Anyway to use a welder plug for 30 amp circuit?

[tom-ky]

Posted this in the heating/as forum but thought I might get better response here.

Looking at the Profusion heaters that have the 30 amp plugs on them. Is there anyway that I could come up with a way to use them off a 50 amp welder plug but still have the 30 amp protection? I guess I am asking if there is a safe way to make a setup that would plug into the welder plug and have 30 amp protection and outlet.

 

[American Locomotive]

You would need a breakout box with a 50A plug on one end, a 30 amp breaker in the middle and a 30 amp outlet at the other end.

 

[tom-ky]

You would need a breakout box with a 50A plug on one end, a 30 amp breaker in the middle and a 30 amp outlet at the other end.

I was wondering if something like that would work. What are you calling a breakout box? I was wondering if a plug with some 10 gauge cord, a box along with an outlet would work.

 

[mrramsey]

Posted this in the heating/as forum but thought I might get better response here.

Looking at the Profusion heaters that have the 30 amp plugs on them. Is there anyway that I could come up with a way to use them off a 50 amp welder plug but still have the 30 amp protection? I guess I am asking if there is a safe way to make a setup that would plug into the welder plug and have 30 amp protection and outlet.

Since the device draws less current than the 50 amp welder outlet there is no issue so long as there is an appropriate plug on the device to match. The breaker protects the wiring not the device.

No differently than pluging 120 volt device that draws only 5 amps into an outlet that has a 20 amp breaker. Smaller can be plugged into larger just NOT Larger into smaller.

Change the cord on the heater to match the welder plug and you have no need for a breakout box...

 

[lakeroadster]

Posted this in the heating/as forum but thought I might get better response here.

Looking at the Profusion heaters that have the 30 amp plugs on them. Is there anyway that I could come up with a way to use them off a 50 amp welder plug but still have the 30 amp protection? I guess I am asking if there is a safe way to make a setup that would plug into the welder plug and have 30 amp protection and outlet.

Are you aware that 50 amp to 30 amp adapters are available commercially?

https://www.google.com/search?q=50+amp+to+30+amp+adapter&ie=utf-8&oe=utf-8

 

[American Locomotive]

Since the device draws less current than the 50 amp welder outlet there is no issue so long as there is an appropriate plug on the device to match. The breaker protects the wiring not the device.

No differently than pluging 120 volt device that draws only 5 amps into an outlet that has a 20 amp breaker. Smaller can be plugged into larger just NOT Larger into smaller.

Change the cord on the heater to match the welder plug and you have no need for a breakout box...

Basically there is concern that the device itself is only rated for a 30A circuit. So it's possible something could go wrong in the device, where it draws say 50 amps without being a dead short. The device's internal wiring/cord may only be rated for 30 amps and could possibly burn.

The safe way to do it would be to have a breakout box that plugs into the 50A outlet, with a dedicated 30A breaker and outlet.

 

[lakeroadster]

Basically there is concern that the device itself is only rated for a 30A circuit. So it's possible something could go wrong in the device, where it draws say 50 amps without being a dead short. The device's internal wiring/cord may only be rated for 30 amps and could possibly burn.

The safe way to do it would be to have a breakout box that plugs into the 50A outlet, with a dedicated 30A breaker and outlet.

And that same case for safety could be made for everything and anything ever plugged into a circuit that has a larger breaker than the devices rating.

Which basically means every device needs it's own breaker box.

Not a realistic approach.

 

[theoldwizard1]

And that same case for safety could be made for everything and anything ever plugged into a circuit that has a larger breaker than the devices rating.

Which basically means every device needs it's own breaker ̶b̶o̶x̶.

Personal pet peeve. Almost all welder, regardless of their size, come with a 50A plug.

You would need a breakout box with a 50A plug on one end, a 30 amp breaker in the middle and a 30 amp outlet at the other end.

Or install a 30A breaker inside the device.

 

[yeldogt]

And that same case for safety could be made for everything and anything ever plugged into a circuit that has a larger breaker than the devices rating.

Which basically means every device needs it's own breaker box.

Not a realistic approach.

You don't understand what he is speaking of .... also, what device comes from a manufacturer with a plug rated higher? That's the point of the plug .. to limit the use.

In the USA we protect using the plug -- in much of the world they use fused plugs or outlets.

Why have breakers and plugs

 

[yeldogt]

Since the device draws less current than the 50 amp welder outlet there is no issue so long as there is an appropriate plug on the device to match. The breaker protects the wiring not the device.

No differently than pluging 120 volt device that draws only 5 amps into an outlet that has a 20 amp breaker. Smaller can be plugged into larger just NOT Larger into smaller.

Change the cord on the heater to match the welder plug and you have no need for a breakout box...

The breaker is the first line of defense -- that 5 amp draw is contained within a device that designed to be plugged into a circuit with a 20amp breaker. The internal wiring will take the load -- or it will have a limiting plug like may devices have.

 

[Falcon67]

Personal pet peeve. Almost all welder, regardless of their size, come with a 50A plug.

Or install a 30A breaker inside the device.

