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Unread 30-01-2011, 17:36
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Ether Ether is offline
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Re: Stalling the BaneBot 775 motors

Quote:
Originally Posted by Al Skierkiewicz View Post
I am simply suggesting that an estimate of power dissipated can be made if one ignores rise time for this discussion.
If you "ignore rise time" and assume that "full power is being applied during the pulse" you will get a very wrong answer if your assumption is wrong.

I do not know what the inductance of the RS775 is, but even if it is as small as 20 micro Henries, then power consumption at 20% duty cycle (with a Jag and locked rotor) will be roughly 40 watts, not 213.6 watts.

If anyone reading this has access to the necessary test equipment and would be willing to measure locked-rotor inductance of the RS775 and post the result here, I will run a simulation and post a graphic of the current waveform (and power calculation).




Last edited by Ether : 30-01-2011 at 18:50. Reason: typo