Yes the external earth strap is to take any current from a momentary short to +12v off the socket pin The basics of it all are in the pdf I referred to in an earlier post and I will be adding further info with pics when we do another one here The original Rotax single BMSC used on the BM's has a 1/4" spade connector for earth in the socket then an internal strap off the back of the spade connector which connects to the case. Makes life difficult to open up the ECU to replace components but protects the ECU. Those early ECU's survived some real torture when people first started trying to get into the firmware. I have some of them here
Screwing a piece of plastic to the + terminal is not a good idea and does not protect the BMSE from any other stray +12v leads. One ECU which was blown was the result of an owner wiring up accessories and it was the +12v accessory wire which shorted to the case, read the pdf I referred to in an earlier post
?? What's wrong with a small plastic cover over the battery positive post as a guard against my own stupidity, placing tools/ materials across the exposed posts while working on the bike? At least 90% of all vehicles out there have some sort of battery post isolation cover (at least for the + ), hard/soft plastic, I'm sure they can't have it all wrong. Doesn't stop me screwing up somewhere else in the system and fry the bugger, though... Btw...the screw/ small bolt used to hold the cover to the batt-post is non-conductive!!! Correct.
