120v or 240v for a tile saw motor

[JoeNorm]

I have a contractor that says he usually runs his tile saw at 120v but would like to run it at 240v for his coming job. The nameplate says it can be either.
My question is whether I have to change anything internally or is it as simple as making the white wire a hot wire?

My knowledge of motors is not great. Thanks for the input.

 

[kwired]

I have a contractor that says he usually runs his tile saw at 120v but would like to run it at 240v for his coming job. The nameplate says it can be either.
My question is whether I have to change anything internally or is it as simple as making the white wire a hot wire?

My knowledge of motors is not great. Thanks for the input.

If it is 1 HP or less probably not much to gain in most cases unless you are also dealing with a long circuit run. JMO.

But not as simple as making the white wire a hot wire. You need to reconfigure the motor winding connections. At 120 volts they are in parallel, at 240 volts they are in series, motor connection diagram tells you what goes where for each configuration.

 

[JoeNorm]

Thanks, I was pretty sure something internal would have to change but not 100%

I will tell him to just keep it at 120v

 

[ActionDave]

Should be information on the motor nameplate on how to switch the voltage to 240V. You would be changing the windings so they are in series.

I agree with kwired. There's no good reason to do this.

 

[herding_cats]

You would reconfigure the motor winding leads. That diagram should be on the nameplate, showing the simple schematic by color of wires bonded or connected to line, or terminated differently or by number. If he is taking the saw to jobsites with long extension cord runs maybe there is a benefit.

What is the reason he wants 240vac?

Maybe only 240v is available in the work area? Like maybe he plans to pinch on to an AC disconnect temporarily for the job?

 

[ptonsparky]

Why? Possibly because it trips the GFCIs and he thinks to avoid them by changing to 240.

 

[herding_cats]

Why? Possibly because it trips the GFCIs and he thinks to avoid them by changing to 240.

Good point. Probably. Or AFCI if in a residential remodel. Interesting.

 

[retirede]

He also may have had problems tripping breakers on startup. My chop saw had this problem until I installed a QO hi-mag breaker.

 

[kwired]

Why? Possibly because it trips the GFCIs and he thinks to avoid them by changing to 240.

Probably has poor condition cords or switch/motor full of water presuming this is a wet tile saw?

Or the site has cheap no name GFCI's? Only electronic speed controlled power tools give you much troubles with GFCI tripping otherwise, if this is a dual voltage motor it probably a basic capacitor start motor and those generally don't give much for nuisance trip problems.

 

[Sberry]

I have larger table saw and it hasnt given me greif on 120. When I was a kid I was going to "change " it because I could. Because we font knowew ther best idea is to ask "why" first. Is it a brain fart or is there a problem?

 

[kwired]

I have larger table saw and it hasnt given me greif on 120. When I was a kid I was going to "change " it because I could. Because we font knowew ther best idea is to ask "why" first. Is it a brain fart or is there a problem?

One guy I work around frequently that is a carpenter, and pretty good at finish carpentry, has a miter saw with an electronic control to turn his shop vac on automatically for dust collection when he starts the saw. He can't use it on new construction if AFCI's are already installed, it trips when it tries to start that vacuum through that electronic control. I think it works at least most the time on GFCIs but if on AFCI or dual function it will trip pretty much every time.

 

[JoeNorm]

I don't know why he wants to switch it. But my guess is that he has tripped breakers/AFCI in the past and thinks this will help.