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Was wondering can I add two 14-50 outlets to one 50 amp breaker using 6/3 wire and connecting with wire nuts? Also, recommend PVC or liquid tight flex conduit? Will be in the garage.

I want to add two electric car chargers. Wire will come out of panel and to a junction box. From here, one 6/3 wire to one 14-50 outlet and another 6/3 wire to another 14-50 outlet. Is this ok to do? Only one charger will be in use at a time. I have seen some wire nuts that can accept two 6 gauge wires but not three, which is what I will need. Any ideas where I can find those?

Also, my HVAC guy gave me some leftover liquid tight so was thinking of using that but can also use PVC. Any recommendations?

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On 50A circuits, the rule is one breaker - one homerun - one outlet (NEC 210.23) The only exception is circuits which supply only cooking appliances (210.23C). If you want to use two devices on one circuit, unplug the one you're not using and plug in the one you are.

It may be legal to feed two outlets with 2 breakers in a sub-panel. However I would think an inspector would look askew at a 50A breaker in the main panel serving two 50A breakers in a sub-panel.

It would probably be allowed if you had an interlock which allows only one breaker to be on at a time. Those are readily available, intended for generator interlocks. Just backfeed them - this is allowed unless the breakers are GFCI or AFCI. (and even if they are, move them around so they forward-feed.)


For wirenutting stuff that big, I use screw-down terminal blocks, they are more reliable.


I wouldn't worry about liquid-tight unless you actually expect water ingress.

I use metal conduit if the area is dry and unlikely to rust. It qualifies as a ground path, so pulling ground wires is unnecessary. As you may need to pull another set of 6 AWG... For 6 AWG wire, the hard max in 1" conduit is 6 wires. Sure, that's pullable - if you have an electrician's truck full of special pulling tools. But I don't, and I don't want to call that guy, so I wildly overbuild conduit. I use oversize conduit and lots of access points (junction boxes, conduit bodies) with no more than one 90 between them. At that point I can usually just push the wire through, without fishing.

If you're running conduit, don't use 6/3. That is sheathed multi-wire cable, informally called Romex, and it's stiff and miserable to pull through conduit. You are not allowed to remove the conductors from the sheath unless they have appropriate markings of their own, which they won't. The right stuff to use in conduit is stranded single-wire THHN (in dry areas) or THWN (in wet areas) - at 6 AWG size, most wire will be combo THHN/THWN.

See what your equipment requires. If you're in conduit, and it doesn't need neutral, don't put it in - you can always add it later. You'd use NEMA 6 instead of NEMA 14. Never use NEMA 10, it is obsolete.


Edit: I need more space to answer your comment.

From what they said on the website, Juicebox only needs 2 wires (plus ground). It is a modern style "switching" power supply which chops any input 110-250V into what it wants. What they call "red neutral" is only neutral in a 120V hookup, in 240V it is the other hot. So, no neutral. Saved you a wire. It is legal for Juicebox to wire their NEMA 14 plug with no neutral, I honestly have no idea if it's legal to not connect neutral on a NEMA 14 receptacle.

The website says two Juiceboxes have the intelligence to share a connection of limited current capacity. That is not unprecedented. Some washer-dryer combos are designed so the washer daisy-chains off the dryer, making it unnecessary to run a separate 120 service. The washer and dryer coordinate to not overload the 240V 30A circuit. They are UL listed to do that if connected according to the manufacturer instructions. Ditto Juicebox.

Over 50 amps, plugs and sockets are not allowed, you must hardwire the electrical connections. Check a voltage drop calculator on the web for the wire size. The site I used called out #3 Copper or #2 aluminum assuming a 75' run. However, you'd want to run aluminum anyway, because with large wires, metal content is a big part of the cost.**. When splicing this "big stuff" you use connection blocks with screws that typically use hex keys. They're about $10 each at your local electrical supply house. Grats, you graduated out of the big-box stores. Never look back.

Breakers protect wires, so the breaker must match "the thinnest wire", i.e. The wire in the circuit with the lowest ampacity. If that puts you between breaker sizes, you can go up to the next offered size, e.g. 80A. If you really want to run 100A wire, you can do that.

You have high aspirations and I would run conduit to match - no smaller than 1-1/2". Use larger boxes for working room... And think really hard about where your bends and/or conduit bodies are going to be. That big wire will be stiff.

**The infamous problems with aluminum wiring pertained to an alloy now outlawed, being used for small lamp and outlet wiring. That doesn't save any money, because in small wire, little of the cost is mineral value. It was done post-war because it was simply impossible for the surviving copper mines and smelters to satisfy post-war demand.

  • Thanks for the very detailed answer Harper. This is exactly the type of info I was looking for. And I'm going to have to go with a NEMA 14 as I'm purchasing one of these: emotorwerks.com/index.php/store-juicebox-ev-charging-stations I'm going with the 40 amp version but just for my knowledge, if I were to go with the 75 amp version, I would use a 100 amp breaker right? And that would require 2 gauge wire? – robk27 Jul 8 '16 at 14:20
  • You should be able to get 80A 2pole breakers...if the big boxes can't get them in, your local supply house certainly can. – ThreePhaseEel Jul 8 '16 at 22:16
  • I didn't get a notification for the edit you made to your answer so wanted to say thanks for the explanation Harper. And thanks for the comment Three Phase – robk27 Jul 14 '16 at 16:21
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    BTW -- what prohibits appropriately rated receptacles from being used on branch circuits upwards of 50A? (NEMA does define 60A devices, and above that, you can go to IEC standard pin and sleeve, which goes to 200A!) – ThreePhaseEel Aug 19 '18 at 2:23
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Q: can I add two 14-50 outlets to one 50 amp breaker

I read a lot of NEC Article 210, and focused on 210.23. I see no restriction on outlet count. I have to conclude: you can have two or more outlets or receptacles on one 50 amp breaker.

