Electrical plug/receptacle confusion

[lgxg]

Hi everyone. I’m hoping I’ve got this about 70% figured out, but wanted to check in with some electrical geniuses here!

I had a new garage built, knew I needed/wanted a 220v and a GFI breaker for a BIAB/single vessel and my harbor freight mig welder. When the electrician installed it in the 100 amp panel (hot tub, car charger, and 220 circuit mentioned above) he put a 30 amp GFI in it. The receptacle that was installed is a dryer outlet (NEMA 14-30).

I bought an anvil foundry on Craigslist and am about to do the 220 conversion using a 20amp 110v receptacle, some wire and a 220v plug. I bought a plug that will work with the 14-30 receptacle. I am following this guide: where he uses this 30 amp 220v plug: Leviton 30/50 Amp 2-Pole/3-Way Grounded Angle Straight Blade Plug, Black-R50-00931-000 - The Home Depot

My welder has a different type of plug that looks like it will go into the dryer outlet and seems to be a NEMA 6-50. It seems it would go into the dryer outlet NEMA 14-30 no problem, but I haven’t yet plugged it in.

From my research on all of these plug types and watching the video about the anvil conversion, I think I have learned that the 14 series plugs have a neutral that neither my welder or foundry will be using. Is this a correct assumption?

1. Can I plug my welder into the 14-30 dryer socket as is? (See picture)
2. Can I use 14-30 plug with my anvil socket? (Essentially ignoring the neutral on the plug, following the wiring as directed in the prior video - where neutral and black are wired both as hots on receptacle). Or should i use something else that doesn’t even plug into the neutral on the dryer socket - something like the plug on my welder?

Thank you!

 

[doug293cz]

If your welder is a 50A unit, you cannot plug it into a 30A circuit. If you want to use 50A welder, you will have to install a 50A circuit for it, or convert the 30A circuit to 50A. Conversion will require the wires to be switched from 10AWG to 6AWG, a 50A GFCI breaker installed, and a 50A receptacle installed ($$$.) And no, your welder plug (6-50) will not fit into the 14-30 receptacle. The blade spacings are different.

Whether you stay with a 30A circuit, or upgrade to a 50A circuit, I recommend putting in a 4 wire receptacle (14-30 or 14-50.) Then change the plugs on your devices to match the outlet. If your device does not require a neutral, then leave the neutral blade on the plug disconnected. You can plug a 20A or 30A device into a 50A outlet.

Brew on

 

[lgxg]

Thank you Doug!

The electrician is coming tomorrow to talk about car chargers and hot tub circuit. This is a 100 amp panel on 300 amp total service (all electric house). Hot tub is to be 50 amps, Same with car charger. All three wouldn’t be used at same time - car charger @50, welder/brewery @30?, and hot tub @50 amps.

Is this a correct principal - that the device needs to pull less than the wire/breaker is rated for AND the receptacle and plug should be matched.

WELDER:

This is the manual for the welder: https://manuals.harborfreight.com/manuals/68000-68999/68885.pdf
Page 7 says it pulls 20amps at 240V.

But I’m definitely hearing not to use the current 6-50 plug in a 14-30 receptacle. I’m boggled why the welder would have a 6-50 plug when it only pulls 20 amps. Maybe welders are more commonly plugged into these 50 amp circuits? Maybe my welder is just a small one.

I only do hobby welding - art projects, small brewing projects, etc.

BREWERY:

The Anvil foundry has 2800 watts at 220v pulling ~13 amps At 100%. I am going to create an adapter to go from the current 120V plug with a 20 amp receptacle to the 14-30 plug to follow the principal of matching the receptacle that I have now. I am going to follow the video referenced above.

Thank you for the help!

 

[doug293cz]

Thank you Doug!

The electrician is coming tomorrow to talk about car chargers and hot tub circuit. This is a 100 amp panel on 300 amp total service (all electric house). Hot tub is to be 50 amps, Same with car charger. All three wouldn’t be used at same time - car charger @50, welder/brewery @30?, and hot tub @50 amps.

