use the schedule program in the Ewilink app for timing on -off.
I also have the same need. I would like to turn on a circulation pump but it should be off automatically after 10 minutes
This seems to be the "inching" function, currently present in Sonoff Basic to be ported to the POW...
I I read it correctly did I make the same mistake to use loop timer. This turns off the light every 10 minutes. So when you enable it 1 mine before the timer it is only on for 1 min. Took me really long to figure this out... If you go to settings of the device you can set inching. With this you can turn off the device after a certain time.