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Unread 05-07-2012, 09:22
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Richard Wallace Richard Wallace is offline
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Re: CIM Motor Failure

Quote:
Originally Posted by Brandon Holley View Post
Al-

Does the failure of a CIM due to overuse/abuse have any key indicators we can note externally (ie: while still mounted to the robot)? Or is it a slow decrease of output power over time that eventually becomes noticeable.

-Brando
Quote:
Originally Posted by Al Skierkiewicz View Post
... The failure exhibited above is kind of a domino effect. As the motor builds excessive heat the insulation on the windings starts to break down. When that occurs the windings start to short. This causes the current to climb while the output power falls.
Brandon, I know you asked Al, but let me try. Al's post above indicated a possible in-situ diagnostic, namely motor current. If the motor is drawing more current while powering the same load (i.e., while the robot is performing the same operation), then it is either hot or starting to fail, or both. Allowing the motor to cool for a while, say an hour, and then repeating the same robot operation while observing the current will tell you whether the motor was merely hot, or failing.

Jaguars with CAN provide one method of monitoring in-situ motor current. WildStang published another method many seasons ago.
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Richard Wallace

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I believe in intuition and inspiration. Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution. It is, strictly speaking, a real factor in scientific research.
(Cosmic Religion : With Other Opinions and Aphorisms (1931) by Albert Einstein, p. 97)