Automatic "up" limit switch for an overhead crane

An alternative 'limit switch' for an overhead crane, useful when its normal machine is broken.

The role of a limit switch is to check if the end of the safe travel distance has been reached and stops the motion. However limit switches wear out over time or its limit baffle can be damaged and needs time and money to be replaced.

This was the problem I needed a quick and cheap yet safe solution. An infrared switch or photoelectric sensor, which closes the relay when activated by the crane hook.

Normally the sensor allows the current to go to the relay and the crane works as normally. But when the winch crane hook its limit, then it simply shuts off the relay power supply and the crane can't go "up" anymore.

The photo below shows the sensor in the circle.