]

I agree I stated that earlier. If I were an inspector I would turn it down based on mechanical strength or something of that nature. It can't be compliant.

I intended my post as a response that was affirming yours, but I forgot to quote it.

 

[roger]

The NECH has information and exhibits showing and explaining wire terminations from UL, Here is the text. There are two illustrations to accompany the text but I can not get them to paste


Installation Method
Exhibit 110.3 illustrates the following correct method of connection:

1. The freshly stripped end of the wire is wrapped two-thirds to
three-quarters of the distance around the wire-binding screw
post as shown in Step A. The loop is made so that rotation of
the screw during tightening will tend to wrap the wire around
the post rather than unwrap it.

2. The screw is tightened until the wire is snugly in contact with
the underside of the screw head and with the contact plate
on the wiring device as shown in Step B.

3. The screw is tightened an additional half-turn, thereby providing
a firm connection, as shown in Step C. When a
torque screwdriver is used, the screw is tightened to
12 inch-pounds.

4. The wires should be positioned behind the wiring device to
decrease the likelihood of the terminal screws loosening
when the device is positioned into the outlet box.

 

[Frank DuVal]

110.12 Electrical equipment (and a receptacle is equipment) shall be installed in a neat and workmanlike manner.

 

[Delta_Dave]

I agree, a loop is best practice. I see the Leviton online instructions say to make a 2/3 loop under the screw. However, does NEC or any code state that a loop under a screw is required?