Snubbing diodes have been good engineering practice on inductive load circuits almost forever. When I bought this boat
, there was an indicator light for the propane
solenoid. Very quickly it didn’t work
. Aha! I’ll put in an LED, that will fix the problem. It lasted about two weeks. Being busy with other things, I just kept replacing it for a while. After much wasting of time and effort, I realized the back-EMF from the propane
solenoid was high enough to burn out the LED. Since the installation
of $.25 diode, the LED has lasted 21 years.