I have a question for all you "Engineers" out there! lol

[jjdward]

I was given a squirrel cage fan but it has no motor. I have a motor that goes on an air compressor but it will run the fan for a while and then kicks a breaker. I know there is nothing wrong with tht motor cause I just took it off an extra compressor I have. So I thing the RPM's are too high so I need a motor with low RPM's but a lot of torque. Any ideas on what kind of motor I might be able to salvage? Someone had sugessted a washing machine motor, but I have my doubts. Just thought I'd ask.

 

[wattsjadajoe]

Do me favor...(I've been an Electrician all my life) Could you list all the information on the motor tag? Then list the size of the drive pully (Motor) and fan pully? Then post a picture, I might be able to help.

Joe

 

[jjdward]

Quote:
I'm at work at the moment (don't tell my boss!!! lol) but when I get home, I'll be sure to do it!!!.

 

[wattsjadajoe]

I will check it out and get something back on here for ya...good or bad..

Joe

 

[jjdward]

Thanks! I wouldn't even mind buying a motor but I just need to know what kind of motor to buy.

 

[wattsjadajoe]

Any more info on the motor?


Joe

 

[jjdward]

Quote:

I did forget to measure the pulley lol!!!!

 

[wattsjadajoe]

Just as I thought, you have a 3600 rpm motor. It probably has a 2 or 3 inch pully and the fan would have a 6-8 inch pully. This is going to make the fan trun at approx. 14,000 rpms.

The motor has starter windings inside for starting, and once the motor comes up to speed the centrifical contacts inside the motor changes the windings to the run windings, which uses less current.

So I would say that the motor is using the starter windings, since it nevers gets to run speed, causing this to use excessive current.

You have 2 options: install the same size pully on the fan and motor, which is cheaper, or purchase a low rpm motor. Also keep in mind, even if you get a low rpm motor (1700rpm), using the same size pullys will cause the motor to work extra hard (Approx 6,000rpms).

My suggestion would be to get a pully larger than or the same size as the fan....or swap the pullys form the fan and motor.

Hope this helps.


Joe