Wiring Multiple 2 Gang Outlets Together (inline)


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Old 09-22-22, 01:55 PM
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Wiring Multiple 2 Gang Outlets Together (inline)

I'm not sure if I can explain this in a way to be clear.

In my new shop. I want mostly 2 gang outlet boxes on one circuit. I've never done this & I cant find even one video to show what I want (am doing). (For clarity, this is not for multiple tools/appliances at once but more for convenience.)

We'll call the 2 outlets in each box as A & B.
In the first 2 gang box:
Should I or can I, connect the first outlet (A) as normal with hot & neutral. Then use a jumper hot & neutral from outlet "A" to outlet "B". Then wire nut all the incoming, outgoing & one ground for each outlet together for a total of 4 ground wires in one wire nut.
Then run the outgoing 12/2 from "B" in the first 2 gang box, to "A" in the 2nd 2 gang box & repeat.

Is this the correct way to do that?

One 15 amp breaker with three or four 2 gang outlets with 12/2 Romex on each circuit.
 
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Old 09-22-22, 02:22 PM
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Sounds OK to me and that is how I would do it except you can probably wrap the incoming ground wire on receptacle A and leave a tail to be nutted to a tail from a similar connection of the outgoing ground on receptacle B. If the box is metal, one of the ground wires should be wrapped around a grounding screw to the box or a pigtail to the nutted bundle.

Not more than one wire under any terminal or ground screw.

The only possible objection to daisy chaining A & B might be that a failure of either will affect the downstream receptacles. Pigtails and wire nutting all current carrying connections (incoming, A, B, outgoing) provides a direct through connection that does not depend on the integrity of a single receptacle. I do not think pigtails adds to the number of wires per box cubic inches but the actual space may get crowded.

EDIT: It just occurred to me that there may be a code restriction to daisy chaining the neutral. For just the reason I stated above about a device failure interrupting continuity.
 

Last edited by 2john02458; 09-22-22 at 02:33 PM. Reason: neutral issue
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Old 09-22-22, 02:38 PM
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Sounds OK to me and that is how I would do it except you can probably wrap the incoming ground wire on receptacle A and leave a tail to be nutted to a tail from a similar connection of the outgoing ground on receptacle B.
OK great. Didn't think about that but I've seen it done so I know what you're saying.

​​​​​​​If the box is metal, one of the ground wires should be wrapped around a grounding screw to the box or a pigtail to the nutted bundle.
To clarify, it's not metal. I am using all plastic boxes.

​​​​​​​Not more than one wire under any terminal or ground screw.
Agreed.

​​​​​​​The only possible objection to daisy chaining A & B might be that a failure of either will affect the downstream receptacles. Pigtails and wire nutting all current carrying connections (incoming, A, B, outgoing) provides a direct through connection that does not depend on the integrity of a single receptacle. I do not think pigtails adds to the number of wires per box cubic inches but the actual space may get crowded.
Good advice. I think I'll refrain from all that excessive pig-tailing. LOL

​​​​​​​Thanks for your valued input & advice.
 
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Old 09-22-22, 05:05 PM
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You need to find out if daisy chain is ok for neutral. Maybe one of the experts familiar with the code will chime in.
 
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Old 09-22-22, 07:24 PM
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Best practice would be to do as 2John described. Wire nut the incoming wires and outgoing wires along with three pigtails (hot, neutral, ground) for each receptacle. However, the way you describe is allowable. But a couple points:

If you are using 15 amp breakers you only need 14 ga romex. IIWM, I'd use 20 amp breakers and 12ga romex for a workshop.

You need to pay attention to the volume of the plastic boxes you use. 2 gang boxes come in different depths which translates to different interior volume. The NEC has rules about what volume box is require based on how many devices (in your case receptacles) are in the box, how many wires enter, leave, and pass through the box, and how many pigtails (jumpers) are inside the box. If you search for "online box fill calculator" you will find calculators that will let you calculate the necessary box volume needed. All boxes sold today will have the volume stamped into the box. Regardless of what the calculator says, you will do yourself a favor by buying the highest volume box you can (= or > than the calc tells you) because it makes wiring *way* easier.
 
