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Unread 28-03-2010, 17:37
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Re: Ball posession: Roller (ball magnet) or vacuum?

Quote:
Originally Posted by robself705 View Post
We are geared to the fisher prices at I think up by 3:1. We get around 15,000 rpms at the vacuum impeller.
Are you running the motor at 100% PWM? If so, those numbers don't add up.

The no-load speed of the fisher-price is approx 15,700 rpm.

So if you are geared up 3:1 and you are getting only 15,000 rpm at the impeller, you are running the motor at 5,000 rpm which is less than 1/3 its max speed. This is way outside the acceptable operating region for continuous operation. At 100% PWM (12 volts) and 5,000 rpm, the motor would be drawing almost 48 amps.

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