4 Channel LDR PLC Driver

The PCB's came in just as expected great quality and on time. This project will take a variable light level and product a +24V/Ground signal when the light level is above or below a set value. This output can be fed directly into a WAGO digital input module on the PLC. In my case this is used on a model railroad to indicate when a locomotive is fully in the round house. It will then remove power from the track to prevent the locomotive from running into the building. It can be used for other detection such as noting when a train passes a point and triggering and event such as flashing lights or triggering a sound event.