This tutorial gives an introduction to the HY-M154 / 817 optocoupler module. Moreover, a simple application is programmed that shows how to wire and how to program an Arduino when working with the module. Optocouplers are very useful when you need to isolate different sections of a circuit, for example in power. An optocoupler (also called an opto-isolator or photocoupler) is a component that transfers an electrical signal between two isolated circuits using light. Because the signal crosses as light —. This circuit is only applicable where the incoming signal has some information or data but when we just need to forward the signal from one part of the circuit to the other part but signal contains noise, then we could use the combination of IR sender and receive. From my understanding, when the modul receives DC current (5V), it's going to turn on the other circuit and turn on the bulb.
