Adding a 120V outlet near a 14-50 outlet. Can you tap off of it, or do you need a new wire?

[F14Scott]

Title says it all. I was thinking about what it would take to add a "guest" EV outlet on a post in my driveway. Naturally, 240V would be good, but having 120V there, also, would cover about everybody, plus I could use the 120V for home pressure washers or leaf blowers or whatever.

If I ran 4-wire to the 14-50, is it possible/safe/code to piggyback or tap into three of those wires for a 120V circuit? I'm thinking it would not be possible (for at least this reason): the single breaker for a 50 amp 14-50 would be too big for a 5-20 outlet. What if I ran 4-wires and a 20 amp breaker, used a 6-20 outlet (hot hot ground) for my 240V and used a 5-20 outlet (hot neutral ground) for my 120V?

But, maybe there is a way to do it that I don't know about. Otherwise, I guess one would run both a 4-wire and a 3-wire out to the post?

 

[davewill]

If you don't need the guest to plug in at the same time as you, why not just have them plug into your 14-50?

You can buy an adapter like this to plug in the occasional leaf blower: https://www.amazon.com/Conntek-Y1450520S-Generator-Y-Adapter-Connectors/dp/B00BHGXYRC You could also use it to plug in two 120v EVSEs, I suppose.

You can put in a small load center or one of the RV power boxes to handle both, but you can't just tap into the 14-50 for a permanent outlet.

https://www.amazon.com/GE-Unmetered-Circuit-Protected-Receptacles/dp/B00FI6TKK2

https://www.amazon.com/Square-Schneider-Electric-HOM24L70RBCP-4-Circuit/dp/B0002YSPPG

 

[pdx_m3s]

Electrically, sure it can be done. Everything is there in the 14-50 outlet box to run a standard 120v outlet. However, I doubt it is code-legal.

 

[F14Scott]

First, that Y-splitter is awesome. Didn't know such a thing existed.

So, that box with the two kinds of receptacles on it (the single 14-50 and the dual 5-20) is exactly what I was thinking to put on a small pole. I see it already has breakers aboard.

What would the items one would need to install that from the main panel? Size breaker? GFCI? Size wire and number of conductors? If I'm trenching it in, how deep? Conduit, I assume?

 

[pdx_m3s]

First, that Y-splitter is awesome. Didn't know such a thing existed.

So, that box with the two kinds of receptacles on it (the single 14-50 and the dual 5-20) is exactly what I was thinking to put on a small pole. I see it already has breakers aboard.

What would the items one would need to install that from the main panel? Size breaker? GFCI? Size wire and number of conductors? If I'm trenching it in, how deep? Conduit, I assume?

50 amp breaker in the main panel (not sure if GFCI breaker required for exterior outlet install), 6 AWG wire (red, black, white, green), conduit, unsure on trench depth, but would do at least 1.5 feet.

 

[brkaus]

That box already has a gfci on the 20a. I think if you put a gfci in the main panel you might have problems (occasional false trips).

You can always argue primary intent is for an RV and then I don’t think gfci is required on the 50a outlet.

 

[davewill]

Now you need a real electrician. It looks like you need #4 copper and a 70a breaker to feed the RV box. I would think you could do conduit or direct burial cable. For an RV, I'd think you could probably use #6 and a 60a breaker, but since you intend to use both circuits at the same time for EV charging, I think not.

 

[mswlogo]

First, that Y-splitter is awesome. Didn't know such a thing existed.

So, that box with the two kinds of receptacles on it (the single 14-50 and the dual 5-20) is exactly what I was thinking to put on a small pole. I see it already has breakers aboard.

What would the items one would need to install that from the main panel? Size breaker? GFCI? Size wire and number of conductors? If I'm trenching it in, how deep? Conduit, I assume?

That splitter wouldn't be so bad if it's fused properly. Maybe it is? If it is, I think it's pretty clean, if occasional use.
If not fused properly you might find one that is. Scary if it's not fused.

Make sure your Breaker back at the panel is GFCI type, especially an outdoor outlet, regardless of the 120V option.

 

[mswlogo]

geez louise, I found one. 15A. This has a non replaceable fuse.

Southwire Gas Range Adapter-9042SW8801 - The Home Depot

It is down right scary how much totally unsafe stuff is being sold out there. All Chinese crap with zero regulation.

Here is another with a breaker, little pricey but done right.

https://www.amazon.com/Adapter-Circuit-Breaker-Receptacle-Electrical/dp/B07PRHNDQR

 

[pdx_m3s]

Maybe OP can be a bit more specific as to what he hopes to achieve here.

Are you saying that you want a dedicated 14-50 outlet in the garage for yourself, and an additional charging outlet for another EV? Sounds like you also want the outdoor outlet to work with yard equipment? For your guest EV outlet, does it need to be 50 amps?

I think you may be over-complicating things by using an RV load box. If what you're after is having two EV charging outlets (one in garage and one outdoors that can also work with yard equipment), I would just run two separate circuits (one 50 amp for garage and one xxx-amp for whatever you choose for your guest outlet) and use an adapter for using yard equipment, that way you'll never be charging + using yard equipment on one circuit at the same time. Just make sure you use a NEMA 14-xx type outlet for your guest outlet, as those are 4-wire and carry both 120v and 240v + neutral and ground to run 120v electronics. FWIW, I chose 14-30 as I didn't have panel capacity for 14-50.

