Which motor to replace 3 phase motor

[Iron-Iceberg]

I bought a small paint booth with a 3 phase motor running the blower. The motor is 3 phase, 2hp, 1740rpm.
My question is can I replace the motor with the same 2hp, 1740rpm motor in a single phase 220v or would I need more hp to run the blower? Is 2hp, 2hp either way? Any other considerations?

I thought about a phase converter but they cost more than a new motor and I don't have any other 3 phase machines, so I just want to swap out the motor.

 

[OldCarGuy]

You could consider a VFD to convert single-phase to run that three-phase fan motor. If your not planning on installing any more three-phase equipment in the future. In my opinion replacing the three-phase motor with a single phase 240Volt motor is your best option. Two HP three-phase can be replaced with a two HP single-phase motor.

 

[Iron-Iceberg]

Thanks for the reply OCG. I will probably go with the new 240v motor. And try to stay as simple as possible.

 

[helopilot]

I have been pricing motors as well. What I have found so far is I can get a new single phase motor for the same price I can get a rotary phase converter. Check out some of the companies on Ebay. They have been averaging 250-300 bucks.

 

[OldCarGuy]

You have to make sure there is an available direct replacement motor that will fit. Some of the pump manufacturers purposely make the mounting flange and or motor shaft to their own specifications. And not to any standard. Forcing you to either purchase one directly from them or have one custom modified to fit. The other option is to have the original three-phase motor re-round to run on single-phase by a motor rebuilder.

 

[CraigFL]

Also.. make sure it's a blower rated motor -- continuous operation. Usually they are TEFC(Totally Enclosed Fan Cooled) because they are sized for the HP needed to blow that volume of air all the time.

 

[Matti]

For the motors to be totally interchangeable dimensionally they must be the same frame size. For example it might be a NEMA frame size 145T which dictates the mounting dimension and the shaft size.

 

[Iron-Iceberg]

LOL, so much for "staying simple as possible." Maybe I should get an rotary phase converter, and start getting some of these deals on 3 phase lifts, compressors, ect that no on wants.

 

[Ign]

There are plans all over the 'net for building your own RPC. I think after you've done it once they'd be cake to build in the future, for whatever reason (build to re-sell, or upgrade yours if you find it's too small as you acquire new equipment)

 

[Steve in Mi]

I bought a small paint booth with a 3 phase motor running the blower. The motor is 3 phase, 2hp, 1740rpm.

On a paint booth there is a good chance that the motor is for hazardous duty or explosion proof. If that is the case a single phase explosion proof motor to replace it is going to be big $$$$.

Personally I would install a VFD (remote) on it to; 1.) use the motor that is already suited to the job and 2.) to obtain variable speed operation of the fan.