Dc Electrics

Front 1

What do the amber arrows mean?

Back 1

The batteries are discharging

Front 2

The DC generators...

Back 2

... Are not connected as long as GPU is ON (EXT PWR priority)

Front 3

In flight DC generator one fails...

Back 3

... You expect the BTC to close automatically

Front 4

In flight...

Back 4

... DC bus 2 has failed

Front 5

In case of a dual DC generator loss...

Back 5

... An automatic switching allows the batteries to supply some DC buses

Front 6

With the engines shutdown and the BAT switch off...

Back 6

... The batteries remain connected to their respective HOT BAT busses

Front 7

What is the function of the EMER BAT while the ENG START rotary selector is set to START or CRANK?

Back 7

It provides positive power to protect critical items from power transient.

It never powers the starters.

Front 8

Once the starter generator has started the engine, it switches to the generator mode when the engine speed accelerates past:

Back 8

NH 61.5%

Front 9

Aircraft on ground, engines running, DC EXT power available and selected ON:

Back 9

DC EXT PWR has priority over ENG DC GEN

Front 10

Assuming normal operation in flight, when are the DC EMER and DC ESS buses connected to DC bus 1 and/or DC bus 2?

Back 10

Always through the BAT CHG connectors and respective HOT EMER or HOT MAIN BAT bus

Front 11

In flight with OEI, which indication would be displayed on the shutdown engines DC GEN pushbutton?

Back 11

Amber FAULT of push button is depressed (in)

Front 12

With all four aircraft generator push buttons in, and EXT PWR supplying both ACW and DC, which light should be illuminated in all four generator pushbuttons?

Back 12

Amber FAULT

Front 13

The UND/V light illuminates amber when:

Back 13

DC STBY bus voltage is less than 19.5 volts

Front 14

With the engines shut down and the BAT switch on:

Back 14

Allows EXT PWR operation, or a reduced DC supply

Front 15

When the DC starter/generator is functioning as a starter during a battery start:

Back 15

It is electrically supplied from the HOT MAIN BAT bus

Front 16

Assuming normal operation in flight, how is the constant frequency AC power obtained?

Back 16

From the DC buses through two inverters

Front 17

In the event of thermal runaway of the MAIN BAT and the MAIN BAT CHG FAULT light illuminates (BAT CHG contactor opens) and:

Back 17

The MAIN BAT supplies the HOT MAIN BAT bus and DC ESS bus is transferred to DC bus 1

Front 18

Illumination of one emergency power indicator (arrow) in flight shows:

Back 18

The supply of DC ESS or DC EMER bus from the corresponding HOT BAT bus

Front 19

What is the function of the OVRD position for the BAT toggle switch?

Back 19

Overrides all automatic operation to ensure that the buses are supplied by their respective battery

Front 20

With the STBY bus OVRD push button set to OVRD, where will the DC STBY bus and AC STBY bus (via INV 1) be supplied from?

Back 20

The HOT EMER BAT bus

Front 21

From where is the DC GND HLDG bus powered?

Back 21

HOT MAIN BAT bus or DC SVCE bus

Front 22

With the aircraft on the ground, BAT switch is Off and the EXT PWR AVAIL light illuminated, what must be done to fully power the DC electrical system?

Back 22

Place the BAT switch to ON and after the self test process is complete press the EXT PWR push button

Front 23

Following an inverter failure the INV light illuminates and:

Back 23

The associated AC bus is supplied by the other inverter.

Front 24

In the event that both DC bus 1 and DC bus 2 are lost INV 1 will be supplied automatically by the HOT MAIN BAT bus or:

Back 24

By the HOT EMER BAT bus in the OVRD configuration, or the TRU if selected on

Front 25

With the DC BTC pb selected to NORM, when will the flow bar illuminate?

Back 25

Only during EXT PWR, Hotel mode or single generator operation

Front 26

With batteries only, when will both AC bus 1 and AC bus 2 be supplied?

Back 26

Never

Front 27

If the number one inverter fails:

Back 27

The AC bus 1 BUS OFF light will illuminate for 10 seconds, and then extinguish and INV FAULT light illuminates

Front 28

During the start sequence on the ground, the cross start system:

Back 28

Uses the MAIN BAT and opposite DC GEN

Front 29

The EMER BAT CHG light will illuminate when:

Back 29

-battery overheat occurs (automatic disconnection)

-no battery charge when required

Front 30

With batteries only, AC bus 1 and 2 are:

Back 30

Never supplied

Front 31

With only the BAT switch ON, which battery powers the DC STBY bus?

Back 31

The main battery