Is this a correct principal - that the device needs to pull less than the wire/breaker is rated for AND the receptacle and plug should be matched.

...

Yes the device needs to pull less current than the circuit (wire + breaker) is rated. Receptacles and plugs must match. NEMA has worked very hard to make it almost impossible to put the wrong plug in a receptacle - they just won't match up.

Tell your electrician about everything you want to do, and then take their advice.

Brew on

 

[Orangecrusher]

It sounds like you're someone who can afford to do things the right way. I would just have separate receptacles installed for each load. Having said that I have always had welders/plasma cutters/powder coating ovens/ect. and I am an electrician apprentice (work with electricity all day) and in my own home I've never needed anything more than a 30 amp service(receptacle) for my rigs and I've had some big dinosaurs. It's possible they have suggested a 50 amp because of a high in-rush current. Regardless, your electrician ought to be able figure out what you'll be pulling max at any one time and factor in room for error. Most things electrical are designed with a certain amount of headroom to allow for weird unexpected loads. It never hurts to go too big with wire or small with breakers(to start). It can be harder to terminate and more expensive. Personally, I can't stand dryer plugs and receptacles. They aren't designed to be unplugged and I believe using them in a way that requires plugging and unplugging dangerous. In my equipment, I only use twist-lock type plugs and receptacles especially for 240V circuits like the ones made by Hubble. They are great to use with SJO cords, tend to be water resistant/durable and lock together nicely. I have used three phase plugs just to get the current capacity I wanted even though they usually have an extra terminal I don't need. They cost about $20ea. but when I grab that big plug in my hand I feel confident it won't fail on me when I go to plug it in. If you go 50A just use the same style plug on all your devices regardless of wire size(at 50A it will probably hold whatever you got)and plug them into one receptacle. Just make sure you have tight terminations and solid grounds.

https://hubbellcdn.com/prodimage515/WBP_HBL2661_PRODIMAGE_515.jpg

 

[bp100a]

I opted for a 220/20a GFCI breaker in my breaker box and a dedicated NEMA 6-20 plug. For Anvil all I needed was an “adapter”, I used the ‘Tekit Black NEMA 6-15P Universal Plug Adapter 110-250V’ I found on Amazon. I wanted to keep the plug end compatible with the expected current load of the system.

 

[RufusBrewer]

I have to wonder: Will they let you put multiple sockets on a single 50 amp breaker and you have to know that you can only use one at a time?

Example: If you have a 2 ea 50 amp sockets and 1 ea 30 amp socket, you install 2 ea 50 amp breakers and 1 ea 30 amp breaker in your panel.

Maybe this is not required, but I suggest you are prepared to respond if this turns out to be the case.

 

[bp100a]

Isnt that how all houses are wired, multiple receptacles on a single circuit? The breaker will protect the wiring, it’s on the user to not trip it incidentally.

 

[RufusBrewer]

Yes, they daisy chain 115 VAC sockets and lamps on a single 15 or 20 amp breaker. The assumption is you will be using a combination of several "low power" devices not very likely to to exceed the ~1,800 watts total. Which seems reasonable to me.

If you are putting in a 240 VAC 50 amp circuit it is because you need somewhere around 10,000 watts. That is a hefty power draw.

As I said, maybe you can daisy chain 240 VAC 30 and 50 amp circuits. I do not know one way or the other. If I had to place a bet, my money would be 1 socket per breaker. Hence my advice is to to assume you can daisy chain receptacles.

 

[itsnotrequired]

the nec doesn't explicitly prohibit multiple receptacles on 50 amp circuits but limits their use to fastened-in-place cooking equipment. there is more flexibility in non-dwelling units but then there starts to be definition games with detached structures. the real kicker is the irc (international residential code), this does not allow multi-receptacle circuits on anything over 20 amps. almost every state has adopted the irc (except for wisconsin, lol).

 

[Nate R]

Wait... you can have hot tub OR anvil plugged in???
I would make sure the hot tub is always on, and on it's own circuit...
I would want a quick soak after a brew day!!