Running 220v from 110?

AlanB said:
The dryer outlet is 240V (as was mentioned). There are available switch boxes that allow switching between the dryer and an electric car charger. Only one can operate at a time, but it avoids unplugging the dryer, and it avoids hacking the house wiring. The box has an input cord and two outlet jacks, and a control to select which has power.

Another possibility is to put a 3 phase motor on the lathe and use a 120V to 240V VFD. Since this would be limited to 15 amps it could theoretically develop 2.4 horsepower but generally the available VFDs are limited to 1.0 or 1.5 horsepower at 120V.

Or put a 120v motor on the lathe. Downsize the motor but keep the same RPM. This will reduce cutting performance but may be adequate for most things.
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I have a three phase motor and run it with a vfd. Does that change anything?
 
Does you VFD convert 1PH to 3 PH?
 
I have a standard 30 amp 220v circuit that the vfd connects to. It's Mark Jacobs setup with the Hitachi vfd and Mark's upgraded control board.
 
Most guys I know who have to occasionally run a big welder just unplug their electric dryer and plug the welder into that. It’s all doable. Tap the dryer or find two outlets on separate phases. Or just get an electrician to run a new circuit.

Better yet....buy a book....and run the circuit yourself. It ain’t rocket science. You can even run it through conduit if you don’t want to rip any Sheetrock

wiring how to book
FWIW.... these Black and Decker books on wiring are about as easy to understand as one can get. With pages of great diagrams showing the way the circuit looks like. And a used one with codes of 2017 is good enough in my opinion
 
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Some VFDs are designed to run from 120V and produce 240V three phase. The amount of 120V available in your rental is an issue. If you have 20 amp circuits they can provide 2.4 kW maximum, and the required 20% derating for continuous loads would reduce that to 1.9 kW. 15A circuits would be correspondingly less. A continuous load is defined as over 3 hours continuously, so your usage may not require the derating. This is for the NEC in the US, it may be different for other parts of the world. So the question is if you can find a VFD rated to operate on 120V and deliver power to your existing motor while staying within the ratings of your circuits. 3 HP is 2.2 kW. Get the specs from your motor and your power outlets and have a conversation with a VFD supplier to see if they have a product that will meet your needs. It may not be able to generate the full 3hp at 120V, but that might be a tradeoff you would be willing to consider. I have seen 120 to 240 VFDs rated in the 1.5 hp range but I have not tested them.

The 240V dryer outlet should be able to feed your existing VFD and Motor. That would be a much simpler solution. If you change VFDs you will probably have to deal with programming and wiring changes.
 
Tim9 said:
Most guys I know who have to occasionally run a big welder just unplug their electric dryer and plug the welder into that. It’s all doable. Tap the dryer or find two outlets on separate phases. Or just get an electrician to run a new circuit.

Better yet....buy a book....and run the circuit yourself. It ain’t rocket science. You can even run it through conduit if you don’t want to rip any Sheetrock

wiring how to book
FWIW.... these Black and Decker books on wiring are about as easy to understand as one can get. With pages of great diagrams showing the way the circuit looks like. And a used one with codes of 2017 is good enough in my opinion
Click to expand...

I have no issue running my own circuit, but I am not going to do that on a temporary rental house. The dryer plug might be an option.
 
I assume you be renting a house not an apt? If that is the case, then you most likely will have a 220V single phase circuit for the dryer and range. You may only need to fab up an extension cord to get it from the dryer connection to the garage. You may even have a dryer outlet in the garage that you can plug into.
 
I looked up the electrical specs on your lathe. It takes 220v, 3phase, at 20 amps. I assume that you have a VFD that runs on 220v. So you could run it off your dryer circuit. How far away will be the lathe which means that you must run an extension chord. I'd have to look up the formula, but you better make sure that the wire gauge is heavy enough. The simple solution is to find a house that has maybe a garage that already has a 220v outlet to rent.
 
Papa Charlie said:
I assume you be renting a house not an apt? If that is the case, then you most likely will have a 220V single phase circuit for the dryer and range. You may only need to fab up an extension cord to get it from the dryer connection to the garage. You may even have a dryer outlet in the garage that you can plug into.
Click to expand...

It will be a house and I hope it doesn't have the dryer in the garage. I guess I could get some heavy gauge wire and build an extension cord.
 
That would be the simplest, although you would have to leave the door open between the garage and house to get it through. Our last home had the outlet for the dryer in the laundry room and another in the garage. Maybe you will luck out. In either case, if you had your VFD hardwired in, you will need to fabricate some type of extension cord. But at least it is only 3 wire as you shouldn't need the Neutral.
 
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