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Old 09-22-22, 07:38 PM
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I do not like to feed through devices, I like to pigtail the devices to the incoming and outgoing wires going through the boxes using wirenuts. This way you are not relying on the devices for your connection.

For fourplex/double duplex boxes I will take a long piece of wire and connect the hot, neutral, and ground wires to one device, then remove a small piece of the insulation in the middle of the wires and then loop the wire around each corresponding screws of the other device, leaving enough wire to connect to the incoming and outgoing wires.

If this doesn't make sense maybe I can make a video for you.
 
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Old 09-23-22, 02:27 AM
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I do not like to feed through devices, I like to pigtail the devices to the incoming and outgoing wires going through the boxes using wirenuts. This way you are not relying on the devices for your connection.
I absolutely agree with Tolyn Ironhand. This way if a receptacle fails for any reason the failed receptacle is isolated and you can still use the receptacles downline of the failed one. Running them daisy chained in "series" if a receptacle fails then all of the ones downline would more than likely fail.
 
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Old 09-23-22, 04:54 AM
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I wont quote everyone but based on all the same advice from everyone, I'll pigtail everything as noted.

I thought about some 20 amp breakers but just decided to go with 15's. I'm still on my first long side and its going to be the "storage" side etc where tool boxes, nut & bolts etc will be. I may consider using 20 amp on the actual work side where the power tools & work bench etc will be. I know I'll need everything to be 20 amps on that line... breakers 12/2 wire & outlets.

I actually did buy the biggest boxes I could find. I at least had that foresight.

Tolyn, offering to make a video was a nice gesture but no need, I understand what yall are explaining. I appreciate the offer though.

AFJES, thanks for your input & supporting their points. Thats what I like to see... multiple people with the same view. I know its the right thing to do.

I appreciate everyone's input and advice.
 
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Old 09-23-22, 11:16 AM
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While 15A breakers on 12ga wire is code-acceptable, I'd personally consider it bad practice to do it this way. It would indicate to me that there may be 14ga wire somewhere on the circuit and just not be a 'clean' install.

I'd much rather use 20A breakers on 12ga wiring to keep it consistent.

Also, don't forget GFI protection!
 
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Old 09-23-22, 11:35 AM
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One 15 amp breaker with three or four 2 gang outlets with 12/2 Romex on each circuit.
Remember outlets (actually they are called "receptacles") do not consume power so technically you can connect 50 receptacles to a circuit. It is what is plugged in and consuming power that matters.

The next thing that matters on the circuit is what is plugged in and the amps it is drawing so that you have the proper rated gauge wire/s and over current protection device (breaker) to protect the wire/s (circuit) and what you have plugged in and is consuming power.

So give yourself a rule to look at when figuring how many circuits you need.

Simple Ohms Law
A 15amp circuit (breaker)
15 amps times 120 volts = 1800 watts
This means the absolute most you can have plugged in a using at one time is 1800 watts on that circuit.

Simple Ohms Law
A 20amp circuit (breaker)
20 amps times 120 volts = 2400 watts
This means the absolute most you can have plugged in a using at one time is 2400 watts on that circuit.

How do you know how many watts you are using on the circuit.
Simple Ohms Law again
Your tool says it uses 8 amps and 120volts
8 times 120 = 960 watts
Your tool says it uses 960 watts and 120 volts
960 divided by 120 = 8
Simple right?

This is a basic guide. Other rules/guides apply for other things like "continuous loads" etc which you really don't have to worry about with your circuit application.
Glad you decided to wire nut jumpers to each receptacle. This may save you a lot of time in the future. When ever I wired receptacles for a renovation etc I always asked the customer if they wanted to wire them this way especially landlords. This way if one receptacle fails only that receptacle is fails and not all of the ones downline from it which may also include lights on the circuit. You get less calls from the tenants this way complaining that they have so many receptacles and lights that are dead.
 
