240v Extension cord

[pault28]

I’d like to add 240v capabilities in my garage for a 3hp saws top table saw, and also my miller diversion 165 tig welder. This space is temporary so I don’t want to run cable underground or do a subpanel. I’d like to hook up a 240v 6-50 receptacle on the side of the house. I believe a 30A breaker and 10g wire will be sufficient to the receptacle from the main panel. I’d like to run an extension cord into this to pull out to the detached garage when needed. Is it ok to use a 100’ 10/3 cord (terminated with 6-50 plug and receptacle) plugged into this receptacle? I don’t need 100’…I need about 60’, but I have a 100’ 10awg cord. I can cut and reterminate it if need be to eliminate the extra length. The cord will never sit outside except literally when being used. The saw pulls 13A and the welder pulls a max of 25A. I’m hoping oversizing the extension cord to 10g will be sufficient and safe. Thoughts?

 

[wyliesdiesels]

why would you install a 50a receptacle for a 30a circuit?

 

[pault28]

why would you install a 50a receptacle for a 30a circuit?

Because the plug on the welder is a 6-50 from the factory.

 

[dcg9381]

Because the plug on the welder is a 6-50 from the factory.

I have a 14-50 ends on a 50' 10/2 SOOJ extension cord that I use for my welder. I do it that way because we've got several 14-50R around the property. I'm aware that it would be better for all of these to be 30A circuits. If someone tried to improperly use that extension for an RV, it doesn't have a neutral and wouldn't function. It's got "welder only " labels on it

why would you install a 50a receptacle for a 30a circuit?

I've got this setup too the 14-50R have a sticker that says 30A. I use it for RVs. The reality is 240V @ 30A will power pretty much any "50A RV" until you get into 3+ AC rigs - which are not things common to my property and would blow the breaker anyway.

 

[mm08822]

I have a 14-50 ends on a 50' 10/2 SOOJ extension cord that I use for my welder. I do it that way because we've got several 14-50R around the property. I'm aware that it would be better for all of these to be 30A circuits. If someone tried to improperly use that extension for an RV, it doesn't have a neutral and wouldn't function. It's got "welder only " labels on it


I've got this setup too the 14-50R have a sticker that says 30A. I use it for RVs. The reality is 240V @ 30A will power pretty much any "50A RV" until you get into 3+ AC rigs - which are not things common to my property and would blow the breaker anyway.

Be careful, if an L14-50 is used without a neutral, such as to feed an rv panel, any 120v loads on opposite legs that are turned on will be effectively placed in series with 240vac. Some of these items stand a great chance to burn up.

If the 120v loads were all on the same leg, nothing will operate and no damage occurs.

A single 120v load will not operate and no damage occurs.

Unless, you are there, "welder only" labels could easily be ignored b/c people don't understand the issue.

 

[dcg9381]

Be careful, if an L14-50 is used without a neutral, such as to feed an rv panel, any 120v loads on opposite legs that are turned on will be effectively placed in series with 240vac. Some of these items stand a great chance to burn up.

I don't feed panels with extension cords, so I'm not sure what you mean. I think you mean use that cord to feed an RV (which has a panel). All of the RVs I've owned and worked on are 120V only and have no 240V applications. I'm not understanding how I'm risking energizing an RV with 240V because of a missing neutral wire. I'm not actually familiar enough with RV AC panels to know how they split the legs, but I assume they do.

Trust me, RV parks do not have the most reliable electrical systems. I've seen broken neutrals and broken grounds more than once at the 50A posts.

 

[mm08822]

Yes, feeding an rv panel ultimately as was the situation you mentioned.
If your rv only uses 120v supply then worst case nothing works w/o a neutral present.
For the rv 's that use 120/240vac, 3p, 4w, your cord could create the issues I mentioned.
For the unsuspecting, there is the expectation that the installed plug/recept configuration implies everything is wired properly.

 

[wyliesdiesels]

Because the plug on the welder is a 6-50 from the factory.

So youre gonna use an adapter on the table saw?

 

[dcg9381]

If your rv only uses 120v supply then worst case nothing works w/o a neutral present.

I've owned "50A" RVs with 2 ACs - they use both legs of the circuit, but there is nothing 240V on these units. I've never really investigated how the legs are brought into the RV panel or how the legs are split... I've never seen an RV that uses 240V anything - not even in the big 5th wheel space. Maybe when you get into tour busses or really high end stuff?

 

[PCustoms]

Stick a small sub panel in the shop. Put an inlet/pigtail on it for the 6-50 cord.

Cord crosses yard when needed, other then that you can use standard wiring where needed.

 

[pault28]

So youre gonna use an adapter on the table saw?

I will have to use an adapter on one of the two tools. That’s why I figured the 10awg cord would be overkill, but safe, as it is good for 30a, which neither of the two tools draw, and I will lose a little bit to resistance with a longer cord. I actually do not own the sawstop table saw yet. I’m not sure what connector it has on it, or if it unterminated from the factory.