Finally got a simple ESP8266 powered gate opened up and working. The pins are controlled via MQTT messaging and tested with 3 simple LED's with 30N06L MOSFET's. So when the incoming MQTT message comes in, it sets the appropriate pin HIGH which is to GATE on the FET.
That's fine, then I realized that the garage door opener keypad is normally sending 5V on the OPEN, CLOSE, AND STOP buttons. So my N-FET model doesn't work as it's normally open and I send voltage on GATE to close it.
If I have a 5V normally OPEN connection that I need to close for about 1-2 seconds a few times a week, is there a normally open FET, Relay, SSR? I 've seen a JFET not sure if it's appropriate here.
I'm using a wall socket to power the ESP8266 so 3.3V is all I have to work with.
- If I looked at a normally open relay, could I use a 3.3V to 5V logic converter to power the relay and set the PIN low when I trigger it?
- Is there another FET that I can use the 3.3V that I have to trigger a OPEN of the circuit that is NC.
- Is there another way that I can use my existing 30N06L to convert it from NO to NC?
I was so happy to see the lights shine when I pressed the button on my phone to MQTT then a bit of a facepalm when I realized the electrical part of my project was flawed.