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Eric Hartunian
09-09-2007, 5:00 PM
Hi,
I'm wondering if the three-prong outlet for an electric dryer can be fitted with an extension cord to run power to a 220v bandsaw?
Problem is, I move regularly, and usually rent a house. Most property managers will not allow electrical work, like adding a 220v outlet. I figure most homes have a 220v for the dryer, which I think can handle an extension cord into the garage shop.

Any thoughts on this, or am I relegated to 120v machines?

Thanks,
Eric

Bill Arnold
09-09-2007, 5:18 PM
Depending on the distance from the outlet to the bandsaw, there should be no issue other than matching the type of plug. How far will you have to run the extension cable?

Dave MacArthur
09-09-2007, 5:45 PM
Most dryer outlets have 30A service. This should be fine for any bandsaw up to 3HP, and in fact 30A will handle most 5HP applications w/ 220v (unless startup kicks the CB). The extension cord is not really a problem so long as you don't make it the limiting factor in the power supply chain... Get or make a 10ga one. Rough advice, but it should not be even close to any problematic heat levels.

Now, inevitably there are 5 actual electricians that will chime in, and their advice certainly supercedes mine; but keep in mind this is a general answer--yes you can do it, but of course there are various things that would cause problems--bigger motor, smaller ext. cord, foolishly long cord. In the end, the 30A CB is designed to protect the wiring & circuit devices from running too much power, getting hot, and causing a fire. If you use good ga. wires, and it works, the CB will do it's job and you're fine.

Rick Christopherson
09-09-2007, 6:03 PM
Technically it is not proper, but realistically and electrically, it is fine, as long as the dryer outlet is not on a subpanel. If the dryer outlet is on a subpanel, then you run the minor risk of having your bandsaw chassis with a slightly elevated voltage above ground.

The reason is that you are using a neutral wire as a ground wire. On a subpanel, there will be a voltage difference between ground and neutral. Under normal circumstances, ground and neutral are not interchangeable, but if this is a main load center, then the only difference in this rare situation is color coding. This is specific advise for a specific situation, so please don't repeat this without properly understanding the differences in the conductors.

The distance to the tool should not be an issue because the cord will be well oversized for the load you are putting on it.

keith ouellette
09-09-2007, 6:18 PM
In the manuals I have read for my machines it cautioned against the length of cable used to power the motor. It has something to do with the added resistance the longer the cable is. This would put extra strain on the motor and lessen its performance and may shorten its life. The distance the dryer outlet is from the breaker box could be an issue as that will add to the distance your extra heavy extention cord is running to the machine. It is my understanding that this problem can be overcome by a thicker cable to lessen the resitance. You may also want to check the breaker requirements (amp size) for your motor. The breaker is there to protect the motor and if the breaker is to large it will not trip before the motor is damaged.
I have another suggestion about running a set of cables from your main box to an exterior mounted outlet box hung on the wall as apposed to being within it. This is less intrusive than inserting a box in the wall. I have seen it done in a house for a temp. outlet for a large compressor. It was done by an electritian. I would ask one for advice before attempting it.

Eric Hartunian
09-09-2007, 6:20 PM
So basically, this should be no problem, assuming we are not talking about a sub-panel.
Main points seem to be: use a heavy ga wire for the ext. cord, obviously have the right style plug, keep the length manageable.

Thanks again. I don't have the saw yet, but didn't want to buy it and find out that I am out of luck everytime I move.

Eric

Jason Tuinstra
09-09-2007, 6:58 PM
Eric, I had a similar situation and ended up doing this with no problem.

Michael Liechty
08-15-2008, 6:18 PM
Hi,
I'm wondering if the three-prong outlet for an electric dryer can be fitted with an extension cord to run power to a 220v bandsaw?
Problem is, I move regularly, and usually rent a house. Most property managers will not allow electrical work, like adding a 220v outlet.

Thanks,
Eric

I did this exact thing to run a small TIG weldor when I was renting an apartment.

ML

Rollie Meyers
08-16-2008, 2:02 AM
Be aware that a neutral is a current carrying conductor,a equipment grounding conductor is not, it is improper to refer to a 240 volt circuit as "220 volt" and for a ultility to supply 220 V in most states would violate the rules they are regulated under. For the 50 hertz world that does use 220 V the color code is Brown = Hot,Blue = Neutral,and Yellow w/ green stripe = Ground. (It is derived from a 380Y/220V system but the EU has harmonized the voltages to 400/230 since some were 380/220 and others like the UK was 415/240 V.

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