Advice on 220/240V Plugs

ChuckM

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My shop has one 220V power socket for the heater. I am thinking of acquiring one 220V welder, but those have plug designs different from the heater's.

The heater's plug:https://www.rona.ca/en/portable-heater-03915158
The welder's plug:http://www.canadiantire.ca/en/pdp/lincoln-electric-ac-225-stick-welder-0588035p.html#srp

Are there universal adaptors that allow me to use the 220V power supply with different designs of plugs?

This is for electric cars:https://www.amazon.ca/Conntek-30-Amp-Electric-Vehicle-Adapter/dp/B00STD8S7C

Would appreciate any product suggestions or solutions (other than running a second 220V power cord as it is pretty expensive for an electrician hire).
 
The plugs are different because the power requirements for each device are different. the heater has a NEMA 6-30Plug because it probably needs to be on a 30 amp circuit.

The welder needs a 50 amp circuit hence the NEMA 6-50P. So you should probably consider adding a 240-50 amp circuit for the welder.

Ron
 
There are a lot of different plugs out there, but there is a method to the madness.  Take a closer look and there are important details on each one.  Beyond the locking options, they also differ by amperage, voltage, and neutral. In this case, the welder has a 50Amp plug and the heater probably has a 30Amp plug. 

Of course whatever plug you go with, the entire circuit needs to support the expected load:  Not just the plug, but the breaker and everything in between. Although you could put a 50Amp plug on the heater, my concern would be that if there was a problem with the heater, you couldn’t trust the breaker to trip and you could have a fire.  I would either use a separate, properly sized circuit, or consider an inline breaker for the heater plug. 

Well,  in this case, you probably don’t have a choice. Since the other circuit is most likely 30Amp, you’ll need to install a new 50Amp circuit.  Just make sure the panel will support it. 

mwildt said:
I prefer the locking style connectors, like nema L6-20 or 30 etc. use them for jointer and compressor.
https://www.stayonline.com/reference-nema-locking.aspx

It's mind blowing when one looks at all the styles through out the world.
 
Thanks Ron and rjp for pointing out the important differences on the amp requirements. It looks like my more economical option is to go with a 120V welder which I won't be using a lot anyway (as I am more a woodworker than a metal worker, both as a hobbyist). I am glad I received your advice before I went out and got myself a 220V welder -- new or second hand.
 
I don’t know if they make them, but I would look for a 30Amp 240v unit before dropping to 120V. They do have some nice units for 120v 20amp, but for the same type of welder, you cut the capacity in half when going from 240V to 120V. 

I would recommend engaging an electrician, or at least visit welding forums. I see that there may be exceptions for welders as they have lower duty cycles.  I read that the Miller manual shows 14g wire for 30Amp unit, but that may just be the cord, not the circuit.  I’ve never seen anything about electrical codes allowing for diferent duty cycles before, but that doesn’t prove anything. 
 
sgt_rjp said:
In this case, the welder has a 50Amp plug and the heater probably has a 30Amp plug. 

Although you could put a 50Amp plug on the heater, my concern would be that if there was a problem with the heater, you couldn’t trust the breaker to trip and you could have a fire.

Not sure I follow the logic here.  How does the plug affect the breaker to trip?  How does having an over capacity plug affect safety?  The plug just passes the electricity from the lines/outlet to the cord to the motor.  There are no breakers built into the plug itself.  It just moves the electricity along the pathway.  Using a bigger plug than you need is like using a heavier extension cord than you need.  No harm in that.  The breaker back at the box is affected by the voltage drawn at the motor.  Too much voltage drawn and the breaker will trip.  Fine and correct.  Having too heavy a cord or too heavy a plug just means neither will melt when drawing too much voltage.  Good.

Now I go along with everyone else saying to get a separate heavy duty circuit for the welder only and don't mix the heavy duty welder with the light duty heater on a light duty circuit.  Bad.
 
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