From sun sensing to feedback, limit switches and safe controller behavior.
Reference signal
Some trackers use sun-position algorithms, light sensors or both. Direct irradiance sensing needs filtering to handle clouds and temporary shadows.
Motion feedback
The controller must know whether requested movement happened. It can compare a commanded position to an actual position sensor, with acceptable error bands and timeouts.
Safety
Travel limits, over-current detection, manual override and a documented fault state are fundamental safety considerations for moving equipment.
Test before deployment
Prototype sensors independently and validate all error conditions before coupling the controller to a large moving panel array.
Educational information only. The suitability and safety of a retrofit depend on a site-specific engineering review.