I have a bandsaw motor which can be wired for 220 volts. The bandsaw has a magnetic on and off switch. Do I need to change the wiring of the switch as well as the motor?
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Replies
Would not know for sure without knowing how your machine is wired, usually all you have to do is select 220 on the motor, but all manufacturers can use different motors, switches, or starters.
Call the company, and hire an electrician. 220 is more than twice as dangerous as the fizzy feeling from a 110 zap. Not worth your ass, not worth risking the machine. Reality checks get paid sometimes.
Has there been problems running the saw on 120 volts? If you haven't been tripping breakers, there won't be any improvement in performance by switching to 240.
Hello. I agree with the above post. If it is working at 120 why not leave it? BTW, some folks think its cheaper to run a motor at the higher voltage, not true. While the voltage is doubled, the amps are halved, which equals the same wattage- which is how you bill is determined. Anyway, I wish I could answer your original question, but its not really possible without taking it apart and looking, you would need a double pole single throw for the 220. While a single pole will stop the motor, it is not safe or legal to do it that way.
xylie6 is dead on correct. The only advantage would be taking the load off of the 120 volt circuit it is connected to. If you are running another machine or lighting at the same time as the band saw on the same circuit you could possibly trip the breaker on overload. I run my band saw on 120 and my dust collector on 220 for this reason even though I could rewire the band saw for 220.
I appreciate all of the responses and those regarding my safety. Yes I understand that the HP rating of the motor does not change going from 110 to 220. However, I am doing more and more resawing and want the motor to run cooler on 220 volts. I was of the understanding that because there is less amperage draw the motor would run cooler, Yes?
You will have to change the switch also. 220 VAC has 2 hot switch leads. 110 VAC only has 1 hot switch lead. Also running on 220 makes the motor more efficient. Every time I can run 220 I do. Do it your power panel has the space.
A lot of tools are convertible between 120 to 240. No changing of switches or anything else. Wiring instructions are usually printed on or inside the motor housing. You should also becable to find the manual online, if you dont have it. If its possible to do an easy switch, theyll tell you how.
I changed a radial arm saw to 240 many years ago, and a table saw maybe 10 years back. The change was very simple, clearly outlined, and required no parts.
If yours is not clearly delineated, or if you have changed the switch or motor from the factory configuration, you really should call an electrician.
Another consideration is the panel.How far away, are you able to run the new circuit, is there enough room for the new breaker, are you ok installing it?
You could also call for an estimate or bribe an electrician friend or relative. Of course you could likely get it done yourself, but someone who does it for a living knows things that just take experience to learn.
I was in the orange store yesterday, and walked past the wire in electrical. I remember when #12 was $40 per 1000 ft. A single #14 (500') was $38. The cost of material is a real consideration now.
Let us know what you decide and how it goes.
Increasing the voltage to 240V will reduce the line current to about half. This means the line supplying the motor can be reduced in size but the minimum wire size allowed is #14. If you are already using #14 wire, there is no advantage. But, if the circuit breaker is tripping out then you could connect the motor to a 120V, 20A circuit. Remember though, you cannot just replace the 15A breaker without first making certain that the branch circuit wire size is correct. For a 20A breaker you should probably use at least #12 cable.
Also, the typical type of single phase motor that you probably have (capacitor start, induction run) shows no increase in starting or running torque with the increase in voltage. So the only advantage to rewiring the motor and increasing the voltage to 240V is the reduction in line current. If you require greater torque you must change the motor to one with a higher horsepower rating or use a different type of single phase motor. (ie. capacitor start, capacitor run)
Whether the switch is wired 120V or 240V depends on the manufacturer. It is much safer and more common to use a single pole, momentary contact switch using 120V.
Regarding the motor running cooler or not; it won't run cooler. The amount of horsepower and torque are similar. You will need to use an external means to cool the motor. ie. more air flow and keep the dust and dirty out of the motor vent holes.
Michael Fortune, a real band saw expert uses a 14 inch old General (made in Canada) band saw for all his needs, including re-sawing. If your motor heats up with use at 120V, why would it not heat up using it at 240, if the wattage used is the same?
Michael Fortune, a real band saw expert uses a 14 inch old General (made in Canada) band saw for all his needs, including re-sawing. His motor is 3/4 HP only. If your motor heats up with use at 120V, why would it not heat up using it at 240, if the wattage used is the same? If it is heating up, maybe a tune-up would help, could also check wheel and blade guide bearings, to see if something correctable is making it heat up.
Yes, you would need to have a 240 volt coil for the contractor instead of a 120 volt one, or the starter would need a control transformer with dual input voltages (very unlikely).
Your motor will not run cooler on 240 volts, the motor losses will be identical.
Your motor is probably rated for a 40 or 50C rise, far too hot to hold at normal running temperatures.
Does the motor require 4 wire hookup for 220V or 3 wire hookup? If it uses 3 wire hookup it will be the same as the 110V and the switch will work as wired. The 4th wire is the neutral and would require a double pole switch.
I switched my General band saw over to 240 v because my shop was overloaded and when resawing I would sometimes trip my whole shop out !
When I moved in the past owner had a GFI outside for a hot tub but I had no tub so I brought it in put a sub panel on my wall wired two extra duplex recepticles at 120 v and two duplex recepticles at 240 v my jointer was already wired to 240v and I changed my Delta table saw over to 240 v as well so I now had 3 tools at 240 v .
I noticed an immediate jump in starting on All machines but this could have been caused by voltage drop on the old voltage, I also feel my motors are running cooler, I think they are better on the higher voltage but no proof of it. As a retired electrician I would still recommend the higher voltage as this reduces the start up current to half which over time could increase the life of your motor.
Hi Ron you have some good remarks but I wanted to point out that circuit breakers have a double component, over current , and over temperature. If you’re doing a lot of ripping the temperature element might cut in. also someone else mentioned that by just changing to a 20 amp breaker might not be the safest thing to do as as your circuit wire might be #16, which would be under rated should be #12
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