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STANDBY POWER Switch:. .AUTO (Guarded position)-- During NORMAL operations:. .A) #1 Transfer Bus powers the AC Standby Bus. .B) #1 DC Bus powers the DC Standby Bus. . . .- Loss of either normal source (A or B above) in-flight:
A) Static Inverter powers the AC Standby Bus (through the Battery Bus). .B) Battery Bus powers the DC Standby Bus
-- Loss of all AC power on the ground there is NO automatic transfer of power.
OFF -- Standby Buses are NOT powered; . .STANDBY PWR OFF light is illuminated
NOTE: The Static Inverter is NOT powered; and The Standby Attitude Indicator (SAI) is NOT powered.
BAT -- . .A) Hot Battery Bus powers the Battery Bus. .1) Battery Bus powers the DC Standby Bus. .2) Battery Bus powers the Static Inverter. . a) Static Inverter powers the AC Standby Bus
NOTE: In BAT position, the Hot Battery Bus powers the Battery Bus regardless of this Switch's position.
NOTE: Battery can supply power to the Standby Equipment for about 30 minutes.