Electric Motors - Fans - blades

[MrReds]

Hallo to everybody !
Please, I am looking for a book, or some publications, or some pdf files, where I can find some information concerning electrical motors utilized in refrigeration applications, and how they work.
For example, the motors of the fans (internal or external rotor), or the motors of the compressors.
Moreover, does anybody knows a practical handbook - or suggestions - for knowing how to recognize if the sense of turning of a blade of a fan, or the motor of compressor is correct or not - that is: have I connected correctly the phases -?

Thanks in advance !

[Peter_1]

Most commercial compressors can run in both ways.

For a fan, you have to look to the blades and how they're shaped. A fan blade is rarely a flat blade and has almost allways a curved pattern. You must try to imagine how the air is picked up by the tip fan blade and then pushed by the blade, following the curve of the blade (difficult to explain if you haven't a real model in front of you)

[MrReds]

Many thanks Mr. Peter.
Please, just a clarification concerning the air direction issue.
Is kind of imaging a point that is picked at the tip of the blade that after moves towards the shaft ?

Please, may I ask you if you know any publication or web site where I can find a clear definition for motor with external rotor and motors with internal rotor ?

Thanks in advance

[Peter_1]

http://www.ebmpapst.us/techarticles.asp

http://www.flaktwoods.com/

http://www.feta.co.uk/fma/

http://electronics.howstuffworks.com/motor1.htm

One of the best and free to download
http://www.ibiblio.org/obp/electricCircuits/

[monkey spanners]

For a basic guide to the working of electric motors i found 'Electric Motors by Jim Cox' very helpful.
ISBN 0-85242-914-2
It covers many of the types of motors found in refrigeration systems.

Cheers Jon

[Brian_UK]

There is also an E-book here
http://www.schoolscience.co.uk/conte...per/index.html