[vettestr]

Dean,
I think I know the answers too these ?'s but why guess. What are you trying to do exactly, why are you installing this disconnect and do you care if it meets specific Race sanction rules?

A diode is an electronic device that is a 1 way valve, it only lets current flow in 1 direction. If you put it on the wire from the alternator it stops them funny electrons from swinging both ways. It stops current flow from feeding back and keeping our engine running on the alt. even though the battery was turned off. a 3 dollar item.

Some electronic fuel injections require a battery source to keep their memory stored or some info that the need remember fuel maps and so on. Most systems have ability to remember things without a battery but do need a battery supply to run.

Some sanctioning bodies require a mechanical switch and will not allow electronic or electric battery disconnect switches. (if you wrecked and an electrical fire was starting will the electric disconnect sw still work ?) A mechanical disconnect must be mounted in an exact location so track workers know where to look and how to turn everything off.

Will the Painless Sw. you listed work to stop battery flow .... YEP , but not sure about other questions I asked. Jeff C