Everything else about Harper's answer is great advice (although I personally think going above 1 inch conduit is a bit much). I would have just commented on his answer, but I'm not allowed to comment.

The section of the NEC he references doesn't restrict the number of outlets on a 50 amp breaker. If you interpret the permissible load as a restriction on outlets, then no circuit breaker in the house can have more than one outlet on it and you have to ignore that the section is exclusively about multiple-outlet circuits.

National Electrical Code 2014

ARTICLE 210 Branch Circuits

210.23 Permissible Loads, Multiple-Outlet Branch Circuits. In no case shall the load exceed the branch-circuit ampere rating. A branch circuit supplying two or more outlets or receptacles shall supply only the loads specified according to its size as specified in 210.23(A) through (D) and as summarized in 210.24 and Table 210.24.

This section is actually about multiple outlet circuits and the load they are allowed to carry. So a 50 amp branch circuit must only carry a 50 amp load. This is ensured with a 50 amp circuit breaker.

210.23(C) 40- and 5-Ampere Branch Circuits. A 40- or 50-ampere branch circuit shall be permitted to supply cooking appliances that are fastened in place in any occupancy. In other than dwelling units, such circuits shall be permitted to supply fixed lighting units with heavy-duty lampholders, infrared heating units, or other utilization equipment.

So immediately, this says nothing about restricting outlets. In fact, it's actually defining what "fixed" or "fastened in place" loads can be wired to a multiple-outlet (210.23) 50 amp circuit (210.23(C)).

Let's look at the referenced table too.

enter image description here

Nothing about only 1 receptacle. It references back to 210.23(C) for permissable load, but that's not a discussion of how many outlets can be on the circuit.

Here's how I think about it: An outlet is not a load. It is only the potential for a load. 210.23(C) discusses connected electrical devices (lights and stoves) that put an actual, defined load on the circuit. That's why it doesn't mention outlets.

The circuit breaker protects the wire, outlets, and a device plugged in from over drawing current, over heating, and starting a fire. If the circuit breaker protects at 50 amps, then the wire and outlet must be rated to handle 50 amps. If two 50 amp devices are plugged into two 50 amp outlets on the same 50 amp CB, and those devices actually draw full 50 amps (rare) or above 25 amps each, and they are used at the same time, the CB will trip. That's it's job, to protect the wires. And presumably the user won't plug too many devices in again.

This is the design of almost every circuit in your house. (There are exceptions for the small-appliance branch circuits, outlined in 210.11(C)) Multiple outlets are on almost every breaker. If you plug in a bunch of space heaters, you will trip the breaker, but the wiring will be protected.

Having said all that, check with your local inspector.

While I'm here, I might as well complete the answer... although Harper's answer perfectly covers everything else.

Q: using 6/3 wire in conduit

Don't use 6/3. You need THHN for conduit.
3/4 inch EMT conduit can take four #6 AWG wires. Code requires no more than 40% fill of EMT (NEC Chapter 9), so you can calculate this yourself. I haven't looked up PVC, but if you use 1 inch PVC, you'll be good and it will be a lot easier to pull.

Another tip: The ground wire is not considered current carrying and can be smaller. (2014 NEC, Table 250.122) For a 50 amp circuit, you can use a #10 AWG THHN copper wire. This will save some money and make pulling much easier.

Q: I have seen some wire nuts that can accept two 6 gauge wires but not three, which is what I will need.

Use terminals blocks or "polaris connectors." Search for polaris connectors online, and you'll get a lot of results.

Q: recommend PVC or liquid tight flex conduit

I would use EMT. I've seen PVC sag a little with time, so I think EMT looks better. Also, you might be able to use it as the ground return (although I would feel safer with a ground wire).

If it must be PVC or liquid-tight, I would go with PVC, but I haven't used either in a long time. Liquid-tight might be more expensive to get fittings for and it might be more difficult to install.

  • I don't think this is a correct reading of the NEC -- 210.23 para 1 states that a multiple-outlet branch circuit can only supply loads of a nature specified in the appropriate subsection (A-D) of 210.23, which excludes all loads not specified in those subsections. – ThreePhaseEel Aug 2 '18 at 1:03
  • Do you know what isn't specified in the 50A section of 210.23 (A-D)? Outlets aren't specified. So by your logic, outlets would not be allowed on a 50A circuit. Never mind that the section is for "Multiple-Outlet Circuits" and that an outlet is not a load. The language actually talks about loads. Just to be sure, I checked with my AHJ and he agrees with the interpretation I presented. I also spoke to an electrician and did some extra online research to confirm. What version of the NEC are you reading? Maybe it's worded differently? – Krh3o Aug 19 '18 at 2:17
  • Are you certain your AHJ understood that this is in the dwelling unit context? 50A multi-outlet branch circuits are A-OK for any non-lighting load in a non-dwelling occupancy -- the restriction to cooking appliance loads only applies to dwelling units – ThreePhaseEel Aug 19 '18 at 2:27
  • Exactly, it's not concerned with outlets. Then you are saying 210.23 only allows cooking appliances fastened in place in dwelling units. In non-dwelling units, it allows fixed lighting units with heavy-duty lampholders, infrared heating units, or other utilization equipment. Where in there are 2 outlets not allowed? – Krh3o Aug 19 '18 at 2:30
  • It's a restriction on what's attached to the outlets -- note that I'm using the NEC sense of "outlet" here, rather than using it as a colloquial synonym for "receptacle" – ThreePhaseEel Aug 19 '18 at 2:32

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