B737 AC/DC Metering Panel

AC/DC PNL
P5 FWD OVERHEAD

DC Ammeter

  • Indicates amperage of the source selected by the DC meters selector.

DC Voltmeter

  • Indicates voltage of the source selected by the DC meters selector.

AC Ammeter

  • Indicates amperage of the source selected by the AC meters selector.

Frequency Meter

  • Indicates frequency of the source selected by the AC meters selector.

AC Voltmeter

  • Indicates voltage of the source selected by the AC meters selector.

Battery Discharge (BAT DISCHARGE) Light

  • Illuminated (amber): With BAT switch ON, excessive battery discharge detected.

TR UNIT Light

  • Illuminated (amber):
    • On the ground: Any TR has failed.
    • In flight:
      • TR1 failed; or
      • TR2 and TR3 failed.

Electrical (ELEC) Light

  • Illuminated (amber): A fault exists in the DC power system or standby power system.
    • Note: Operates only with the airplane on the ground.

Maintenance Test (MAINT) Switch

  • Used by maintenance.

DC Meters Selector

  • Selects DC source for DC voltmeter and DC ammeter indications.
  • TEST: Used by maintenance.

Battery (BAT) Switch

  • OFF:
    • Removes power from battery bus and switched hot battery bus when operating with normal power sources available.
    • Removes power from battery bus, switched hot battery bus, DC standby bus, static inverter, and AC standby bus when the battery is the only power source.
  • ON (guarded position):
    • Provides power to switched hot battery bus.
    • Energizes relays to provide automatic switching of standby electrical system to battery power with the loss of normal power.

AC Meters Selector

  • Selects AC source for AC voltmeter, AC ammeter, and frequency meter indications.
  • TEST: Used by maintenance.

CAB/UTIL Switch

  • OFF: Removes electrical power from galley and cabin equipment systems including:
    • All 115V AC galley buses
    • Left & right recirculation fans
    • Forward and aft door area heaters
    • Drain mast heaters
    • Lavatory water heaters
    • Logo lights
    • Potable water compressor
    • 115V AC shaver outlets (when installed)
    • LED cabin lighting
  • ON: Supplies electrical power to galley and cabin equipment systems.

IFE/PASS SEAT Switch

  • OFF: Removes electrical power from installed components of the passenger seats, in-flight entertainment systems, and other power systems including:
    • 115V AC audio entertainment equipment
    • 115V AC video entertainment equipment
    • Cabin telephone equipment
    • FAX machine
    • 28V DC video equipment and passenger seat electronic outlets
    • 115V AC flight deck auxiliary power outlets
  • ON: Supplies electrical power to installed components of the passenger seats, in-flight entertainment systems, and other power systems.

Other Electrical Panels:
Ground Power and Bus Switching Panel
Generator Drive and Standby Power Panel