On Fri, 30 Nov 2007 21:02:07 -0500, Wayne.B
wrote:

On Wed, 28 Nov 2007 10:26:59 +0700, Bruce in Bangkok
wrote:

A train engine will increase RPM as the electric load goes
up.


I guess I assumed that because they drove a "generator" that they were
generating A.C. .

They probably are but then rectify it to DC at some point like an
alternator. If so, the RPMs/frequency do not matter.


Years ago I had a train guy, who didn't understand it very well, try
to tell me about how an electric locomotive worked. He was a bit vague
about 'lectricity but did talk a lot about some sort of coils or
resistance grid on the top of the engine that got very hot under
certain conditions.

Bruce-in-Bangkok
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