Electrical Panel Flashcards
TR UNIT light
- illuminates on ground if any TR has failed
- illuminates in flight if TR1 failed or TR2 and TR3 failed
ELEC light
- operates only on the ground if a fault exists in the DC or the standby power system
DC METER SELECTOR
• voltage (DC VOLTS) and load (DC AMPS) show on the alphanumeric display when you put the selector in the BAT position or any TR position
- BAT, TR1, TR2, and TR3
• STBY PWR = volts of the dc standby bus
- no amp indication since this is not a source of power
• BAT BUS = volts on the battery bus
- no amp indication since this is not a source of power
• BAT = volts and amps from respective battery charger or battery whichever is greater
- BAT position only
- amps vary with the state of the battery charge
- normal indication is zero, indicating a fully charged battery
• TR1 & TR2 = volts from DC bus 1 & 2 and amps from respective TR
• TR3 = volts and amps directly from TR3
AC METER SELECTOR
- the alphanumeric display shows these parameters for the 3 generators:
- voltage (AC VOLTS)
- load (AC AMPS)
- output frequency (CPS FREQ)
- the alphanumeric display shows only voltage and frequency when you select one of these:
- STBY PWR
- GRD PWR
- INV
BATTERY switch
OFF
ON
OFF
- removes power from the battery bus and switched hot battery bus when operating with normal power sources available (standby power switch in OFF or AUTO)
- removes power from the switched hot battery bus, battery bus, static inverter, AC standby bus, DC standby bus when battery(s) is the only power source
ON
- the battery or battery charger energizes these buses and components
- switched hot battery bus
- the Standby Power Control Unit (SPCU)
- provides automatic switching of the battery bus, DC standby bus, and AC standby bus (through the inverter) to battery power with loss of normal power
- the battery bus, DC standby bus, static inverter (SPCU closes the RCCB to give power to the inverter), and AC standby bus
- the LED alphanumeric display
- BAT bus can be powered with the BAT switch OFF by moving the standby power switch to BAT
CAB/UTIL Power Switch
ON
OFF
ON - supplies electrical power to the galley and cabin equipment systems - all 115V AC galley busses - left and right recirculation fans - fwd and aft door area heaters - drain mast heaters - lavatory water heaters - logo lights - potable water compressor - 115V AC shaver outlets if installed OFF - removes electrical power from these components
IFE/SEAT PASS Power Switch
ON
OFF
ON
- supplies electrical power to installed components of the passenger seats, in-flight entertainment systems, and other power systems
- 115v ac audio and video entertainment equipment
- cabin telephone equipment
- 28v dc video equipment and passenger seat electronic outlets
OFF
- removes electrical power from these components
BAT DISCHARGE light
- excessive battery discharge detected with BAT switch ON
- normal during APU start using ship’s battery
- does not illuminate if using AC power (#1 AC xfr bus is powered)