Home AC Welder Breaker ???

[k0ua]

Well I just pulled the cover off my panel and found the three of you where correct, can't get both legs of 115 from a single c/b slot. **** you all. Since I have no other available slots looks like I will be doing all my welding at my property where I have several unused slots on my 200-amp service. Unfortunately my new plugin is 50-miles from where I sleep. I hope you are all happy!

No you are not done with us that easy.. Just get one of the double 120 volt breakers you were going to get except make it 20 amps instead, for each and replace two of your single 20 amp breakers at the bottom, with the single width double 20 amp breaker move the wire up from the other now vacated slot to your new breaker, now you have 2 slots open and pop in the 50 amp 220 breaker that takes up the two slots and wire it up and you are done, and in the welding business.:thumbsup: Savvy?

James K0UA

 

[Beltzington]

No you are not done with us that easy.. Just get one of the double 120 volt breakers you were going to get except make it 20 amps instead, for each and replace two of your single 20 amp breakers at the bottom, with the single width double 20 amp breaker move the wire up from the other now vacated slot to your new breaker, now you have 2 slots open and pop in the 50 amp 220 breaker that takes up the two slots and wire it up and you are done, and in the welding business.:thumbsup: Savvy?

James K0UA

I thought I didn't have a life, but you made me go out and check and I could add a couple more half height 20-amp breakers to make room. All kidding aside I appreciate the advice, I'll post my first weld for all your constructive feedback.

 

[k0ua]

I thought I didn't have a life, but you made me go out and check and I could add a couple more half height 20-amp breakers to make room. All kidding aside I appreciate the advice, I'll post my first weld for all your constructive feedback.

Allrighty then.. thats the ticket, Just work safe and think through every step, and we will be looking forward to seeing those first welds.:thumbsup:

James K0UA

 

[Danno1]

Unfortunately my new plugin is 50-miles from where I sleep.

No you are not done with us that easy.. Just get one of the double 120 volt breakers you were going to get except make it 20 amps instead, for each and replace two of your single 20 amp breakers at the bottom, with the single width double 20 amp breaker move the wire up from the other now vacated slot to your new breaker, now you have 2 slots open and pop in the 50 amp 220 breaker that takes up the two slots and wire it up and you are done, and in the welding business.:thumbsup: Savvy?

James K0UA

I thought I didn't have a life, but you made me go out and check and I could add a couple more half height 20-amp breakers to make room. All kidding aside I appreciate the advice, I'll post my first weld for all your constructive feedback.

Or, you could make a 50 mile long extension cord. Shouldn't cost too much!!! :laughing:



.

 

[LD1]

The thinking here is that, because a welder is seldom (if ever) designed for 100% duty cycle at its highest rated amperage, you don't need to run heavy enough cable to handle 100% duty cycle at that amperage. For example, if you were going to run a 50-amp electric motor on a given circuit, you would need to use #6 wire because the motor would be expected to be run continuously. But for a 50-amp-draw welder (say, output amperage between 40-140 amps), it may only have 20% duty cycle at any output over, say 100 amps. So there's no expectation that it would ever actually draw 50 amps for any significant length of time. This means that the wire would have time to cool down.

The relevant table of the NEC is 630-11(a). That table gives a derating percentage for each duty cycle percentage. For example (I am just making up these numbers), at a duty cycle of 20%, you might be allowed to derate the max amperage to 60%. So if your welder drew 50 amps max, which would normally require a #6 wire, you would multiply that by 0.6 to get 30 amps, and put in the equivalent wire gauge to handle 30 amps. You would still use a 50 amp breaker, however.

Unfortunately, I cannot for the life of me find a copy of 630-11(a) online, so I can't actually give you the multipliers for the duty-cycle percentages.

Again: this is only for dedicated circuits that only the welder will ever be used on.

Or, you could make a 50 mile long extension cord. Shouldn't cost too much!!! :laughing:



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Not only expensive, but I dont think the current will make it @ 240v:laughing: After about a mile, the voltage is zero.

