NPN (Sinking): When active, the sensor output connects the PLC input to ground (0V). A mismatch will not work and could potentially damage the components. The sensors can be connected directly to the fieldbus or WI180C IO-Link gateway using an internal bus connector. These are simple "on/off" sensors. This is where fiber optic communication transforms plant operations—bringing speed, reliability, and safety to industrial automation. Industrial environments are electrically hostile. Heavy machinery generates electromagnetic interference that corrupts data traveling through copper cables. Fiber. Modern Programmable Logic Controllers (PLCs) are central to industrial automation, controlling machinery, production lines, and complex processes. As automation systems evolve toward distributed architectures and smart factories, high-speed and long-distance communication between PLC modules. Before learning how to interface sensors to a PLC, it's essential to first understand the main types of sensor output signals: Digital signals (discrete/on-off): Used by proximity switches, photoelectric sensors, and limit switches. Analog signals (variable range): Used by temperature, pressure, or. Does any body know is there is any way to connect a contactor to a PLC output using an optic fiber link, without compromise the cyclical checking performed by the safety module (as I understand, the outputs are continuously check in order to detect wire breaking).