I've owned my Rupes 21 for about a year, one day it just turned off while mid panel. I took the handle off and inspected the electronics, everything looked fine. Cleaned the brushes and motor contacts. Put it all back together and it started working again. After 30-45 minutes it shut down again.

Took it apart again and started testing everything with a volt meter. I have power at the power cord, and at the switch. The voltage changes when the speed dial is moved, but the machine wont turn on. I swapped in a known good switch, still nothing.

At this point i think the electronic module has failed, but im trying to get some sort of tech support before spending $100 on a hunch.