This precision circuit can provide timings from 0.2 milliseconds to 3 minutes accurately. The circuit is from an 80's documentation.
In the figure we have a simple timer with the 555 feeding a relay directly. The circuit is from...
ON Semiconductor NTMJS1D5N04C 40V Industrial MOSFET Available from Mouser Electronics, these ON...
To control relays safely with double insulation, we suggest the circuit in the figure. The optical...