doonjumper
1/2 ton status
This is a phase 3 motor. Can it be hooked up 220v. I ask because the voltage is 208-230/460. Does this mean it can be wired either 220 OR 460? http://www.electricmotorwholesale.com/BALDOR-M3212T/
CK5
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Need an electrician to answer this
- Thread starter doonjumper
- Start date
79rustyk10
3/4 ton status
220 how the average guy knows it is two phazes, so no. 208 IIRC, is three phazes of 120V, I think the 460 is three phazes of 220.
There is also the phaze converter option.
I'm not up on all the 3 phaze stuff anymore as I've only been doing residential, but I'm guessing fordum will chime in with a very descriptive answer.
There is also the phaze converter option.
I'm not up on all the 3 phaze stuff anymore as I've only been doing residential, but I'm guessing fordum will chime in with a very descriptive answer.
3 phase is 3 phase.....You can buy a phase converter to run the motor on single phase, but it won't run as efficiently.
You can wire the motor for either low voltage(208-230) or high voltage(460-480).
You'd be better off looking for a single phase motor.....
What's the motor for?
You can wire the motor for either low voltage(208-230) or high voltage(460-480).
You'd be better off looking for a single phase motor.....
What's the motor for?
doonjumper
1/2 ton status
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You can hook it up to single phase 230 volts with a phase converter[http://www.phase-a-matic.com/StaticDescription.htm]....If you have to get a new motor, just buy a single phase unit....
doonjumper
1/2 ton status
Thanks! I just sent them a converter size request.
Before you go phase converter, there may be a better way.
What size is the motor?
If its under 3 hp, there is a better way to go.
First you need to understand how phase converters work.
A static phase converter is basically a motor starter. It supplies the third phase briefly to get the motor started, then it drops out and the motor continues to run on single phase.
As a result, you only get about 2/3rds of its rated power, and it tends to run noisy and hot.
A dynamic phase converter, or rotary phase converter, is just a second motor. You tie two of each of the motor's legs to the two hot wires, and then tie the third leg of each motor to each other.
When you start the two motors, they supply the third leg to each other.
Uses more power, and you have to buy the second motor, but if its big enough it can run several other motors, and gives you almost full power.
This used to be the only way to fix this problem short of replacing the motor with a single phase motor.
But, now you have a third option.
You can buy a three phase motor drive. Its a solid state gadget that takes regular line power in, converts it to DC, and then regenerates AC at different frequencies.
Thus, you can vary the speed of an AC motor, since the speed it runs at is determined by the input frequency.
At 60 cycles, it runs at normal speed. Change that to 30 cycles, and it runs at half speed.
The reason this helps you, is because it can take single phase in, and create three genuine phase.
But, they only go up to about 3HP with single phase input at full power.
Check this link out. There are other places, but they seem to have good prices. Since you only want to get three phase out, you don't need the most expensive one. Any that will get you three phase at your horsepower will do.
http://dealerselectric.com/mfg-subcat-item.asp?cID=28&scID=165&mID=-1
What size is the motor?
If its under 3 hp, there is a better way to go.
First you need to understand how phase converters work.
A static phase converter is basically a motor starter. It supplies the third phase briefly to get the motor started, then it drops out and the motor continues to run on single phase.
As a result, you only get about 2/3rds of its rated power, and it tends to run noisy and hot.
A dynamic phase converter, or rotary phase converter, is just a second motor. You tie two of each of the motor's legs to the two hot wires, and then tie the third leg of each motor to each other.
When you start the two motors, they supply the third leg to each other.
Uses more power, and you have to buy the second motor, but if its big enough it can run several other motors, and gives you almost full power.
This used to be the only way to fix this problem short of replacing the motor with a single phase motor.
But, now you have a third option.
You can buy a three phase motor drive. Its a solid state gadget that takes regular line power in, converts it to DC, and then regenerates AC at different frequencies.
Thus, you can vary the speed of an AC motor, since the speed it runs at is determined by the input frequency.
At 60 cycles, it runs at normal speed. Change that to 30 cycles, and it runs at half speed.
The reason this helps you, is because it can take single phase in, and create three genuine phase.
