50A receptacle & Need a Heater

[Petvan]

Hi All,

The last owner of my home has what appears to be a 50A receptacle I expect for an arc welder in the garage. I figured out it's wired to a 2 pole 20A GFCI on the panel (I _think_ these can support 50A when ganged)

I am going to check the wire gauges for safety.

I don't weld, but would like a heater, possibly one that I could remove in the summer (pluggable makes sense).

The plug is the one below and I don't see much in the way of heaters using it.

https://www.amazon.ca/dp/B000GAX88U/?tag=atomicindus04-20

Looking at some threads here and basic knowledge tells me my options are to make an adaptor cable and keep the current plug and ideally rightsize the breaker to my heater, or change the plug & breaker combo to something more typical of 3000-4000W heaters (20/240).

Just curious if I'm missing any options before I start shaking it up? Neighbor tells me Tesla use the same plug for charging and maybe I like that idea in future ;-)

P

 

[Denwood]

Keep the plug for your EV to come...

 

[rjacobs]

that is a welder only plug... it has no neutral.

I dont think you will find any heaters or tesla chargers that use a 6-50R...

If you want to fix it, fix it correctly with the proper outlet, proper gauge wire for your load, and proper breaker.

Welder 50a circuit can get away with smaller wire because its a duty cycle limited device as well as generally used in short bursts. I think I was running 10g on my 50a welder plug(like 3 foot run from the breaker) when a full 50a device would require at least 8g if not 6(depending on the run length).

 

[Don1357]

There is a common misconception around "Oh, it has a breaker so big that I better change it down to closer to what I'm going to use". That's not how electricity works. You may often plug an USB charger drawing 1 amp of power to a 15 amp outlet, 1,500% more, and never worry about it. That's because as far as the cabling is concerned the only worry is an appliance attempting to draw more power than the wire is capable of handling in the form of heat buildup. That's why there is a breaker, to protect the wiring (and the house from burning down) not the end device.

I'll be corrected in a hot second if I'm wrong but I think you can change the plug to a rating smaller than your breaker, but you can't change it to something capable of handling bigger than your breaker. That's because you don't want even the remote possibility of something that draws more power than the cable is rated for. If the house burns down because of that your insurance may even bail on paying for it.

 

[Showkey]

that is a welder only plug... It has no neutral.

I dont think you will find any heaters or tesla chargers that use a 6-50r...

If you want to fix it, fix it correctly with the proper outlet, proper gauge wire for your load, and proper breaker.

Welder 50a circuit can get away with smaller wire because its a duty cycle limited device as well as generally used in short bursts. I think i was running 10g on my 50a welder plug(like 3 foot run from the breaker) when a full 50a device would require at least 8g if not 6(depending on the run length).

Tesla support:

 

[EricS]

A 2 pole 20A breaker supplies 20A and should have a 6-20R receptacle. If you were to plug in a Tesla it would trip the breaker.

If the wire is rated to current breaker, it's possible to still use for a heater ( voltage/current rated for wire/breaker) just replace the receptacle for the correct one( plug in) or hard wire heater into existing receptacle box

 

[nadogail]

My 5 KW shop heater is connected to my 50 Amp Welder circuit with 10 Gauge Wire, a 30 Amp fused disconnect and a less than 10’ tap connection.

 

[Stuart in MN]

I figured out it's wired to a 2 pole 20A GFCI on the panel (I _think_ these can support 50A when ganged)

A two pole 20 amp breaker is good for 20 amps at 240vac, you don't double the value because it's two pole. Assuming the previous owner was using it for a welder, there are provisions in the electrical code for running a welder on a breaker that would otherwise seem too small since they are a very intermittent load. On the other hand, an electric heater is a continuous load, so whatever heater you use will have to be sized for 240vac 20 amps. That will probably limit you to a 3,000 watt (3kw) heater.

You also need to confirm what size wire is installed - since it's a 20 amp breaker the wire is probably 12 gauge, but you need to check.

 

[jayoldschool]

Swap it out for a 6-20 and you're good. I charged my Volt and ELR from a 6-50 and a 6-20.

 

[theoldwizard1]

that is a welder only plug... it has no neutral.

So what ! It is 240V ONLY.

The real issue is, what size is the breaker and wire leading to that outlet.

 

[RoadBeater]

I’ve got my 7.5KW plugged into my welder outlet, no problem with it.

 

[Stuart in MN]

I’ve got my 7.5KW plugged into my welder outlet, no problem with it.

That may be, but you also must have a larger breaker and wiring than the original poster - his 20 amp breaker won't work for a 7.5kw heater.

 

[Petvan]

Great info all and thanks! I will confirm the wire gauge for sure. Point on 2-pole 20A getting me 20A @ 240 is well taken also. I will go the the road of new plug and aim for a 20A heater and forgo the Tesla plan for now ;-). Neighbor with one saw my outlet and suggested it was the right one in passing but obviously casual.

Cheers!

Pete

 

[Hobby_Man22]

There is a common misconception around "Oh, it has a breaker so big that I better change it down to closer to what I'm going to use". That's not how electricity works. You may often plug an USB charger drawing 1 amp of power to a 15 amp outlet, 1,500% more, and never worry about it. That's because as far as the cabling is concerned the only worry is an appliance attempting to draw more power than the wire is capable of handling in the form of heat buildup. That's why there is a breaker, to protect the wiring (and the house from burning down) not the end device.

I'll be corrected in a hot second if I'm wrong but I think you can change the plug to a rating smaller than your breaker, but you can't change it to something capable of handling bigger than your breaker. That's because you don't want even the remote possibility of something that draws more power than the cable is rated for. If the house burns down because of that your insurance may even bail on paying for it.

Yeah the wire is sized to the breaker. They are concerned about the wiring in the wall catching fire. As far as plugging in something that draw 6 amps when the circuit is sized for 15 or 20 well i'm not sure what their thinking is. I guess that's a bit more obvious if the device your using catches fire.