Today I finished off the plastic cover for the ammeter shunt. This is to prevent anything dropping onto the bare copper and shorting to the firewall. To mount the cover I simply fitted a couple nutplates direct to the firewall. No doubler plate needed as the cover is very light weight.
While in this area I also took some time to test the shunt wiring back to the EMS. Since I already have the VP-X which tells me the total electrical system load, I decided to place my ammeter shunt in series with the alternator supply cable. With these two known current draws, then the VP-X is able to work out the current flow to/from the battery. That is: Battery Amps = System Amps - Alternator Amps. If alternator amps is more than the electrical system, then the battery is charging. The bottom picture shows how this is represented on the EFIS.
In testing all this I did find that the EMS wires at the shunt were the wrong polarity. I swapped them over and all okay.
The plastic cover for my ammeter shunt is now fitted
Ammeter shunt wiring (to the EMS). At bottom is the Alternator supply fuse
