No
built in battery backup, I should have written.
The point is, if all
four PFD and MFD power sources have failed, the power sources for the standby AI will also have failed. Ultimately, it is powered by both alternators and both batteries, so very redundant to begin with.
In a power related failure, you are less likely to lose both PFD and MFD than losing the standby AI.
If you want more detail, read on:
Distribution buses:- MAIN DIST 1 is powered by ALT1 and BAT1.
- MAIN DIST 2 is powered by ALT2, and automatically from MAIN DIST 1 (via a diode) if ALT2 fails (no cross-tie relay, so it only works one way, if you lose MAIN DIST 1 it is gone for good).
- ESS DIST is powered via diodes from MAIN DIST1, MAIN DIST 2, and BAT1.
- ESS DIST is also powered directly by BAT2 (through a slightly confusing path via the ESS1 bus)
Circuit breaker buses:- The standby AI is connected to ESS1, which is powered by ESS DIST and directly by BAT2
- It is also powered by MAIN1, which confusingly is powered by MAIN DIST 2
So overall, it gets power from all four power sources.