Boeing 767 – Electrical - SmartCockpit - Airline training guides, Aviation, Operations, Safety

The BUS OFF light is illuminated. What does it mean?

Please select 2 correct answers

Static inverter has failed

Bus Tie Breaker is locked closed because switch is OFF or a Fault has occurred.

The Bus Tie Breaker is locked closed because switch is OFF (static inverter is closed)

The Bus Tie Breaker is locked open because switch is OFF or a Fault has occurred.

Correct! Wrong!

Pushing a Generator Control switch off opens both the field and generator breakers.

False.

True.

Correct! Wrong!

What can power a Utility Bus?

Respective Main AC, opposite Utility or AC Bus.

Respective Main AC or opposite Utility Bus only.

Respective Main AC Bus only

Correct! Wrong!

When is the Ground Service Bus powered?

Whenever the LEFT Main AC Bus is powered.

Whenever the EXT PWR AVAIL light is ON.

Whenever the RIGHT Main AC Bus is powered

Whenever the Ground Handling Bus is powered.

Correct! Wrong!

When APU GEN switch is positioned to OFF, APU GEN OFF light comes on. What condition might be indicated by the presence of both the ON flow bar and the APU GEN OFF light?

The APB is armed and will close when conditions are correct.

The APB is open as a result of a fault.

The APU GEN switch is positioned to OFF.

Correct! Wrong!

During a triple channel approach, the Right generator trips off at 140 feet RA. As a result, the F/O's primary flight instruments are lost.

True.

False.

Correct! Wrong!

The HDG produces power to:

Battery Bus and Hot Battery Bus, Left and Right AC Transfer busses, Captain's Instrument Transfer bus and Standby DC busses.

Battery Bus and Hot Battery Bus, Left and Right AC Transfer busses and Captain's Instrument Transfer bus.

Battery Bus and Hot Battery Bus, Left and Right AC Transfer busses, Captain's Instrument Transfer bus and Standby AC busses

Battery Bus and Hot Battery Bus, Left and Right AC Transfer busses, Captain's Instrument Transfer bus and Standby AC & DC busses

Correct! Wrong!

With the Bue Tie switch in AUTO, what causes the AC Bus ISLN light to illuminate ?

Bus fault has occured.

Open Bue Tie Breaker.

Closed Bue Tie Breaker.

Correct! Wrong!

Which of the following arms the load shed system to trip off both Utility Buses with the loss of a Generator?

Airplane in flight.

Both engine generator breakers closed.

Both engine Generator Drive lights extinguished.

Correct! Wrong!

A generator Drive light can indicate a high or low drive output RPM.

True

False

Correct! Wrong!

The Ground Handling Bus powers the battery chargers.

False.

True.

Correct! Wrong!

What bus powers the fire extinguishers?

Battery bus

Hot battery bus

Standby DC

Correct! Wrong!

When can the Ground Handling Bus be powered?

Only when the APU is running.

Only on the ground.

Either on the ground or in flight.

Correct! Wrong!

What does the STBY POWER OFF light indicate?

Only the Standby AC bus is unpowered

The STBY SELECTOR is positioned to OFF

Only the Standby DC Bus is unpowered

Either one or both Standby Buses are unpowered

Correct! Wrong!

What is required to enable the captain's flight instrument transfer bus to transfer with the loss of the Left Main AC?

Both Left and Right Bus tie switches must be in AUTO

Only the Right Bus tie switch must be in AUTO

Only the Left Bus tie switch must be in AUTO.

Correct! Wrong!

Three autopilots are armed for a triple channel approach. At 1200 ft RA, the Left generator is lost. As a result, the Left Main AC Bus is lost.

False.

True.

Correct! Wrong!

Which of the following inhibits the APU Generator Control OFF light?

Either engine generator breaker being closed.

Either a generator breaker or the external power contactor being closed.

External power contactor being closed.

Correct! Wrong!

What can power the Ground Handling Bus?

Only the APU.

APU, external power or an engine generator

Only external power or the APU

Correct! Wrong!

What is the normal source of power for the STANDBY AC Bus?

Main Battery.

Left DC Bus.

Left Main AC Bus.

Left Transfer Bus.

Correct! Wrong!

Which statement is true?

DC power normally comes from 2 Transformer Rectifiers Units (TRUs) which are powered by their respective MAIN AC busses. If AC power is not available to operate the TRUs, then either the HMG or the MAIN BAT provides DC power (APU battery only provides power for the APU)

DC power normally comes from 2 Transformer Rectifiers Units (TRUs) which are powered by their respective MAIN DC busses.

DC power normally comes from 2 Transformer Rectifiers Units (TRUs) which are powered by their respective MAIN AC busses.

AC and DC power normally comes from 2 Transformer Rectifiers Units (TRUs) which are powered by their respective MAIN AC busses. If AC power is not available to operate the TRUs, then either the HDG or the MAIN BAT provides DC power

Correct! Wrong!

