Advantages of Higher Voltage

Switching to 240 volt equipment can boost performance and cut costs. October 30, 2005

Question
Is there any real gain to be made by switching a table saw from 110 volt to 220 volt?

Forum Responses
(WOODnetWORK Forum)
From Gene Wengert, Sawing and Drying forum technical advisor:
You should think about using a 240 volt motor, as it will work on 220 and 230, but the reverse is not true. I suggest that 120 v motors are easier to replace and typically have less heat. There is a very slight power saving advantage in a 240 motor. The 240 will also work better when you are a long distance from the power supply and have line losses, compared to 120.

The real benefit in changing motors is if you can change to 3-phase. There is no question about it - 3-phase motors are better than identical horsepower single phase motors. 3-phase motors are smaller, less expensive, have higher starting torque, are more efficient, use less current per phase, do not require a starting capacitor, and are easier to repair.

But here is the main concern - do you have 3-phase available? If available, then everything is positive for 3-phase motors, with no negative concerns. However, if 3-phase is not available on the lines outside your plant, it will often be extremely expensive to have the electric company bring 3-phase to your facility. It can be so expensive that it will be 10 years or longer before you can recover the costs through the savings of 3-phase motors. It is not easy to make 3-phase yourself from single phase line, although converters are available.



From contributor A:
The main benefit is the smaller wire size it takes to feed the motor. You will be drawing 1/2 the amps on a 220v motor than with a 110v motor. Let's say your motor pulls 30 amps at 110v. You would need to run wire from your panel on a 40 amp breaker and the wire size would need to be at least #8 copper. Now letís take that same motor running on 220v. 30 amps is cut in half to 15 amps. A 20 amp breaker can feed it with #12 copper wire. You will get big savings, it is easy to pull, and there are lots of advantages. The two pole 20 amp breaker will often be cheaper than a single pole 40 amp breaker. Price it out in both configurations and make your decision.


From contributor B:

Yes, switching your saw to 220/230/240 is better for your shop. Currently you are running the saw on one leg of 110 and at apparently 15 amps, depending on your saw. When you switch to 220 your saw will be running on two legs of 110 and at 1/2 the amps divided on two legs. Fewer amperes equals less cost. As to the 3-phase issue, yes it is great to have if you have a large shop with many big machines but, for the one man shop not a necessity. A phase converter is cheap on ebay and can give you 3-phase very easily.