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Robert Swinney
 
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"Adam Smith" wrote in message
...
I don't understand how the motor could be driven by the generator, I'm
afraid. Wouldn't there need to be some kind of loop for that to happen? I'm
contemplating a situation were the generator would not have any electric
feed lines, would simply be mechanically driven. I would have guessed the
effect of driving the 1740 generator at 1725 would be to produce 59.48 hz
power, but I may (probably) be missing something.

I'm not at all determined on this, my current situation is not very
broken. If you and Bob come back and say I'm crazy to think of this, I'll
just balance to the vertical mill, and let the horizontal and shaper be
under-balanced.

Thanks,

Adam


Adam, your concerns are with respect to the afore mentioned induction
generator. Speeds such as 1740 and 1725 are not
absolute. Induction motor speeds vary slightly with loading and are stated
on a motor's nameplate with respect to the rated HP. Check into induction
generator theory before making any such speed / voltage calculations.

Bob Swinney




wrote in message
oups.com...
NO! You should not drive the 25 hp motor through a Lovejoy. You need
to drive the 25 hp using a belt drive that is adjustable. The reason
is that if you drive it with a Lovejoy, you may or may not be actually
driving it. Say the RPC with no motor driving it turns at 1740 rpm and
your 10 hp motor runs at 1725. Then the RPC will be driving the 10 hp
motor.

If you do connect the RPC and a 10 hp motor with an adjustable drive,
you can measure the current going into the 10 hp motor and adjust the
drive so that the current is at or somewhat below the rated nameplate
current. It will then be driving the RPC slightly faster than the RPC
would turn at on its own. And life will be good 8-).

Dan


Adam Smith wrote:
So: I'm asking myself if I should balance the RPC (and if so, to which
load?). Or if I should just get one 10 hp single phase motor, drive the
25
hp through a lovejoy, and make true 3 phase. Which would probably make
any
future 3 phase equipment happier, (ie CNC stuff, welders or plasma,
anything
that is fussy about its power).

Comments?

Thanks,

Adam Smith
Midland, ON