Pushing the Generator Control switch off resets fault trip circuitry.

True.

False.

Correct! Wrong!

What is closed by pushing the Generator Control switch ON before engine start?

Generator breaker only.

Both the field and the Generator breaker

Generator field only.

Correct! Wrong!

The APU can be used to power the Left Main AC Bus while external power is powering the Right Main AC Bus.

True.

False.

Correct! Wrong!

Which has priority in supplying the ground handling bus, the APU or external power?

Whichever is manually selected.

APU.

External power.

Correct! Wrong!

The APU can be used to power the Left Main AC Bus while the Right engine generator is powering the Right Main AC Bus.

False.

True.

Correct! Wrong!

Prior to establishing electrical power, the Main Battery powers the Hot Battery Bus and after establishing electrical power, Main Battery Charger powers the Hot Battery Bus.

True.

False.

Correct! Wrong!

What bus powers most of the airplane fire detection systems?

Standby DC.

Battery bus.

Hot battery bus.

Correct! Wrong!

Which bus is powered automatically when external power is plugged in and available?

Standby AC.

Ground Handling Bus.

Ground Service Bus.

Correct! Wrong!

When the electric power fails, what happens to the cockpit door lock?

It remains in the position in which it was placed.

It unlocks automatically.

It can be opened from the cockpit, but not from the cabin.

Correct! Wrong!

In flight the Left engine is shut down. What electrical buses are lost?

Only the two Utility Buses

The Left DC Bus.

Only the respective Utility Bus

Correct! Wrong!

What is required to enable the F/O's instrument transfer bus to transfer with the loss of Right Main AC?

Only the Left Bus Tie switch must be in AUTO.

Both the Left and Right Bue Tie must be in AUTO

Only the Right Bus Tie switch must be in AUTO

Correct! Wrong!

What causes the Standby Power Bus OFF light to illuminate?

Battery charger failure

Loss of Left system power to standby buses

Loss of power on either the standby AC or DC bus

Correct! Wrong!

With the APU supplying both electrical and pneumatic power, what happens as the second engine is started?

Both Utility Buses trip off.

Only the Utility Bus for the engine being started trips off.

No utility bus trips off

Correct! Wrong!

When does the Utility Bus OFF light illuminate ?

Whenever the bus is unpowered

Only when the switch is OFF

Only when the switch is ON and the Bus is unpowered.

Correct! Wrong!

What is the highest automatic priority on the Left Main AC Bus?

External power.

Left engine driven generator.

APU generator.

Correct! Wrong!

Which of the following will cause the Generator DRIVE to illuminate?

High oil temperature.

High Generator load.

Clogged oil filter.

Correct! Wrong!

The standby buses can be powered from the Left Main AC and DC even with the Standby Selector OFF.

True.

False.

Correct! Wrong!

Pushing the Generator Control Switch off opens the generator field.

True.

False.

Correct! Wrong!

LEFT Main AC power is lost. What is the status of the STANDBY Buses?

Hot Battery Bus powers only STANDBY AC Bus, leaving STANDBY DC Bus unpowered

Right DC Bus powers Left DC Bus, STANDBY DC Bus & STANDBY AC Bus via static inverter

Hot Battery Bus powers from Standby buses

Hot Battery Bus powers only STANDBY DC Bus, leaving STANDBY AC Bus unpowered

Correct! Wrong!

What causes the Standby Power Bus OFF light to illuminate ?

Battery charger failure

Loss of power on either the Standby AC or DC Bus

Loss of Left system power to standby buses

Correct! Wrong!

With the APU supplying electrical power, what happens when the first engine is started?

The engine powers its respective buses only

Nothing happens until the APU is shut down

The engine powers both Main AC buses

Correct! Wrong!

What is the source order for powering Left and Right Main busses?

Respectice IDG then Oppposite IDG then APU Generator

Respectice IDG then APU Generator then Oppposite IDG

There is no source order.

Respectice IDG then Oppposite IDG

Correct! Wrong!

The OFF position of the Standby Power Selector de-energizes the battery bus, standby AC Bus and Standby DC Bus.

False.

True.

Correct! Wrong!

The Left Main AC Bus can power the battery switch off.

False.

True.

Correct! Wrong!

What buses can be powered by the HDG if the Main AC buses fail?

Only the Main AC Buses, both battery buses and both instrument transfer buses

Standby AC, Standby DC, both battery buses and both instrument transfer buses

Only the battery bus, hot battery bus and both instrument transfer buses

Only the two instrument transfer buses

Correct! Wrong!

Concerning 'Loadshedding' during engine start.

Utility and galleys trip with engine start selector to GND (both for No.1, affected for No.2)

Utility and galleys trip with engine start selector to GND (both for No.1 and No.2)

Utility and galleys trip with engine start for approximately 10 seconds (both for No.1, affected for No.2)

Correct! Wrong!

The Ground Service Bus powers the cargo doors and cargo handling equipment.

True.

False.

Correct! Wrong!

How many sources of AC power are there?

