240v plug questions

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The welding outlet in my garage, 3 prong 240v (prongs are vertical) is wired with what I think is 8 gauge to the fuse panel with a 40 amp breaker.

I have a 240v space heater that has a 3 prong plug, but the plugs are horizontal.
Label on the back of the heater says 4800 watts.

What does one need to do to be able to plug this heater in?

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you either need to make a little extension cord that has one end for the space heater and the other end for the wall outlet or change the end on the space heater.
they make several different styles of 240 ends. any decent electric shop should be able to do it for you
the breaker is big enough dont worry
 
you either need to make a little extension cord that has one end for the space heater and the other end for the wall outlet or change the end on the space heater.
they make several different styles of 240 ends. any decent electric shop should be able to do it for you
the breaker is big enough dont worry

your existing plug/socket is a 50 amp 240 volt receptacle. your 4800 watt heater is a 20 amp at 240 volt draw. the #8 wire will carry 50 amps, no problem. as stated, you could either change the socket for one that matches your heater, or change the cord on the heater(cord end) to match the wall socket. (best fix) you'll find the cord end at home depot for about 20-30 bux. cut the end off the heater cord(unplugged) and install new cord end. done. only thing is now you have to unplug the heater to weld. aaaand you won't be able to plug the heater into a standard 20 amp 240 volt socket:meh:. if you hired an electrician or were able to do the work yourself, you could simply add a 20 amp 240 volt socket and circuit to where you want to use your heater...this way, the heater could be used where ever there was the right socket, the welder(other big thingy) could be utilized without turning off the heat...HTH
 
Thanks for the info. I was thinking of making a short extension cord so I could still keep the same plug end on the heater in the rare event I might use it elsewhere.
I was at Home Depot the other night picking up some other crap, and I when I asked their electrical guy about this, just based on the plug differences, he would not sell me anything until he knew amps and wire sizes I had, which is a good thing.
 
Lambcrusher has a good sol'n. The plug you have is a water heater type--dryer types(and welders) always have the vertical pins.
 
I'd get another box, proper socket and some wire to add the proper outlet off of the existing circuit if it was difficult to just run another whole circuit. You would not be able to run the heater and welder at the same time but it would work.
 
I'd get another box, proper socket and some wire to add the proper outlet off of the existing circuit if it was difficult to just run another whole circuit. You would not be able to run the heater and welder at the same time but it would work.

if tapped off of the 50 amp(40 amp) circuit, the wire between the 2 boxes would have to be rated for the same 40 or 50 amps as the overcurrent protection is rated for(per nec...all conductors in a circuit...) this is another possible solution...to run a bit of #8 from the welder plug to the heater plug- BUT, now you have to figure out how to splice the circuit wires together INSIDE of their enclosures- you are not allowed to double tap the terminals of the plug, so that leaves wire nuts(rated for 20 amps only) which then leaves kearnys(very big) or polaris taps(pricey and big) to carry the load of the 40/50 amp circuit thru the splices...


best would be a separate circuit for the heater;


OR
an adapter cord to use heater in welder socket would be next BELOW swapping the cord end on the heater(due to having fewer connections in the circuit.,..)
 
For code, you would have to run the same guage wire, whatever it is. It is not to have enough power which could be covered by a 12 guage.
Price of splices may be high but maybe way cheaper than running wire as it is not just the cost of wire but installation.
Really the proper way is to put a sub panel with the power from the panel going into it. Then 2 circuit breakers, 1 40 for the welder and a 20 for the heater. That way you don't have an oversized fuse for a heating appliance. The 20A C/B would trip and maybe save the garage and maybe house.
If the main panel is in the garage, I don't think the OP would bother asking for help as since there is no drywall, running a circuit is easy for many.
But no drywall brings up the question whether conduit is required or preferred because the wire is exposed.
 
I still haven't done anything on this...but thanks for all the tips. Will most likely do the adaptor cord.

I'm in BC, Canada, eh...we are not required to use conduit. I always thought it odd when going to some US industrial job sites and seeing the massive runs of conduit. We just use cable trays up here for industrial (usually), much easier.
 
For code, you would have to run the same guage wire, whatever it is. It is not to have enough power which could be covered by a 12 guage.
Price of splices may be high but maybe way cheaper than running wire as it is not just the cost of wire but installation.
Really the proper way is to put a sub panel with the power from the panel going into it. Then 2 circuit breakers, 1 40 for the welder and a 20 for the heater. That way you don't have an oversized fuse for a heating appliance. The 20A C/B would trip and maybe save the garage and maybe house.
If the main panel is in the garage, I don't think the OP would bother asking for help as since there is no drywall, running a circuit is easy for many.
But no drywall brings up the question whether conduit is required or preferred because the wire is exposed.

This is the way to go. The #8 is suitable for 40 amps because you have romex (NM Cable). Romex has an insulation temperature of 60 Deg C. so it is limited to a maximum of 40 amps.

The 4800 watt heater is 20 amps at 240 but you should size the conductors and breaker for 125% of the rating, in this case that would be 25 amps and push the wire size up to #10s.

Don't try to cut corners on electrical systems, I have personally seen way too many fires as a result. Just imagine loosing your home to a fire trying to save $20. Your whole life of work gone, memories and important personal items are lost. It is just not worth it.
 
pvc conduit is easy to use. The purpose is that you could drop/lean something up to the wall and damage the wire causing a hot spot. romex is not to be seen.
I do what is safe, which sometimes exceeds codes. And sometimes I exceed code because it is my house and I am worth it.
 

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