Thread: Fisher Price Breaker Size
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Unread 05-02-2009, 22:39
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Re: Fisher Price Breaker Size
Quote:
Originally Posted by DavidB View Post
Well I believe we are using three. One will be for our lift system. So It will be spinning relatively fast but nowhere near free spin. The other two will be spinning faster but not constantly. The main one I'm concerned about is our lift system one. I'm thinking about moving it a 30 amp breaker since it will probably get hot.
If your using three FP you will not be in compliance with the rules.

If an FP gets hot you're in for trouble. These are fan motors. When they get a bit too hot the plastic fan starts slipping and fails to spin making it even hotter. You may want to consider additional cooling.

The peak power point on the FP is 40 amps at 7500 RPM. I would say that you can safely operate at this point only at 7500 RPM and with additional cooling. If you trip this breaker at lower RPM then you are geared too low.

30 amps is probably a good sizing. It's best to make sure that you are geared such that the motor runs between 7500 and 15000 RPM and that when loaded it does not fall below 7500.