Well... more like what shall I use for the timer. I have an extra relay output to run a pump on HERBUS for the seed tray. With Home Assistant it's trivial to tell it to run the pump for 0.5 seconds every 1/2 an hour. But then I have to pull it from the wall open the back, run some wires. way too much work.
I can use the AR4 software for the Aruino Leonardo and program the ROBOT sofware to run a loop that runs forever with a 30 minute delay and then relay on delay 0.5 seconds then off and back to step 1. But that ties up a PC etc.
I could program an Arduino to drive a relay and do the time loop.
Or use one of these and add the timing loop. About as much work as the Arduino. But it has 12V relay drivers that could run the motor directly. So less wiring.
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