220 vs 110

Electrical costs being the same across the board I know that running my Mig and my Big welder on 220 is cheaper because it is actually more efficient and uses less than 1/2 of the watts that it uses on 115 VAC. However these machines are also Power Factor Corrected with a bank of huge capacitors inside the units to help smooth the demand and surges that welders cause, so that may account for the small savings I get running the 220. Small electric motors that run on 220 do make less waste heat and heat is watts so if they make less heat they are using less energy. Kind of an oversimplification but that is essentially correct for most applications. Hope that helps.

Bob
 
Woops totaly wrong on the decresed power bill running 220. KWH kills that idea.
Did find this tidbit.
The power dissipation in the wires will be reduced by a factor of four when switching from 110V to 220V if the gauge remains constant. If the tolerable amount of power dissipation (heat generation) per lineal foot is constant, doubling the current will require doubling the wire diameter (quadrupling cross-sectional area). Being willing to deal with 220V cuts by a factor of four the amount of copper required for the wires feeding something like a stove. That's a major cost savings

Heat generation in wires and motors causing incresed resistance is the only other cost increasing on 110v and that is unlikely on a small lathe.
 
To elaborate on what Ray said. Say you have a 110 circuit, and a 220 circuit, both pulling 1010W (hey, the math works out easy...). Lets say that the they are both wired with 12GA copper wire. At 110V you will need 10A; at 220V, you will need 5A. Nope, not quite.

See, you won't get exactly 1010W out the other end because you are going to lose some power in the wire. It won't be much, but it will be based on the amount of current you are running through the copper, not the amount of power you are drawing. Put it another way, you are going to lose twice as much power when running 10A at 110V, than you would running 5A at 220V. This is probably not going to be more than a couple watts max, so don't loose sleep over it.

If it were me, and I had 220V, and the equipment was capable of it, I would definitely go 220. The main reason for me is that it helps to balance the electrical panel (putting lots of large loads on a 110 circuit can be a crapshoot)
 
My 2 cents,

to oversimplify, it's kinda like having a Diesel in a Big Rig VS equipping the Rig with a gasoline engine of the same displacement.
both engines when geared correctly can transmit large amounts of power to the ground.
The reason Diesel engines are used comes down to efficiency, it an internal combustion engines' case it's Volumetric Efficiency.
there is more energy per gallon available to a diesel engine than there is available to a gasoline engine of equal displacement.

I would say that running a piece of equipment on the highest voltage available is the most efficient. Power Companies transmit over 50,000 volts because it's more efficient and then transform it down to 460/240/120 for us to use.
why do you think there are 460/480 volt systems , because it can do more work(higher potential difference) with less current
creating the sought after efficiency.
Would you rewire your house for 24 volts for efficiency and then try to fire up a 10 hp RPC on 24 volts (or 12 volts or 6 volts)???
not unless you have a couple hundred(thousand) amps to spare!!!!
But, you could fire off that 10hp RPC on 240 volts easily and even easier on 460 volts due to the higher potential difference between phases that essentially is proportionate to the amount of work that can be completed in a given time(horsepower)

in hobby equipment the effect is very minor, most times motors less than 2 hp are utilized and the currents are relatively low,
but once you start getting out of the 15 hp range you start getting into the 460 volt zone where it is more efficient to go with larger voltages to bring the currents down .


If i were in your shoes i'd run everything i could on 220 or 221, whatever it takes!!:lmao:
Good luck
mike:))
 
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I run into this a lot on woodworking related machinery as well:

110 vs 220:

220 will make your motor happier due to shorter start up time and recovery time - so it might "feel" like it's faster and more powerful, but at the end of the day - you are not saving on energy/electricity as it is the same ( 10amp x 110v = 5amp x 220v), and the motor will not give you more power (a 1HP motor is a 1HP motor regardless of what Voltage is it running off of).

so the benefits are quite simple - shorter recovery/start time on motor, and separation from anything else running off of same 110v line (lights, fans, etc) which might show a drop in voltage if your motor is under extreme load (dim lights etc). not usually an issue, but these are the benefits. no more , no less.
 
PurpLev said:
I run into this a lot on woodworking related machinery as well:

110 vs 220:

220 will make your motor happier due to shorter start up time and recovery time - so it might "feel" like it's faster and more powerful, but at the end of the day - you are not saving on energy/electricity as it is the same ( 10amp x 110v = 5amp x 220v), and the motor will not give you more power (a 1HP motor is a 1HP motor regardless of what Voltage is it running off of).

so the benefits are quite simple - shorter recovery/start time on motor, and separation from anything else running off of same 110v line (lights, fans, etc) which might show a drop in voltage if your motor is under extreme load (dim lights etc). not usually an issue, but these are the benefits. no more , no less.
Click to expand...

Then why did I have to lessen the load on my air compressor when I rewired the motor from 220 to 110?

Bill
 
Without seeing the motor nameplate, or knowing more about your particular motor, I would guess the motor is not rated for continuous duty at 110v. If it is a large motor, you may not be able to pull enough from a normal 110v circuit to run the motor at full power. The max you can hope for from a 110 circuit is 15 or 20 amps, that's 1650W (2.2hp) to 2200W (2.9hp). That's power consumption, not output. If you figure the motor is 80% efficient, then that puts you at around 1.76 to 2.3hp output. Anything bigger than that and your going to start blowing breakers.

It's just a guess, could also have something to do with how the motor is wound.
 
Usually motors require about 3 times the start current than the do running. The advantage of 220 is that since the voltage is higher, it requires only 1/2 amps. Also, since the potential from ground is 2x, the amount of kick that starts the motor is better. Ever wonder why some large motors use 440v as a stinger leg. The best efficiency is 3 phase power but it is somewhat unrealistic in a non commercial area. What you can do is use a 30 amp 220 volt circuit feeding a sub. From there, you can break off legs of 220 and 120 volts. Since not tools are running at a time, you can fuse a 12 ga feeder with 20 amps double pole, 10 ga can handle 30 amps, and 8 gauge can handle 40 amps. The neutral leg of the 220 can be 1 awg size smaller than the 2 feeder legs.
220 volts wired for a 30 or 40 amp sub breaker and broken down to 2 220v 20 amp circuits and 4 110v 15 amp circuits. Remember, 220 gives you amps on each leg.
 
A dual voltage motor (which can be either 110/220, or 220/440) is wired in such a way that the field/stator windings are divided equally in half.
In the Low voltage configuration both halves are wired in parallel. and see the full source voltage. When wired in the High voltage configuration those halves are placed in series. In either case the actual motor windings see the same voltage potential. However in practice few people provide the necessary additional gage wire to allow keep the voltage drop the same when using low voltage.
 
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