Terms in this set (81)
What monitors the operation of the electrical system.
Flight Warning Computers (FWC)
How many onboard sources of AC power are available?
1. IDG 1
2. IDG 2
3. APU Generator
4. Emergency Generator
5. Static Inverter
Which generators are driven by a Constant Speed Drive (CSD)?
Engine driven Generators 1 and 2.
Also referred to as IDG 1 and IDG 2.
GEN + CSD = Integrated Drive Generator (IDG)
What is the rating of the three AC generators?
90 kVA, 115/200v, 3 phase, 400 Hz
What monitors the generator power output?
The respective Generator Control Unit (GCU)
When is it normal to see an amber FAULT light on the ENG GEN pb?
Prior to engine start
Is any single generator capable of supplying all essential AC power to the aircraft?
How are the IDGs lubricated and cooled?
Each has an independent oil system cooled by a fuel/oil heat exchanger using fuel from the associated engine's fuel system
Can an IDG be disconnected from its associated engine? If so, how?
Yes. By selecting the respective red guarded IDG pb.
Note: To avoid damage to the IDG disconnect mechanism, do not press an IDG pb for more than 3 seconds.
If an IDG is disconnected in flight, can it be reconnected?
No. Once disconnected, an IDG cannot be reconnected in flight.
What causes and IDG FAULT light?
High Oil Temperature or Low Oil Pressure
The pb returns to lights out when the parameters have been corrected or the IDG is disconnected.
Under normal conditions, where does the power from IDG 1 go?
AC Bus 1 and then to AC ESS and TR 1
Under normal conditions, where does the power from IDG 2 go?
AC Bus 2 and then TR 2
What does AC Bus 2 power, and what does it provide an alternate power source for?
TR 2 (DC Bus 2) and AC ESS bus (alternate)
What are the alternate power sources for the AC ESS bus?
AC Bus 2 and EMER GEN
Explain the purpose of the AC ESS FEED pb.
If AC Bus 1 fails or becomes unpowered, AC Bus 2 can be used to power AC ESS Bus by selecting the AC ESS FEED pb. If this occurs, ALTN appears in amber on the AC ESS FEED pb.
Note: This transfer may occur automatically on some aircraft.
How does the power switch when landing in the emergency electrical configuration?
After landing, when slowing below 100 knots, the RAT stalls and power reverts to battery only, causing the loss of the ND, MCDU, and SHED buses.
With the BUS TIE pb in AUTO, what is the normal AC Bus 1 and 2 power (generator) priority?
1. On side IDG
2. External Power
3. APU Generator
4. Off side IDG
(Onside, Outside, Inside, Offside)
With the BUS TIE pb in OFF, what is changed in the AC power priority?
The Bus Tie is deactivated and AC Bus 1 and 2 can only be powered by their respective (Onside) IDG.
External power and APU Gen cannot be connected
If the aircraft is at the gate with both engines shut down and APU running, the BUS TIE pb is OFF, and EXT PWR pb is ON, will the aircraft be powered?
No, with the BUS TIE pb OFF, APU Gen and external power cannot be connected.
If the engines are running and the APU is started, will the APU Generator automatically connect to the electrical system and disconnect the IDGs?
During the time it takes for the RAT to deploy, what is powering the AC ESS Bus?
The aircraft is on battery power only and the static inverter powers the AC ESS Bus
When the APU Generator comes online, will it automatically disconnect the external power?
Is the APU generator capable of powering the aircraft's entire electrical system?
Note: At higher altitudes the APU generator's load capacity is decreased due to generator inefficiency.
What does the EXT PWR pb AVAIL light indicate?
External power is connected and the Ground Power Control Unit (GPCU) has verified the voltage and frequency are within limits.
What will shed if the APU is the sole source of power in flight?
Main Galley buses
How is the emergency electrical configuration automatically activated?
Loss of AC Bus 1 and AC Bus 2
How is the EMER GEN powered?
The Ram Air Turbine (RAT) extends into the air stream and pressurizes the Blue hydraulic system fluid which powers the emergency generator.
Emergency configuration takes approximately how long to deploy the RAT, energize the blue hydraulic and power the emergency generator?
5 to 10 seconds.
What will happen if you press the RAT MAN ON pb with no power on the aircraft?
The RAT will deploy and could cause injury or death.
Is the APU start inhibited during emergency configuration?
Yes, for the first 45 seconds, to conserve battery power.
Should an APU start be attempted during emergency configuration? Why?
No. Because the batteries can not be charged using the emergency configuration (i.e. the BAT DIR Bus is not powered).
Can the batteries be charged during emergency electrical configuration?
No. The BAT DIR Bus is not powered during emergency electrical configuration.
The emergency generator is rated at ____.
5 kVA, 115/200v, 3 phase, 400 Hz
What is the difference between manually deploying the RAT on the hydraulic panel vs. the electric panel?
If the RAT is deployed by the RAT MAN ON guarded switch on the Hydraulic Panel the Emergency Generator will not come online.
Which buses will the emergency generator power?
AC ESS bus and DC ESS bus
Which screens will be powered in the emergency electrical configuration? Battery power only?
Emer electrical configuration: left PFD, ND, MCDU 1 and E/WD
Battery power only: Left PFD and E/WD
What does a FAULT light on the AC ESS FEED pb indicate?
The AC ESS Bus is unpowered
What does a ALTN light on the AC ESS FEED pb indicate?
AC Bus 2 is powering the AC ESS bus (pb pushed)
Some aircraft have a mod to allow AC Bus 2 to automatically power the AC ESS bus if AC Bus 1 fails or becomes unpowered. In this case the ALTN pb will not illuminate.
How can the AC Ground/Flight Service Bus be powered?
