B777 Electrical

Boeing 777 Electrics

Boeing 777 Electrics

1 / 15

What is the correct electrical panel configuration for normal flight?

BUS TIE switches in AUTO, BATTERY switch OFF, GENERATOR CONTROL switches ON.

BUS TIE switches in AUTO, BATTERY switch ON, GENERATOR CONTROL switches ON.

BUS TIE switches in ISLN, BATTERY switch ON, GENERATOR CONTROL switches ON

BUS TIE switches in AUTO, BATTERY switch ON, GENERATOR CONTROL switches OFF.

2 / 15

During autoland, the busses isolate to allow three independent sources to power the three autopilots.

True.

False.

The left IDG powers the left AC transfer bus, the left main DC bus, and the captain’s flight instrument bus The right IDG powers the battery bus and AC standby bus through the main battery charger The backup system powers the right AC transfer bus, the right DC bus, and the first officer’s flight instrument bus.

3 / 15

On ground no power connected to the airplane. Which items will be powered if you push the BATTERY switch ON?

The hot battery bus will be powered.

Only the main battery bus will be powered.

All statements are correct.

The APU controller and the DC fuel pump will be powered.

4 / 15

The main battery provides standby power to the following:

The hot battery bus, the captain’s flight instrument bus, and the standby inverter.

The hot battery bus, the battery bus, the captain’s flight instrument bus and the standby inverter.

The hot battery bus, the battery bus and the captain’s flight instrument bus.

The hot battery bus, the battery bus, the captain’s flight instrument bus, the left and center flight control PSAs, and the standby inverter.

5 / 15

How many main AC power sources are required to maintain the entire plane AC electrical load?

4

2

5

1

6 / 15

Which of the following is not a main AC electrical power source?

Primary and secondary external power.

APU generator.

Left and right engine integrated drive generators (IDGs).

Transformer Rectifier Units (TRUs).

7 / 15

Bus tie relays, controlled by BUS TIE switches, isolate or parallel the right and left main busses. When both BUS TIE switches are set to AUTO, the bus tie system operates automatically to maintain power to both main busses.

True.

False.

8 / 15

What is the correct source order for powering left and right main busses in flight?

APU generator - respective IDG - opposite IDG.

Opposite IDG - APU generator - respective IDG.

Respective backup generator - APU generator - opposite backup generator.

Respective IDG - APU generator - opposite IDG.

9 / 15

What provides DC power on the B777?

Transformer rectifier units.

Standby inverters.

DC generators.

Transfer busses.

10 / 15

Which one of the following is not true about the Primary External Power?

When the Primary power source voltage and frequency are within limits, the primary external power AVAIL (available) light illuminates.

If the APU generator is running, pushing the PRIMARY EXTERNAL POWER switch ON connects primary external power to the right main bus, leaving the previous source connected to the left main bus.

If a single IDG powers both busses, pushing the PRIMARY EXTERNAL POWER switch ON connects primary external power to both busses and removes the IDG source.

If both busses are powered from secondary external power, pushing the PRIMARY EXTERNAL POWER switch ON connects primary external power to the both main busses.

11 / 15

Which one of the following is not true about the standby inverter?

The standby inverter powers the AC standby bus if the left transfer bus is not powered.

The standby inverter is powered from the ram air turbine (RAT) generator.

The standby inverter converts DC power to AC power.

The standby inverter is powered from the battery bus.

12 / 15

How many total AC sources of power does the B777 accommodate?

7

5

6

4

Seven (2 IDG, APU, PRI and SEC external power, 2 BUG).

13 / 15

Which bus powers the main battery charger and the APU battery charger?

Standby bus.

Right main bus.

Ground service bus.

Left main bus.

14 / 15

The Electrical Load Management System (ELMS), manages load shed priority (galley first, utility bus second, then selected AC components).

True.

False.

15 / 15

Which one of the following is not true about integrated drive generators (IDGs)?

The IDG can be electrically disconnected from the busses by pushing the GENERATOR CONTROL switch to OFF.

The DRIVE light illuminates and the EICAS message ELEC GEN DRIVE L or R displays when low oil pressure is detected in an IDG.

The IDG drive can be disconnected from the engine by pushing the respective DRIVE DISCONNECT switch.

The IDG can be reconnected by the flight crew by pushing the respective DRIVE DISCONNECT switch.

Your score is

By Wordpress Quiz plugin

Get These Blog Posts Straight To Your Email!

Never miss a blog post again. Get all the information directly to your email inbox!