Six

Three

Four

Five

Correct! Wrong!

Two Engine Integrated Driven Generators (IDGs), one APU Generator, one Hydraulic Motor driven Generator (HMG) and one External power.

During a triple channel approach, the Left generator is lost at 140 ft RA. As a result the Left Main AC bus is lost.

True.

False.

Correct! Wrong!

The Ground Service Bus powers:

Two Battery chargers (MAIN + APU), the Equipment cooling fan, Left forward pump and the main entry door.

Three Battery Chargers, theEquipment cooling fan, Left forward pump and and the main entry door.

Two Battery chargers (MAIN + APU), the Equipment cooling fan, Left forward pump, Main entry door and the passengers lights.

Two Battery chargers (MAIN + APU), the Equipment cooling fan, and the Left forward pump.

Correct! Wrong!

Right DRIVE light comes on. EICAS advisory message appears. What is the cause of these indications?

Either the RIGHT Generator Drive oil pressure is too low or the oil temperature is too high

The RIGHT Generator Drive has been disconnected manually

The RIGHT Generator Drive has disconnected automatically

The RIGHT Generator Drive oil pressure is too low

Correct! Wrong!

What signals the HDG to operate?

If primary power is lost on both Left and Right AC Main Buses, the HDG operates automatically

Pilot action is required to activate the HDG

If primary power is lost on the Left AC Main bus, the HDG operates automatically

If all primary DC power is lost, the HDG operates automatically

Correct! Wrong!

Which statement is true of the Ground Service Bus?

Right DC Bus powers Left DC Bus, STANDBY DC Bus & STANDBY AC Bus via static inverter

Hot Battery Bus powers only STANDBY DC Bus, leaving STANDBY AC Bus unpowered

Hot Battery Bus powers from Standby buses

Hot Battery Bus powers only STANDBY AC Bus, leaving STANDBY DC Bus unpowered

Correct! Wrong!

When will the Utility Buses be shed during an engine start?

Only when the APU is supplying electrical and pneumatic power.

Anytime the APU is supplying electrical power

When the APU or external power is supplying electrical power

Correct! Wrong!

What can power the Ground Service Bus?

Only the APU or external power.

APU, external power or an engine generator.

Only the APU.

Correct! Wrong!

What does the generator Control OFF light indicate ?

Respective AC Bus not powered.

Generator Breaker open.

Bue Tie Breaker open.

Correct! Wrong!

You are preparing the flight deck for the first flight of the day. You have just positioned the BAT switch to ON. Why are the DRIVE lights ON?

High oil temperature in both drives

Low oil pressure in both drives - normal until drives are operational

Low oil pressure in both drives - do not start either engine

Both drives are disconnected.

Correct! Wrong!

The Bus tie system parallels engine generators but prevents any other sources from being paralleled.

True.

False.

Correct! Wrong!

During flight, if the Right engine Generator is lost and the Right Bus isolated on the EICAS. What will happen to the electrical system?

Right AC Bus will have no back-up power source

Right DC Bus will be unpowered

F/O's instrument Transfer Bus will be unpowered

Both APU and main Battery Chargers will remain powered

Correct! Wrong!

The HDG is operating while the gear is retracting.

False.

True.

Correct! Wrong!

What is accomplished by pushing the AC Bus Tie switches to AUTO?

Opens the Bue Tie Breakers.

Closes the Bus Tie Breakers.

Arms the automatic operation of the AC and DC Bue Tie system.

Correct! Wrong!

Airplane is in flight. Electrical system is in normal flight configuration. STBY POWER OFF light comes on. EICAS advisory message appears. Which position of the STBY POWER selector will provide an alternate power source to the standby buses?

OFF

BAT

AUTO

Correct! Wrong!

Pushing the Generator Control switch off causes the Generator Control OFF and Generator DRIVE lights illuminated.

False.

True.

Correct! Wrong!

Which of the following arms the load shed system to trip off Utility Buses when a generator is lost?

Both thrust levers in the takeoff range.

Both N2 RPMs at 50%

Both Bus Tie Breaker switches in AUTO.

Correct! Wrong!

A generator Drive light can indicate low oil pressure.

True

False

Correct! Wrong!

The OFF position of the Standby Power Selector de-energizes the battery bus, Standby AC bus and Standby DC bus.

True.

False.

Correct! Wrong!

DC power normally comes from two Transformer Rectifiers Units (TRUs) which are powered by their respective MAIN AC busses. If AC power is not available to operate the TRUs, then either the HMG or the MAIN BAT provides DC power (APU battery only provides power for the APU).

True.

False.

Correct! Wrong!

Where is the external power receptacle?

Forward of the nose wheel well.

Aft of the nose wheel well.

Under the Left wing.

Correct! Wrong!

To what bus is the Utility Bus connected, when the Utility Bus switch is ON?

Opposite Utility Bus.

External power.

Respective Main AC Bus.

Correct! Wrong!

Boeing 767 – Electrical