AC Bus 2 or External Power
What is the priority to power the AC ESS Bus?
1. Emergency generator
2. AC Bus 1 or 2
3. Aircraft batteries (through the static inverter)
The static inverter is rated at _____.
1 kVA, 115v, single phase, 400 Hz
What is the purpose of the static inverter?
When the aircraft is on battery power only, the static inverter will power the AC ESS bus.
What will cause the RAT & EMER GEN red FAULT light to illuminate?
Emergency generator is not providing power to the AC and DC ESS buses when power to AC BUS 1 and 2 is lost.
When should the red FAULT light on the RAT & EMER GEN light be expected?
During the 5 - 10 second RAT deployment and power up. The aircraft is on battery power only.
The memo "EMER GEN" appears in _______ when the Emergency Generator is running.
Green on the ECAM memos
How many Transformer Rectifiers (TRs) are installed in the electrical system and how are they normally powered?
1. TR 1 - AC Bus 1
2. TR 2 - AC Bus 2
3. ESS TR - Not normally powered
What is the max continuous load for each TR?
What is normally powered by TR 1?
DC Bus 1 ---> DC BATT ---> DC ESS
What is normally powered by TR 2?
DC Bus 2
What is normally powered by ESS TR?
Nothing. ESS TR is a backup power source for DC ESS Bus
What can power the ESS TR?
Either the AC ESS Bus or the Emergency Generator depending on the malfunction
DC Bus 2 is a backup power source for what two buses?
DC Bus 1 and DC BAT Bus
What bus normally powers DC ESS bus?
DC BAT bus
What is indicated by an amber SHED on the ECAM Electrical page?
Either the AC ESS Shed or DC ESS Shed bus has failed or is unpowered. These buses are not normally displayed.
What happens automatically in the DC system with the failure of an AC Bus or TR?
After approximately 5 seconds, the DC system will automatically power the unpowered DC Bus from the opposite DC Bus through the DC BAT Bus
When one TR is powering both DC Buses, how is the DC ESS Bus powered?
DC ESS bus is automatically powered by the ESS TR.
If both TRs fail, which DC Bus is still powered?
The ESS DC Bus will be powered by the ESS TR
The aircraft is equipped with how many NICAD batteries?
Both are located in individual vented compartments located within the avionics compartment.
Battery power is primarily used for what two purposes?
1. APU starts
2. Backup power to the AC and DC ESS buses.
What is the minimum battery voltage?
What happens when the BAT 1/2 pbs are selected on (lights out)?
The respective Battery Charge Limiter (BCL) enables the battery to automatically:
1. Connect to the DC BAT BUS (for charging and discharging)
2. Charge (when required)
3. Sense and report faults
4. Power the AC ESS and DC ESS buses when in the emergency electrical configuration until the emergency generator becomes available
How long does it take to charge the batteries?
Up to 20 minutes
During the flight deck preflight, what are you looking for during the Battery check?
1. Select ECAM Electrical System page
2. Select BAT 1 & 2 OFF and then ON
3. Verify Battery charge current is < 60 amps and decreasing within 10 seconds.
What is indicated by a FAULT on the BAT pb?
Battery charging current out limits, battery contactor has opened.
With a battery or BCL fault, what happens automatically?
The battery is automatically isolated from the electrical system
FAULT appears on the BAT pb
Will the batteries ever completely drain if left on on ground?
No, the BCL will disconnect the battery when it reaches a low voltage.
What is the normal capacity of each battery?
How can you determine if a battery is being charged?
On the ECAM Electrical System page the directional current arrows will be pointing towards the battery.
In flight when the batteries are the only source of electrical power, what will the batteries power?
Battery 1 powers AC ESS Bus through the static inverter
Battery 2 powers DC ESS Bus
In flight effective continuous battery usage is limited to approximately how many minutes?
Where are the circuit breakers for components powered by the emergency electrical configuration?
What does a green circuit breaker indicate?
A green circuit breaker is monitored by the FWC. An ECAM message will be displayed after a green circuit breaker has been tripped for one minute.
What does a black circuit breaker indicate?
A black circuit breaker is not monitored by the FWC. However, the associated system is monitored by the ECAM.
What does a red collared circuit breaker indicate?
The red collar prevents the flight crew from resetting these circuit breakers. Wing Tip Breaks are never to be reset in flight.
Explain the logic of the GALLEY pb
When the GALLEY pb is OFF -
Both the Main and Secondary galley buses are shed.
When the GALLEY pb is in AUTO -
1. On the ground, with APU or External Power, both the Main and Secondary galley buses are powered. With only one IDG, the Main galley bus is shed.
2. In flight with only one generator, the Main galley bus is shed. However, the secondary galley bus remains powered.
What is indicated by a FAULT light in the GALLEY pb?
At least 1 generator is above its rated output
What is the EMER GEN TEST pb on the EMER ELEC PWR panel?
It is a maintenance push button to test the emergency generator using the blue hydraulic engine driven pump.
What does the SMOKE light indicate in the GEN 1 LINE pb?
Smoke is detected in the avionics ventilation ducting
What happens when you push the GEN 1 LINE pb to OFF?
1. The IDG1 line contactor opens and the white OFF light illuminates.
2. AC Bus 1 is powered by AC Bus 2 through the BUS TIE
3. GeN 1 is isolated from the electrical system and only powers 1 fuel pump in each wing tank.
When landing in the emergency electrical configuration, what buses are powered?
319 - The emergency generator provides power until touchdown and deceleration through 100 knots. The RAT stalls at 100 knots and the aircraft reverts to battery power only.
320 - When the landing here is extended, the aircraft reverts to battery power only. If a go-around is necessary, the emergency generator will need to be reset when the gear is retracted by pressing the MAN ON pb.