The RV/race trailer uses a "50A" shore cord. It's wired with the "50A option" which is just the larger 240V motor base and a 240V breaker box with no main. The power connection on the side of the shop uses a "50A RV plug" for the hookup. It's a 30A circuit - wire & breaker. Running the AC and lights while docked at the house pulls maybe 20A, if that.

I left enough slack that I could tap into that run for a 240V welder plug, should I ever get around to buying such. I'd be way shocked if a 210MVP pulled 30A. I think they are rated at 24A full output.

 

[mrramsey]

Basically there is concern that the device itself is only rated for a 30A circuit. So it's possible something could go wrong in the device, where it draws say 50 amps without being a dead short. The device's internal wiring/cord may only be rated for 30 amps and could possibly burn.

The safe way to do it would be to have a breakout box that plugs into the 50A outlet, with a dedicated 30A breaker and outlet.

True but most of these devices (especially plug in devices) are thermally protected from overloads. Lots of assumptions here but any plugged in heating device should not be left unattended.

 

[matt_i]

I would just use an old-school 2-pole fuse block mounted in some enclosure, cleaner if it can go in the main heater...but could probably go in a 4" square box @ 2-1/8" deep.
If not find a 6" square NEMA-1 box. Use #6awg input wire to the cord, then connnect thru 30A fuses to protect the insides.

 

[howpeculiar]

The breaker protects the wiring in the building, not anything plugged in. Consider every single 15A cordset you have ever plugged into a 20A circuit. As long as it does not exceed 20A, the breaker does not care what happens to your external device and its cord. The device should have its own protection.

 

[larry_g]

One thing to do here is read the instructions. Some devises will tell you the circuit MINIMUM is 30 amps and others will say use on a circuit NOT EXCEEDING 30 amps. Some devises do rely on the circuit breaker feeding them for protection..

lg
no neat sig line

 

[mm08822]

The first Profusion heater I found by googling was a 5000w 240v unit without a plug. Model# HA24-50M. Instructions state it needs a 30A min circuit and ocp no higher than 50A. Running amps are 20.9a so conductors need to be rated at 125% of that value--> #10's. (This may not be the unit are considering. It is necessary to know the unit of interest to understand installation requirements.)

Since it is a welder circuit, it may not have conductors rated for 50a or even 30a. This needs to be checked. If the conductors are less than #10, you can not hook this unit up to that circuit.

This unit also requires a hard-wired connection which you would need to do to preserve the listed product's proper installation requirements. Again what unit?

 

[tom-ky]

The first Profusion heater I found by googling was a 5000w 240v unit without a plug. Model# HA24-50M. Instructions state it needs a 30A min circuit and ocp no higher than 50A. Running amps are 20.9a so conductors need to be rated at 125% of that value--> #10's. (This may not be the unit are considering. It is necessary to know the unit of interest to understand installation requirements.)

Since it is a welder circuit, it may not have conductors rated for 50a or even 30a. This needs to be checked. If the conductors are less than #10, you can not hook this unit up to that circuit.

This unit also requires a hard-wired connection which you would need to do to preserve the listed product's proper installation requirements. Again what unit?

This is one of them:
https://www.northerntool.com/shop/tools/product_200612632_200612632

 

[mm08822]

This is one of them:
https://www.northerntool.com/shop/tools/product_200612632_200612632

So you still need #10's as a minimum in the welder ckt. The unit is portable and specifically stated as not a fixed unit. All that is stated is plug it into a 30a recept. In order to preserve the units listing, I would do as American Loco stated in his first post. This way you are connecting it to a 30a ckt with 30a ocp. This should eliminate any code issues and device protection concerns.

Preferred method is to run the proper ckt required for this unit.

 

[tom-ky]

So you still need #10's as a minimum in the welder ckt. The unit is portable and specifically stated as not a fixed unit. All that is stated is plug it into a 30a recept. In order to preserve the units listing, I would do as American Loco stated in his first post. This way you are connecting it to a 30a ckt with 30a ocp. This should eliminate any code issues and device protection concerns.

Preferred method is to run the proper ckt required for this unit.

Any suggestions on what box to use?

 

[mm08822]

Any suggestions on what box to use?

Did you verify the existing conductors are #10 or larger? What mfr is your existing panel?

 

[tom-ky]

Did you verify the existing conductors are #10 or larger? What mfr is your existing panel?

Welder plugs are feed from a Square D Homeline box with #6 wire running to the outlets. Each outlet is on a separate circuit. Would like to be able to move the heater to either end of the building I am working on. I may want to get a second one later so I could use 2 at once until I get a better heat source.

 

[mm08822]

Welder plugs are feed from a Square D Homeline box with #6 wire running to the outlets. Each outlet is on a separate circuit. Would like to be able to move the heater to either end of the building I am working on. I may want to get a second one later so I could use 2 at once until I get a better heat source.

Ok wire size is no issue.
Try this:

Also need a 50a plug, 2 Pole, 3 wire, 6-50P
6-3 SO cord
2 Pole 30A cb,
4" sq x 2-1/8" deep box,
30a recept, 2 Pole, 3 wire, 6-30R
4" sq cover.