Traction Motors

[Gareth Lumsden <s9763278@minyos.its.rmit.edu.au>]

All,

What causes EMU traction motors of the same type/make to be noisier than
others?  Often parts of the carriage vibrate which aren't meant to, as a
result of "groaning" traction motors.

Some of Melbourne's Comeng "groaner" motor cars currently are:
302M
338M (no 2 end bogie)
350M
503M (lead bogie)
647M (no 2 end bogie)

Noisier motors have no effect on performance or reliability, most cars
listed above have been groaning for over a year.

I can recall some V/Line locos which also used to have louded tm's than
others of that class.

I was always under the impression that bearing/s were tighter, but it was
recently suggested to me that it has something to do with the coil.

Does anyone know?
TIA
Gareth.

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 Gareth Lumsden     s9763278@minyos.its.rmit.edu.au    glums112@yahoo.com
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 Gareth's Railway Web Page        http://minyos.its.rmit.edu.au/~s9763278
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