110 verses 220 motor supply

DWatson

DWatson

Member
Hey guys, just a quick question about voltage supply. What is the major difference in running a grinder on 110v or 220v? I have both in my shop, but am unable (for some reason) to get my Baldor 1 hp wired for the 220 v. I have it wired for 110 v, now and it works fine. Is there a need to worry about setting it up for 220 or will things be fine as is.
By the way, with it running on the middle position on the 3 step pulleys, I can't bog it down at all, runs beautifuly, IMHO.
Thanks for the feedback... Darrell
 
If it works fine on 110, then there's little reason to change it IMO. Especially for such a small motor and what I'm assuming is a short run of power cord. The only real advantage to running 220VAC in this instance is that you'll draw less current (about half of what you're drawing with 110 to be precise).

As for the wiring between the two, as long as it's a 110/220 motor, there should be a wiring diagram on the nameplate or inside the wire box on most dual voltage AC motors. It's just a matter of following the wire numbers and pairing them properly.
That being said, if you're uncomfortable/unsure of how to do this, I wouldn't recommend messing with it. 220VAC can bite hard.
 
If it runs fine on 110v, then it should be OK. The biggest difference is that on 220v, the motor will draw 1/2 the amps it does on 110v. This comes into play if the breaker/fuse that motor is connected to is close to the rated amps of the motor....say for example your motor draws 13 amps, and it's hooked to a 20 amp breaker.....in some situations, when you put a lot of load on the motor, it could trip the breaker (as you apply load the amps used by the motor will spike). If you were to wire the same motor for 220v, it would draw something like 6.5 amps.

For years I ran my Square Wheel grinder on 110v, and was always tripping 20 amp breakers......after rewiring it for 220v.....never have tripped a breaker. Many times you will hear folks say that a motor will run "stronger" on 220v, but I suspect it's just the fact that the motor uses less amps, and therefore doesn't "bog" or trip breakers.
 
EdCaffreyMS said:
If it runs fine on 110v, then it should be OK. The biggest difference is that on 220v, the motor will draw 1/2 the amps it does on 110v. This comes into play if the breaker/fuse that motor is connected to is close to the rated amps of the motor....say for example your motor draws 13 amps, and it's hooked to a 20 amp breaker.....in some situations, when you put a lot of load on the motor, it could trip the breaker (as you apply load the amps used by the motor will spike). If you were to wire the same motor for 220v, it would draw something like 6.5 amps.

For years I ran my Square Wheel grinder on 110v, and was always tripping 20 amp breakers......after rewiring it for 220v.....never have tripped a breaker. Many times you will hear folks say that a motor will run "stronger" on 220v, but I suspect it's just the fact that the motor uses less amps, and therefore doesn't "bog" or trip breakers.
Click to expand...

Ed is correct, set for 230v the motor will draw less amperage. The motor will probably last a little longer on 230v but you should get years and years of service with it wired for either. The real problem is the amperage required to start the motor. Once it is started the amperage goes way down. Years ago I had an air compressor about a 100 yards from the house and the breaker box. It was wired for 115v and when I would plug it in I could hear that it was having a hard time getting started. After it got started it ran fine, until it needed to start again. After replacing 2 motors I learned about the amperage issue, changed it to 230v and never had another problem.

As to the cost savings, the amperage required to run the motor is about half but you are using two legs so if on 115v it draws 13amps and on 230v it draws 6.5 amps per leg you are still drawing a total of 13 amps. There is some money savings but not half as much. If you check the actual draw (in dollars) for the motor you will find that it does not cost a lot to run a motor so if the reason for using 230v is to save money you would have to be running a dozen motors 24 hours a day to really realize a savings. Besides, the plugs, etc cost more and if you have to run a new circuit (and hire an electrician) you will never recoup the cost.
Bigger motors do draw more amperage so if you are running a 2 hp motor or bigger it may be necessary to go with 230v, especially if you are running one of the KBAC 27D VFDs.
 
Thanks guys for the info, the motor is running on 110v, 12 guage wire, independant circuit with 20 amp breaker. I tried to use the diagram on the face plate for 220 hook up, but my lack of knowledge in this area prevented me from doing it succesfully. I had 220 coming from my 220v double pole switch into the motor, but the motor would do nothing. Wiring it to 110v, got it running fine, (with a single pole 110v switch). Although I havent had a chance to use it for its intended purpose yet, just grinding scrap steel, i was not able to bog it down nor has it tripped the breaker, (yet, lol). I suppose I will heed the advise given and just leave it as is with 110v untill I run into breaker problems, ( if ever). If I do decide to go 220v, I will get someone qualified in that area to do it, as I obviously am not.
Soon as I get it finished, cleaned up and painted, I will post pics, thanks again......Darrell
 
As a dual voltage motor consists of three windings, two run and one start, and as the run windings are either in parallel for 110V or Series for 220V and the start winding is in parallel with one of the run windings, all of the windings see is 110V.
Since each winding will draw the same amount of current based on its using 110V and the power that the motor consumes is identical in watts (volts x amps = Watts) and based on this it does not matter, either from a starting or a running stand point whether you wire the motor 110 or 220V.
The total amperage in the wires that feed the motor start to get above 15A which most common household circuits can handle. If we run the same motor on 220V, even though the total power in watts is the same, it is now split between two current carrying conductors, at say 7.5 Amps each so that smaller wiring and smaller breakers can be used. It also balances out the current load on the main panel better.
 
I have nearly everything running on 220, more stuff can be running on the same circuit without worrying about tripping a breaker. It may start up a little better if your pushing the amps. No energy savings since your still going to use the same amount of wattage. It is true your pulling half the amps but on two different legs so you still use the same energy.

If it's doing fine on 110 then you'll be ok.
 
You must log in or register to reply here.
Back
Top