LsFarm wrote: just put a simple toggle switch on the auger, and let it work while you empty the ash pans.
If I might add a twinge of wisdom from my own experiences -- you might want some kind of failsafe timer to switch off the auger after a predetermined time, just in case you forget to manually flip the toggle after emptying the ashes.
I had a switch to turn off the blowers while I emptied the ashes. On two occasions I got distracted by something
(kids, phone, dog, life, who knows...I can't remember) and I forgot to switch the blowers back on and the fire went out.
Now my setup stops the blowers for 3 minutes, or until I press the "resume" button, whichever comes first.