But, they only go up to about 3HP with single phase input at full power.
Check this link out. There are other places, but they seem to have good prices. Since you only want to get three phase out, you don't need the most expensive one. Any that will get you three phase at your horsepower will do.
http://dealerselectric.com/mfg-subcat-item.asp?cID=28&scID=165&mID=-1
Well, I guess I could have looked at the link, but did not see it.
5 hp is a problem.
You are above the full power single phase variable frequency limit, and the next size up, is the 10 hp.
It would work, because it will operate on single phase at half power rating. So it would drive your 5 hp at full power just fine.
But, its also $643!!
A static would be better at about $230, but you will not get full power from your motor.
Rotary give you full power but at a cost of $900.
You best bet, is to find an old free or cheap 10hp or bigger 3 phase motor and make a rotary out of it.
Easy to do.
Failing that, the link you posted for the motor also sells some single phase motors in the 5 horse range.
I see a Lincoln 5 hp single phase, same speed, same service factor.
http://www.electricmotorwholesale.com/LINCOLN-LM24681/
It is a 184T mount instead of a 182T, but that only means there is a one inch difference between the mounting holes in the base.
It also draw about twice the current as the one you have now, and is only for 208-230.
But its $471, and might be the cheapest way to go.
If there are any large commercial buildings going down around you, check to see if they have some big fan motors or things like that 10hp or bigger in 3 phase that you might get for scrap price.
Then you could build a rotary converter.
Oh, and whatever you do, if you use the motor you have now, it must be wired for the voltage you are going to run it on.
There should be a diagram under the plate where the wires hook up that tells how to wire it for high or low voltage.
5 hp is a problem.
You are above the full power single phase variable frequency limit, and the next size up, is the 10 hp.
It would work, because it will operate on single phase at half power rating. So it would drive your 5 hp at full power just fine.
But, its also $643!!
A static would be better at about $230, but you will not get full power from your motor.
Rotary give you full power but at a cost of $900.
You best bet, is to find an old free or cheap 10hp or bigger 3 phase motor and make a rotary out of it.
Easy to do.
Failing that, the link you posted for the motor also sells some single phase motors in the 5 horse range.
I see a Lincoln 5 hp single phase, same speed, same service factor.
http://www.electricmotorwholesale.com/LINCOLN-LM24681/
It is a 184T mount instead of a 182T, but that only means there is a one inch difference between the mounting holes in the base.
It also draw about twice the current as the one you have now, and is only for 208-230.
But its $471, and might be the cheapest way to go.
If there are any large commercial buildings going down around you, check to see if they have some big fan motors or things like that 10hp or bigger in 3 phase that you might get for scrap price.
Then you could build a rotary converter.
Oh, and whatever you do, if you use the motor you have now, it must be wired for the voltage you are going to run it on.
There should be a diagram under the plate where the wires hook up that tells how to wire it for high or low voltage.
doonjumper
1/2 ton status
Thanks for the info! I have access to a scrapyard and will be on the look out for a 10Hp motor. In the meantime I will put this motor on Craigslist and try to sell it. If it sells then I'll use that money towards the new Lincoln.
One question though....approximately how much power would a 3 phase stacic drive supply my motor if I went that route?
One question though....approximately how much power would a 3 phase stacic drive supply my motor if I went that route?
Ok, one thing to remember. There is no such thing as a static converter. I know that there are things out there called that, but they do not convert anything.
All they are, is a fancy type of motor starter. You can build one out of a push button and a capacitor.
A three phase motor will run on single phase, it just will not start on it.
So the converter supplies a quick shot of phased voltage to the third leg to start the motor spinning.
Then the motor continues to run on the other two legs.
BTW, that quick shot is all that is available. It just pretty much dumps the capacitor across it.
If you leave the starter hooked up, it will either burn up the capacitor, or just not do anything.
So, to answer your question, in theory, you will get 2/3rds as much power as you should, since you are only supplying it with 2/3rds of the electricity it needs.
So, that 5hp motor should put out 3.33hp. I would knock off the .33, because 3 phase motors are just not happy on single phase, so there are heat and vibrational losses.
