simply:
Optical encoders are vulnerable to three kinds of damage 1. The
optical disk may shatter during vibration or impact. 2. The bearings fail due to stresses. 3. Oil, dirt, or water get inside the
encoder due to seal failure. Most styles of
encoders come sealed from the factory. Over time temperature cycling causes pressure changes and seals fail, which creates a path to the inside of the
encoder. Often, the cause of the problem is moist air which enters the
encoder and then condenses, rains...
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