Hello! This is my first post here. I will start by saying that I don't know a lot about electronics and electricity so forgive me if I say something that does not make sense.
I am trying to figure out how to drive a relay with the output of a voltage converter. Please take a look at the diagram attached. The top part shows my current setup for converting the 24VAC voltage from the source I am working with (the boiler in my basement) to 3.3VDC. I'm using a voltage converter I found online and it's working perfectly (checked the output voltage with a multimeter). I am converting the voltage to 3.3VDC because that's the voltage I need to drive the relay I am working with and also feed that voltage into one of the pins in the Raspberry Pi. Please note that the 24VAC source won't always be providing voltage but the rest of the system must still stay on.
The bottom part of the diagram shows my Raspberry Pi setup. I have an AC adapter that powers the Raspberry Pi with 5VDC through the mini USB port on the Raspberry Pi. I also have a Sainsmart relay that is connected to the Raspberry Pi through the 5VDC pin and the ground pin. Using a GPIO pin, I can control the relay by turning the GPIO pin to high or low (3.3VDC or 0VDC).
My project requires that the relay be controlled by the presence or absence of voltage from the 24VAC source. I am having a hard time finding a way to make that happen given that there are 2 wires coming out of the voltage converter and that I only have one control pin on the relay.
What do I need to do to make this work?
I am trying to figure out how to drive a relay with the output of a voltage converter. Please take a look at the diagram attached. The top part shows my current setup for converting the 24VAC voltage from the source I am working with (the boiler in my basement) to 3.3VDC. I'm using a voltage converter I found online and it's working perfectly (checked the output voltage with a multimeter). I am converting the voltage to 3.3VDC because that's the voltage I need to drive the relay I am working with and also feed that voltage into one of the pins in the Raspberry Pi. Please note that the 24VAC source won't always be providing voltage but the rest of the system must still stay on.
The bottom part of the diagram shows my Raspberry Pi setup. I have an AC adapter that powers the Raspberry Pi with 5VDC through the mini USB port on the Raspberry Pi. I also have a Sainsmart relay that is connected to the Raspberry Pi through the 5VDC pin and the ground pin. Using a GPIO pin, I can control the relay by turning the GPIO pin to high or low (3.3VDC or 0VDC).
My project requires that the relay be controlled by the presence or absence of voltage from the 24VAC source. I am having a hard time finding a way to make that happen given that there are 2 wires coming out of the voltage converter and that I only have one control pin on the relay.
What do I need to do to make this work?