In looking for a 10hp, remember that it has to be the same voltage and 3 phase. And that you will run it and the 5hp at the same time.
But, it will give you full power out of the 5hp.
All they are, is a fancy type of motor starter. You can build one out of a push button and a capacitor.
A three phase motor will run on single phase, it just will not start on it.
So the converter supplies a quick shot of phased voltage to the third leg to start the motor spinning.
Then the motor continues to run on the other two legs.
BTW, that quick shot is all that is available. It just pretty much dumps the capacitor across it.
If you leave the starter hooked up, it will either burn up the capacitor, or just not do anything.
So, to answer your question, in theory, you will get 2/3rds as much power as you should, since you are only supplying it with 2/3rds of the electricity it needs.
So, that 5hp motor should put out 3.33hp. I would knock off the .33, because 3 phase motors are just not happy on single phase, so there are heat and vibrational losses.
In looking for a 10hp, remember that it has to be the same voltage and 3 phase. And that you will run it and the 5hp at the same time.
But, it will give you full power out of the 5hp.
doonjumper
1/2 ton status
Great advice thanks!
with a rotary phase converter you will still need the appropriate contactor and capacitors. plus the wiring diagram to set it up. I used to build them when i worked in the rewind shop. complicated to build but work well. Hers some pics of one I found
I've built several rotary phase converter without any start/run caps used. Here's a 10 hp I have now, I've started a 30 hp idler for another project. My shop has a 5 hp air compressor and two grinders all three phase powered. Everything I have was bought used/surplus for parts.
Click for video-
Click for video-
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220 is still single phase. It's one leg of 480 (277V roughly per phase) run through a center-tapped transformer. If it was "two phase", it would be 33* out of phase rather than 180* out.
That is the nice part about using a second motor, or a rotary converter, same thing.
You are running them off 3 phase, because they are generating the third phase.
Actually there is a couple of degrees phase difference from powerline 3 phase, but the motors don't mind.
CGT80
1/2 ton status
The only 3 phase tool I run is my Baldor 1/2hp grinder. I bought a VFD for it and run it on 120v so that I can move it if needed. The amperage draw is very low on this motor anyway. It runs great on the VFD. $120 for the VFD and the grinder was free and in very good condition. The grinder is $400+ when new.
For that saw I would either install a new motor that is 240v single phase or run a rotary phase converter if you plan to run additional 3 phase motors.
For that saw I would either install a new motor that is 240v single phase or run a rotary phase converter if you plan to run additional 3 phase motors.
doonjumper
1/2 ton status
Would this work as a rotary converter?
Should work.
There are lots of diagrams on the web about building the converter. You can go as low tech or fancy as you want.
At it's most basic, you can just tie a rope to the shaft of the idler motor, pull start it, and then throw single phase power to it.
It will start running poorly.
When it gets up to speed, tie in the work motor.
It will start, and the idler motor will even out because they will start suppling the third phase to each other.
You have to be sure to not put power to the idler motor until the rope clears the motor shaft.
Even with single phase, you are dealing with a powerful motor and if the rope gets caught, it will suck you in.
Run capacitors will clean up both motor's running.
This is a pretty good writeup.
http://www.waterfront-woods.com/Articles/phaseconverter.htm
I would not bother with the starter relay unless you just want to. That last schematic is fine.
Make sure you have a positive cutoff on the power going to the system.
There are lots of diagrams on the web about building the converter. You can go as low tech or fancy as you want.
At it's most basic, you can just tie a rope to the shaft of the idler motor, pull start it, and then throw single phase power to it.
It will start running poorly.
When it gets up to speed, tie in the work motor.
It will start, and the idler motor will even out because they will start suppling the third phase to each other.
You have to be sure to not put power to the idler motor until the rope clears the motor shaft.
Even with single phase, you are dealing with a powerful motor and if the rope gets caught, it will suck you in.
Run capacitors will clean up both motor's running.
This is a pretty good writeup.
http://www.waterfront-woods.com/Articles/phaseconverter.htm
I would not bother with the starter relay unless you just want to. That last schematic is fine.
Make sure you have a positive cutoff on the power going to the system.
