50 amp shore power adapted to NEMA 6-50R ?

[K-2]

How do I do this? We have NEMA SS2-50R on the floats. I think that is correct? It's 230 volt 50 amp .
I want to power my Millermatic 190 welder, the plug on that is NEMA 6-50P .
I DO NOT own a 230v50a shore power cord, I have no use for one (until now)
I want the cord to be 25' long. Can I just buy the "ends" I need and a length of wire and build the power cord?
If I bought a 230V shore power cord,,,I can't find an adapter to plug in the welder, so I would have to cut the end off and put on a NEMA 6-50R, that seems like a big waste of $$ . What's the best way to go about this.Thanks

 

[MTboatguy]

A 25 foot long 50 amp cord is going to be expensive, no matter which way you go. Do you have a place that scraps RV's in your area? If so, you might be able to get them to sell you a cord off a wrecked RV, most of the larger RV's these days have 50 amp service. If you can find one, then you can put what ever ends you need on it.

 

[bruceb58]

If it's something your just going to do a few times, just buy some Romex of the appropriate gauge and put ends on that.

 

[bigdee]

If it's something your just going to do a few times, just buy some Romex of the appropriate gauge and put ends on that.

Agree. Also you only need 10 gauge wire for that welder.

 

[NewfieDan]

Agree. Also you only need 10 gauge wire for that welder.

How do you figure that? I don't think Miller is in the habit of putting on bigger plugs than needed. If it came with a 50A cord, why would you risk feeding it with a wire rated for 30A?

 

[hungupthespikes]

Input. 240V, 21.7 Amps, 60 Hz

per:
http://www.millerwelds.com/products/mig/product.php?model=M00487

Lamps, power tools. lots of things have a bigger amperage plug than the wire, no biggie.

The 190 is not what I'd call an inexpensive welder, so Miller upgrades the plug?

Here's a how to:
http://weldingweb.com/showthread.php?11537-HOW-TO-make-a-220V-extension-cord

Buying a welder extension cord and changing the plug would be my choice, more money, but the welder cord would be more resistant, etc..
It's just made for the job.

huts

 

[bigdee]

How do you figure that? I don't think Miller is in the habit of putting on bigger plugs than needed. If it came with a 50A cord, why would you risk feeding it with a wire rated for 30A?

The full load current of that welder is only 21.6 amps. Actually for temporary use you could get away with 12 guage by using shorter (20%) duty cycles

 

[MTboatguy]

I called one of our local RV wrecking yards this morning, looking for something for my 5th wheel and asked them if they had an 50 amp RV power cords and what it would cost to buy one, they told me, yup $15 bucks each, they had 3 that were 35 footers down there right now.

In reading Bigdee's post, if it is only drawing 21.6 amps, you could get away with a 30 amp RV cord and they had 25 footers at the wrecking yard for $10 bucks each.

 

[K-2]

The fly in the ointment is that the 50 amp RV plug and 50 amp 125/250 volt marine plug are different.
The marine plug , NEMA SS2-50P is not a cheap item: $63 is the cheapest I have found, and that's just the plug, I still need wire. The other end, that the welder would plug into is cheap, $15 bucks all day long-Lowe's, Home Depot.
I am glad to hear I can use smaller wire.
Here is my first choice so far: I found a 25' marine shore power cord, 50A, 240volt for $99, it has the correct male plug I need, looks like your basic yellow shore power cord but BIGGER, the wire is 6/3 . More money than I wanted to spend but it will last and it makes it simple, just cut off the female end and install
a receptacle that the welder will plug right into. That's not my final decision, still researching. Thank You to everyone who has helped.

 

[NewfieDan]

The full load current of that welder is only 21.6 amps. Actually for temporary use you could get away with 12 guage by using shorter (20%) duty cycles

I know I am in Canada, which is different than the US, but our Electrical Code is based closely on the NEC. So I will reference our code knowing that it is in many ways similar to the US. I won't go into detail but Section 28 of the electrical code does not allow what you are saying. With 26yrs as an electrician I have a little experience in this.

 

[bigdee]

I know I am in Canada, which is different than the US, but our Electrical Code is based closely on the NEC. So I will reference our code knowing that it is in many ways similar to the US. I won't go into detail but Section 28 of the electrical code does not allow what you are saying. With 26yrs as an electrician I have a little experience in this.

It is all about DUTY CYCLE. Read NEC article 630 and look at table 630.11. Conductor size formula is 21.6 x .69 = 14.9 amps. In other words conductors for this welder can be de-rated to 15 amps. Breaker size cannot exceed 200% of full load amps which is 40 amps in this case. Yes, 12 guage wire on a 40 amp breaker is what code allows.

 

[K-2]

GOOD We got some sparkies on board !
If the 50A shore power cord is 4 wire and the welder is 3 wire, how do I do this?

 

[bruceb58]

You don't need the neutral.

 

[K-2]

OK I have another option that leads to another question.
Can I run this welder off a generator? Is this a good idea? Possibly harmful to welder?
What size generator would I need? Thanks!

http://www.millerwelds.com/products/mig/product.php?model=M00487

 

[MTboatguy]

OK I have another option that leads to another question.
Can I run this welder off a generator? Is this a good idea? Possibly harmful to welder?
What size generator would I need? Thanks!

http://www.millerwelds.com/products/...p?model=M00487

Big enough generator you can run anything, but the cost to pick one up is going to be a heck of a lot more expensive than coming up with a shore power cord, even if you do have to pay $65 bucks for the correct ends! You would need a generator in the 7000-10000 watt range that is rated to put out up to 240 V and 50 amps.

 

[K-2]

I forgot to mention it is my friends gen set.
Plan A is to get the shore power cord and the Home Depot $15 end.
Plan B is to use the gen set if I am away from handy shore power plug in.
Now I have plans to deviate from

 

[MTboatguy]

Take into account, you will probably have to build an adapter to run your welder off a generator, many of them, even in that power range have twist lock 50 amp plugs designed for RV use.

 

[K-2]

For some reason I am spooked about running that welder off a generator. Fear of damaging the welder .
I have no specific reason, it's just stuck in my head.

 

[MTboatguy]

Welders are run off generators all of the country, everyday of the year, as long as you are not overloading the generator causing big fluctuation in the current, there should be no problems at all.

 

[NYBo]

Welders are run off generators all of the country, everyday of the year, as long as you are not overloading the generator causing big fluctuation in the current, there should be no problems at all.

Isn't that what the guys with mobile welding services do?