Quote Originally Posted by attack eagle View Post
ok, the diode in the relay is 'flyback' protection. when you shut the power off to a relay the collapsing field sends a voltage spike back to the switch. the diode provides a path to ground for the induced spike, and helps reduce arcing (and carbon build up) at the switch itself.
it is NOT anything to be concerned with.
I understand most of that - I don't get "the diode in the relay" - what relay?