Re: [CAD_CAM_EDM_DRO] New Book Needed

Joe Vicars wrote:

> I am looking for a book that probably hasn't been written yet.
>
> "The scroungers guide to electric motors"
>
> This book would contain information on all types of motors, how to
>
> identify them by number of wires, coil resistances, frame sizes, etc.
> Identifying motors WITHOUT any manufacturers info, nameplates or
> anything else.
> It would also include info on how to put them back in service
> without producing clouds of smoke. What will and won't work, etc.
> etc.
> Can this be done? Does such a book exist? I will pay!!

This could be quite an effort (for both the author and the
experimenter).
There are so many types of motors - do you know the difference between
cumulative compound and differential compound? How about the purpose
of commutating poles? Armature reaction? Specific heat and the
incredibly
difficult task of computing heat flow from the armature to the exterior
of
the motor?

It just goes on and ON and ON! I took 2 full-semester courses, one on
DC machines and one on AC machines. They were just BARELY able
to cover all the detail in that time. But, in about 2 weeks in class,
you could
learn how to measure things like the cross sectional area of the field
poles,
the air gap, the number of turns on the armature and field, and compute
the
instantaneous performance of any motor within 15% or so. The only one
that
is really difficult is to determine how hard you can push the motor
without
burning it up. Even the pros have to test their designs with
thermocouples,
because there are just too many variables.

At the time I took this stuff, I really didn't expect it to be of much
use, but
since I end up tinkering with servo drives a lot, it has come in REAL
handy!

A good EE course book on DC machines would give you the background
to recognize most of what you are looking at, and know the possibilities

for various types of motors from some of the external features. But, to
really
know a motor, you have to take measurements on a test stand.

Jon