Below is the issue I am facing, any help would be really appreciated. Please note I am a rookie in the field of electronics so forgive me if I haven't provided enough information, I am happy to provide any additional information.
I would like to use a RaspberryPi to open a door by controlling the doors buzzer.
As soon as I connect both wires of the buzzer to the optocoupler, the buzzer activates, regardless if the RaspberryPi (the LED) is on or not.
It is my understanding however that the buzzer should not activate until the RaspberyPi is on. I.e. the problem is, is that the buzzer's circuit closes as soon as I connect it to the optocoupler.
A RaspberryPi and a door buzzer circuit are coupled together using this optocoupler. By turning on a pin on the RaspberryPi, the LED lights up and the optocoupler should close the buzzer's circuit.
What I have tried
- Instead of the buzzer, I have used an LED (power source and ground are provided by the RaspberryPi using a different pins. In this case, the optocoupler works as it excpected; i.e. the LED replacing the buzzer will only light up if the RaspberryPi's LED is on.