Electrical

Question 1

How many NiCad batteries are there on the aircraft?

Answer 1

3

MAIN, AUX, STBY

Question 2

How many engine-driven DC starter-generators are there on the aircraft?

Answer 2

2 (1 each engine)

Question 3

How many Transformer Rectifier Units (TRUs) are there on the aircraft?

Answer 3

2

Question 4

How many APU generators are there on the aircraft?

Answer 4

1

Question 5

T/F: The electrical system comprises both a direct current (DC) system and an alternating current (AC) system

Answer 5

TRUE (28VDC and 115VAC)

Question 6

T/F: DC power to the electrical system is supplied by two engine-driven DC generators only.

Answer 6

FALSE, 3 batteries, 2 TRUs, the APU Generator, and External Power can be used

Question 7

T/F: Circuit breaker panels can be found in the left and right main landing gear wheel wells.

Answer 7

TRUE (in the AC Contactor boxes)

Question 8

How many circuit breaker panels are there in the flight compartment?

Answer 8

4

Question 9

Which of the following are NOT electrical buses?

answer with which of the following ARE electrical buses?

Answer 9

L & R Main Bus
L & R Secondary Bus
L & R Essential Bus
L & R AC Bus
Battery Bus
(Note: emergency bus is NOT a bus)

Question 10

The aircraft is equipped with which of the following batteries?

Answer 10

Main
Auxiliary
Standby

Question 11

Which batteries are used for engine starting when ground power is not available?

Answer 11

Only MAIN and AUX batteries

Question 12

How long will the batteries power the aircraft if normal electrical power fails?

Answer 12

up to 60 minutes

Question 13

How many battery switches are there?

Answer 13

4 switches on DC control panel (Battery Master, MAIN BATT, AUX BATT, and STBY BATT)

Question 14

T/F: If the battery master is in the OFF position, the other batteries can still be used to power the aircraft?

Answer 14

FALSE

Question 15

T/F: When the battery master is in the OFF position, all battery power is turned off no matter what position the other switches are in.

Answer 15

TRUE

Question 16

If the battery is being charged at a 100% rate of charge, how will it be depicted on the MFD Battery page?

Answer 16

1.00 because that is 100% normal charge rate

Question 17

How is a battery that is discharging displayed on the MFD Electrical page?

Answer 17

It will have a “-“ sign and a percent discharge (ie. -.30 = 30% over maximum rate of discharge)

Question 18

When the battery temperature is within limits, what color does it display as on the MFD Electrical page?

Answer 18

White

Question 19

When the battery temperature exceeds normal limits, what colors would display on the MFD Electrical page?

Answer 19

Amber
or
Red

Question 20

If any battery temperature is 50 degrees C to 65 degrees C, what color does the battery temperature display as on the MFD Battery page?

Answer 20

Amber

Question 21

Where can the GPU be connected to the aircraft for DC power?

Answer 21

Left forward fuselage

Question 22

When connected to external power on the ground, DC EXT PWR ON is displayed in what color?

Answer 22

Green when connected

Question 23

T/F: The EPCU protects the system from too high and too low DC power voltage from the DC external power source.

Answer 23

TRUE

Question 24

After engine start, how many volts does the DC generator provide?

Answer 24

28VDC

Question 25

Where are the Transformer Rectifier Units (TRUs) located?

Answer 25

Nose of aircraft

Question 26

TRUs change 3-phase 115VAC to what?

Answer 26

28VDC

Question 27

During normal operation, which busses do the TRUs power?

Answer 27

L or R Secondary ("Feeder") buses

Question 28

A L TRU caution light will illuminate when what happens?

Answer 28

TRU is offline or fails

Question 29

On the ground, what busses does the APU generator provide power for?

Answer 29

L & R Main bus L & R Secondary Bus L & R Essential Bus

Question 30

What does it mean when a plus sign (+) is displayed in front of a value on the MFD Electrical page?

Answer 30

Indicates an overload of the power source

Question 31

The entire DC electrical system can still be powered when up to how many power sources have failed?

Answer 31

2 power sources

Question 32

When does the EPCU send a signal to the generator to trip it offline during a Main DC bus fault?

Answer 32

If the fault persists for 5 seconds or more

Question 33

If the Right Main Bus has a bus fault, which battery is disconnected from the system?

Answer 33

The Main Battery

Question 34

T/F: If a Secondary bus fault occurs, the increased current will trip the circuit breaker for the respective TRU.

Answer 34

TRUE

Question 35

In addition to an inoperative TRU, what is required for the EPCU to enter emergency mode?

Answer 35

Airplane in air | Both DC generators unavailable

Question 36

In addition to a dual DC Generator failure, what is required for the EPCU to enter emergency mode?

Answer 36

Airplane in air | At least 1 TRU unavailable

Question 37

T/F: In EPCU emergency mode, the batteries are the main source of power.

Answer 37

TRUE

Question 38

When in EPCU emergency mode, which busses automatically disconnect from the batteries?

Answer 38

Main busses

Question 39

What is the voltage output of the AC generators?

Answer 39

115VAC 3-phase

Question 40

Where are the AC generators mounted on the aircraft?

Answer 40

On each engine's propeller reduction gearbox

Question 41

How many external AC power ports are there on the aircraft?

Answer 41

1 AC power port (on inboard side of right engine nacelle)

Question 42

When the aircraft is powered by external DC power, which busses are powered?

Answer 42

L & R Main L & R Secondary L & R Essential

Question 43

T/F: When a DC generator fails, the Main Bus Tie switch must be manually selected to keep the associated Main DC bus powered.

Answer 43

FALSE, EPCU can change the status of the bus tie automatically

Question 44

Which switch would pilots use to connect the main battery to its associated Main feeder bus?

Answer 44

The MAIN BATT switch

Question 45

T/F: The electrical system has a single hot battery bus to keep certain items powered at all times.

Answer 45

TRUE

Question 46

T/F: The hot battery bus can be powered by any of the 3 batteries.

Answer 46

FALSE, standby battery only

Question 47

At what point will DC electrical bus load shedding begin?

Answer 47

3 (or more) DC source failures

Question 48

In EPCU Emergency mode, the _____ are the main power source for the available DC busses.

Answer 48

Batteries

Question 49

The AC generators connect to the system when the engines are running, GEN 1 and 2 switches are selected ON, and _____.

Answer 49

condition levers are in MIN to MAX range