 

[ewoodrick]

No one really said it, but you don't want to add the 120V 15A to the same circuit. An overload on that plug won't trip the breaker, just weld and melt the thing. That's why the one box shown has breakers for both plugs.

The 14-50 splitter is very common and many RV owners have one, as that's a normal RV plug. Most camping stores have some.

 

[F14Scott]

Maybe OP can be a bit more specific as to what he hopes to achieve here.

Are you saying that you want a dedicated 14-50 outlet in the garage for yourself, and an additional charging outlet for another EV? Sounds like you also want the outdoor outlet to work with yard equipment? For your guest EV outlet, does it need to be 50 amps?

I think you may be over-complicating things by using an RV load box. If what you're after is having two EV charging outlets (one in garage and one outdoors that can also work with yard equipment), I would just run two separate circuits (one 50 amp for garage and one xxx-amp for whatever you choose for your guest outlet) and use an adapter for using yard equipment, that way you'll never be charging + using yard equipment on one circuit at the same time. Just make sure you use a NEMA 14-xx type outlet for your guest outlet, as those are 4-wire and carry both 120v and 240v + neutral and ground to run 120v electronics. FWIW, I chose 14-30 as I didn't have panel capacity for 14-50.

I have a wall connector in my garage, and if I were to get another car, I'd get a second wall connector on the same 60 amp breaker and have the two share.

I guess, in my mind, the gold standard for a driveway (or even "curb," wouldn't that be a luxurious upgrade) power unit would be a lockable box just like @davewill suggested, above, with the ability to charge at 50(down to 40)amps 240VAC AND run a 120V shop vac at the same time without worrying about tripping breakers. So 70 amps seems right. I'm not sure my 200 amp service would support 60 amps to my wall connector, 70 to this hypothetical station, and the rest of my house.

 

[pdx_m3s]

I have a wall connector in my garage, and if I were to get another car, I'd get a second wall connector on the same 60 amp breaker and have the two share.

I guess, in my mind, the gold standard for a driveway (or even "curb," wouldn't that be a luxurious upgrade) power unit would be a lockable box just like @davewill suggested, above, with the ability to charge at 50(down to 40)amps 240VAC AND run a 120V shop vac at the same time without worrying about tripping breakers. So 70 amps seems right. I'm not sure my 200 amp service would support 60 amps to my wall connector, 70 to this hypothetical station, and the rest of my house.

Thanks for clarifying. If it were me, I would simply run two separate circuits to a lockable box with two outlets. One 120/20 circuit with a 5-20 outlet and one 240/50 circuit with a 14-50 outlet. If you run out of panel capacity, consider a 30 amp EV circuit with a 14-30 outlet. You can run all these wires in conduit of sufficient size. There are tables available that tell you how many wires you can fit per diameter of conduit.

 

[F14Scott]

Thanks for clarifying. If it were me, I would simply run two separate circuits to a lockable box with two outlets. One 120/20 circuit with a 5-20 outlet and one 240/50 circuit with a 14-50 outlet. If you run out of panel capacity, consider a 30 amp EV circuit with a 14-30 outlet. You can run all these wires in conduit of sufficient size. There are tables available that tell you how many wires you can fit per diameter of conduit.

Great plan. Raises the question: what do the other EV brands use for their mobile connectors? I know a lot of them have 5-15 120V plugs, but how about for 240V? Anybody know? Or do they mostly rely on permanently mounted charger/connectors?

 

[brkaus]

Great plan. Raises the question: what do the other EV brands use for their mobile connectors? I know a lot of them have 5-15 120V plugs, but how about for 240V? Anybody know? Or do they mostly rely on permanently mounted charger/connectors?

The J1772 is the standard connector on most EVs. It can support a range of currents and tells the car how much to take. It’s electrically compatible with the Tesla connector, but different physically.

 

[pdx_m3s]

Great plan. Raises the question: what do the other EV brands use for their mobile connectors? I know a lot of them have 5-15 120V plugs, but how about for 240V? Anybody know? Or do they mostly rely on permanently mounted charger/connectors?

Most other EVs use a J1772 charging connector for the cable-to-car connection. The chargers themselves plug into a wide range of outlets, just like Tesla’s.

 

[MrMassTransit]

Great plan. Raises the question: what do the other EV brands use for their mobile connectors? I know a lot of them have 5-15 120V plugs, but how about for 240V? Anybody know? Or do they mostly rely on permanently mounted charger/connectors?

I don’t think there’s one overwhelming consistent option, but a few cars include adapters that are 14-50 compatible (I believe some trims of the 2019 Leaf come to mind). If you really want to have a guest charging option, you could buy a 14-50 compatible charging station and just plug it in when guests are present. Clipper Creek advertises this 30A unit as “travel friendly” which implies to me that you can just keep it on a shelf and plug it in when needed. They also have higher amperage units that would probably work but don’t have the “travel friendly” designation. There’s plenty of cheaper, off brand J1772 units also.

 

[davewill]

Great plan. Raises the question: what do the other EV brands use for their mobile connectors? I know a lot of them have 5-15 120V plugs, but how about for 240V? Anybody know? Or do they mostly rely on permanently mounted charger/connectors?

Most of them do not have 240v capable mobile connectors. Some of the newer LEAFs do, but that's pretty much it. If you REALLY want to support all comers, you could install a J1772 EVSE there, and use your J1772 adapter with it for your Tesla. Then anyone could plug into it.