Daisy chaining outlets

[racraft]

What is the proper way to daisy chain duplex outlets?

Based on what I have read here, I am under the impression it is not allowed by code to connect the incoming wires from the previous outlet (or panel) to one screw terminal, and then connect the outgoing wire to the other screw terminal. I have been led to believe that the wires must be wire-nutted to a third pigtail wire which is connected to the one of the screw terminals.

I ask because the electrician doing the wiring for my basement remodeling did the latter. Is this a code violation? Is this unsafe in any manner?

 

[bphgravity]

Re: Daisy chaining outlets

Receptacle outlets should be wired in a manner that if one is removed from service, the rest down line will not go dead. By using the two terminals on the receptacle for connection, this cannot be accomplished. It is always best to make wiring connections independent of devices and equipment. The splicing and pig-tailing is the better way. The same holds for looping switch supplies.

 

[don_resqcapt19]

Re: Daisy chaining outlets

While what bp said is good practice, it is not a code requirement. The only code requirement to pigtail is for the grounded conductor of a multiwire branch circuit. See 300.13(B).
Don

 

[bryonb]

Re: Daisy chaining outlets

I agree that pig-tailing is the better method, but as far as this installation being a code violation, it depends.
300.13(B) says that the continuity of the grounded conductor in a multiwire branch circuit shall not depend on device connections where the removal of such devices would interrupt the continuity. If the outlets are not part of a multiwire circuit there is no violation. If it is a MW circuit, you can, in my opinion, "loop" the neutral around the screw without cutting it to meet the requirement of this article.

It has been my experience that splicing and pigtailing is just as quick as having to strip, bend and tighten four different wires on four different screw terminals.

 

[electricmanscott]

Re: Daisy chaining outlets

What are there two sets of screws for? Either method is perfectly acceptable.

 

[stamcon]

Re: Daisy chaining outlets

You need the two screws for spilt wiring the receptacle. Two separate circuits or half switched/half hot.

 

[daverz]

Re: Daisy chaining outlets

It is perfectly acceptable to wire receptactles so that the line is connected to one post and the load to the other. Receptacles are designed and intended to be installed this way.

The only time it is not acceptable is in the case of a multi-wire branch-circuit.

300.13(B) states that "In multiwire branch circuits, the continuity of a grounded conductor shall not depend on devide connections.." This means that at the first receptacle (the one at the "homerun") the grounded (neutral) conductors must be pigtailed. Downstream from there, pigtailing is not required.

 

[bphgravity]

Re: Daisy chaining outlets

It may be acceptable, but I don't think it is a good practice. When you use the recepatcle as the junction point, the loads downstream will be fed through at the receptacle terminals. Really not a problem considering the receptacles are rated to the OCD of the circuit, but I would rather put my juctions and loads independent of a device. Aticle 110.12 is open to the AHJ and you never know.

 

[racraft]

Re: Daisy chaining outlets

Does it change the picture if the circuit is a 20 amp circuit (20 amp breaker, 12 gauge wire) with 15 amp duplex outlets?

Suppose that two separate downstream duplex outlets each have loads drawing 8 amps. This means that 16 amps will be drawn through all upstream outlets. I see this as a potential problem, or has the outlet manufacturer taken this possibility into consideration when designing the bridge connection between the screw terminals?

 

[bryonb]

Re: Daisy chaining outlets

Racraft,
That is an excellent point. I called Levitons Techline to ask this question and ended the conversation more confused that before I called. They told me that the screw terminals on their 15 amp duplex receptacles are capable on handling 20 amps. I asked where that information is listed and he said that it doesn't have to be listed. "But wait," I said, "it does say that this device is listed and rated for 15 amps (insert dramatic, confused voice here)." He told me that since the code book does not say that the screw terminals have to be rated, there is no listed rating for such and the UL listing only adresses the "face" of the recepacle.

 

[iwire]

Re: Daisy chaining outlets

2002 NEC Table 210.21(B)(3) Allows 15 amp receptacles on 20 amp circuits

However 210.21(B)(1) restricts single receptacles to be rated the same as the overcurrent.

Leviton

[ March 11, 2003, 01:44 PM: Message edited by: iwire ]

 

[luke warmwater]

Re: Daisy chaining outlets

I agree that it is acceptable practice to feed through at the device, but did you ever notice that on a new residential grade duplex, both screws on each side are normally backed out, and on new spec grade devices, usually only one screw is backed out on each side?

 

[alex399]

Re: Daisy chaining outlets

I read where someone measured the dimensions of the tab on a 15amp recep and found it to be just slightly under the dimensions of #14 wire... So wiring through the tab on a 20 amp circuit isn't smart, and should be illegal.. (For a 15 amp circuit, I guess it's fine, but I pigtail anyway)

 

[iwire]

Re: Daisy chaining outlets

Originally posted by alex399:
I read where someone measured the dimensions of the tab on a 15amp recep and found it to be just slightly under the dimensions of #14 wire...

Alex, Trying to apply the NEC to manufactured devices or appliances that are UL listed will usually not work out. But if you must 310.16 rates #14awg at 20 amps minimum, it is 240.4(D) that has us use 15 amp breakers

 

[russellroberts]

Re: Daisy chaining outlets

My question is,even if you pigtail,and you land your wires on the top screws on a 20a ckt.Someone plugs a 16a load in the bottom half of the recep,you're still depending on the tab. Granted it's only on the one recep,but the tab still comes into play.