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Old 09-23-22, 04:04 PM
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Yes Sir, thanks for taking the time to add these tips. While this is my third building/shop to wire, I'd like to think I know the basics, some of what you posted was a refresher in my limited electrical knowledge. My electrical ability isn't always to code (& most of the time it takes me 3 try's & 3 hrs to do what yall do in 3 minutes) but the basics are there & so far, over about 22 years, nothing has shorted out or burned down.

My personality is about going beyond rather than skimping out cheaply. My old dear departed co-firefighter brother once said; "It don't cost but a little more to go first class." I've taken that to heart on many occasions.

To give a little more input on this shop just FYI, its a piddling shop. If a lawn more or 4 wheeler or a pocket knife needs a little maintenance work, I'll have a place for piddling. While I have collected 4 or 5 bench grinders, chop saw and along with a couple of 7500 watt A/C's in the shop, most everything else is light weight hand tools pulling lower amps. Additionally, I usually only use a couple of things at a time. (The biggest load in that shop is on my brain trying to remember why I have that hammer in my hand)

The main reason I have so many outlets is for convenience, not item/tool quantity. No extension cords for me or at least only one or two. I like receptacles.. a lot of them. I want one right there all the time.... handy. I'll have 6 in the ceiling for LED lights etc. Then additionally a couple of hanging reels.

The biggest thing that messes with most of my friends & advisors on my construction projects is the amount of circuits I run when doing a project like this. Its a 32 X 16 & I have a 40 space main panel and it'll pretty much be full when I am finished.
This references the concern about over loading a circuit. I prefer to have over, rather than wish down the road. I say do it now while its open and accessible. Each A/C is on its own dedicated circuit. They are both 120V. I am also adding a 220 receptacle incase I want to replace it with a 220 later on. The 230 amp stick welder is on a single circuit. Chop saw will be on a single 20 amp circuit.
I am only running one ceiling fan & two LED shop lights per circuit. I'll have 3 circuits for the lights & ceiling fans. I know... I know...

But you know what, when something fails on one of those circuits.... when a ceiling fan quits & I need to change it out, I'll have 2 more circuits - 4 lights & 2 ceiling fans still running when I turn off the one with the problem. I wont be holding a flash light in my teeth to see how to change a ceiling fan.

So, is it over kill? Yes, but its the way I want it and...... "It don't cost but a little more to go first class!"
And I wont be wishing down the road... Do it now & its always there. If I need it, its there.

Again, thanks for all your tips above. Its very much appreciated.
 
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Old 09-23-22, 06:23 PM
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I also agree. If you are running 12/2 cable why not use 20 amp breakers? They cost the same.

​​​​​​​I know I'll need everything to be 20 amps on that line... breakers 12/2 wire & outlets
You do not need to use 20 amp outlets on a 20 amp circuit. The internal guts on 15 and 20-amp devices are the same. It is very rare that you need a 20 amp configuration for general use circuits.
 
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Old 09-23-22, 10:36 PM
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You are welcome.

Since it is a shop what you may want to do is purchase instead of the run-of-the-mill cheap receptacles get yourself some good commercial grade receptacles HERE that will last much longer and are more heavy duty. Also these are self-grounding receptacles (see the small metal tab on the bottom strap). Make sure your metal box is grounded and just install without needing a jumper ground wire to the receptacles. If using a plastic box then you do need the jumper ground wire to the receptacle.

My personality is about going beyond rather than skimping out cheaply
Go with 20amp breakers since you are running 12/2 anyway. This is not going beyond but just matching the capacity of the 12/2. As stated if you are going with 15amp breakers for sure then you can use 14/2 but gong that extra mile with 20amp 12/2 and good 20amp commercial grade receptacles you can't go wrong.
 
 

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