Hi,
I am doing an irrigation project and want to send MQTT messages to one ESP32 with two different relays and solenoid valves to start water irrigation. I do not trust one message to turn on and another to turn it off after x minutes since if the ESP32 misses the off message the valve are going to poor water forever. Instead I would like to control the amount of time the valves are open by sending a MQTT message including time e.g. 10 minutes and start a timer on the ESP32.
Simply one message that says, turn on Valve1 for 10 minutes and another that says turn on Valve2 for 15 minutes.
Everything is controlled with a Node red Raspberry.
Thanks for all kind of help I can get on this.