Gonna have to come up with a transformer and boost that voltage up BIG TIME

 

[BIG DOOLEY]

You could add a sub-panel to make room additional spaces for future expansion.
pull out your dryer breaker and add a 50A or 100A 220vac breaker in it's place and feed it to the sub-panel.
put your dryer breaker and welder breaker in the subpanel and rewire.
you would also have room to add additional circuits later.
I have a sub-panel set-up in my garage.
the house main is the main for the sub-panel or you can shut the breaker off that feeds the sub-panel to work on circuit in the sub-panel.

 

[k0ua]

Not only expensive, but I dont think the current will make it @ 240v:laughing: After about a mile, the voltage is zero.

Gonna have to come up with a transformer and boost that voltage up BIG TIME

Well it sorta depends...Now you are going to say I am crazy and just splitting semantic hairs, and you would be correct. BUT just for the heck of it, lets do some math. Math is good, right? Sooooo lets get started. 50 miles distance of Number 6AWG so the entire circuit is 100 miles and the input voltage is 240 volts the resistance of the #6AWG wire is 0.3951 ohms per 1000 foot. Look it up in Wikepedia. There are 5280 feet in a mile so 100 miles would be 528000 feet so 528 x .3951=208.6128 ohms in the total 100 miles of #6AWG wire! Holy cow! is that all.. now apply 240 volts thru this 208 ohm resistor and it would knock your socks off on the other end if you touched both leads one in each hand, and I am not kidding! how much current could we deliver at the far end 50 miles away (100 miles total circuit) a heck of a lot!:
E=IR so 240 volts = I (the unknown current) x 208 ohms so lets divide thru with 208 on each side of the equation and and you have 240/208 =I and that equals about 1.15 amps of short circuit current delivery:shocked: and if you just took a normal VOM and measured the voltage at 50 miles away.. you would measure 240 volts.. Yep that is right. If it was 1000 miles away you would still measure the 240 volts right up until you start to try to draw some actual current thru this ever increasing resistance then you would have a major voltage drop. But a meter is a very high impedance device and draws an extremely small amount of current to make the measurement. OK you sure are not going to run your welder on this 240 volts at 50 miles thru some number 6 , you are not going to have enough voltage to run hardly anything in the way of an appliance at the end of this, but it would have enough voltage and deliver enough current to easily kill you if your hands were wet and you grabbed it.. to prove the prove the point easily take a 208 ohm resistor and place yourself in series with 240 volts ac and this resistor and you are likely to be dead or at least have the snot knocked out of you. So there you go LD1.. I had a little fun (in my warped twisted mind) at your expense.. yall be safe with electrons out there...ya hear?

James K0UA

 

[joshuabardwell]

I found some 6/2 wire (indoor-rated, but let's not worry about that, shall we?) for $203 for 125 feet, or $1.624 / foot. So that 50 miles of wire will only cost you $428,736. A bargain!

 

[k0ua]

I found some 6/2 wire (indoor-rated, but let's not worry about that, shall we?) for $203 for 125 feet, or $1.624 / foot. So that 50 miles of wire will only cost you $428,736. A bargain!

Hey a bit pricey, but ya gotta do what ya gotta do!

 

[grsthegreat]

But if using a double handled breaker that fits in a single space, 240 volts will not be what's coming out. A breaker of this type can give you two branch circuits, but they will both be on the same leg. This means that the welder will see 0 volts coming in as there will be no difference in potential between the two hot wires coming off the breaker.

What you want to do is put the welder on a two space two pole breaker which will provide the 240 volts you need. If necessary, use a double handled single space breaker to replace two 20 amp branch circuits to make the room in the breaker panel.

And don't worry about the welder creating spikes and whatnot. Lots of people have welders, some like me have several, and I haven't heard about anyone having the issues you are concerned about. My power company provides me with a lot more spikes and sags than my welders do.

absolutely 100% true. you are going to have to use twin breakers (120 volt x 2 spaces) to clear up some additional room in the panel. you HAVE to attach a breaker to both copper buses to reach the magic 240 volts.

also, not all panels will accept twin breakers. as to overloading system, a welder only spikes to 50 amps for a second, then drops dramatically for the duration of the weld. My 50 amp welder actually only draws about 22 amps while welding 1/4" p[late (checked with clamp on meter)