Originally Posted by
EEngr
Not a 737 power system expert (more experience with 747 and 767), but wouldn't the Standby Power switch be placed in Auto (or Bat) as part of a normal startup sequence? There isn't an 'On' position to be precise. In Auto, the loss of all AC generators would result in Standby AC and DC loads being supplied by the battery (and inverter) automatically. For hopefully enough time to get the generators sorted out.
Not on the Classic. On the ground the AC and DC standby busses are not powered with the STANDBY POWER switch in AUTO to prevent battery discharge. The switch must be placed to BAT to power those busses.