The difference between photoelectric switch and photoelectric relay

The photoelectric switch is a light pulse radiated by the light-emitting tube GL after the modulated pulse generated by the oscillating circuit passes through the reflection circuit. When the measured object enters the range of the light receiver, the reflected light pulse enters the photosensitive transistor DU. And in the receiving circuit, the optical pulse is demodulated into an electrical pulse signal, and then amplified by an amplifier and synchronized gating and shaping, and then the interference is eliminated by digital integration or RC integration, and finally after a delay (or no delay), the driver is triggered to output the photoelectric Switch control signal.

Photoelectric switches generally have good hysteresis characteristics, so even if the detected object is swayed in a small range, it will not affect the output state of the driver, and it can keep it in a stable working area. At the same time, the self-diagnostic system can also display the light receiving status and stable working area to monitor the work of the photoelectric switch at any time.

The working principle and characteristics of photoelectric relay. A relay is an electronic control device, which has a control system (also called an input loop) and a controlled system (also called an output loop). It is usually used in automatic control circuits. It actually uses a smaller current to control a larger An automatic switch of electric current. Therefore, it plays the role of automatic adjustment, safety protection, and conversion circuit in the circuit.