[FTC]: Problems with Motor Encoders?

Other FIRST Tech Challenge
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Hey Guys,

Our team is encountering some big problems when it comes to the motor encoders on the 12V DC drive motors. It seems that the brass/copper thing the encoder collar is mounted to spins freely when it should be stationary. We have tried multiple encoders on multiple motors and they all have the same problem. The spinning encoder allows for inaccurate readings and allows the encoder wires to get chewed up in the gears. 

 Has any other team encountered this same problem?
 What can we try to do to fix the problem?
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I do believe that the brass ring actually supposed to rotate freely but the encoder itself is not supposed to. The following link is the document on proper encoder assembly. http://www.education.rec.ri.cmu.edu/content/events/ftc/common/docs/encoder.pdf

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The bottom of the encoder is supposed to be covered with a sticky adhesive (kind of like a label) and is covered with a piece of plastic-coated paper, if I recall correctly. Make sure you remember to remove the paper and stick the encoder onto the motor properly (as per the instructions).

Also, be careful with those encoder cables – they’re delicate. We managed to pull one of the ends off of one of ours – so we can’t use it any more. (We don’t have the budget to buy another one and have it shipped all the way up here, anymore, either…)

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