Electrical Exam Questions With All Correct Answers <Verified Answers> 2025 Marking Scheme New Update

Electrical Exam Questions With All Correct Answers &lt;Verified Answers&gt; 2025 Marking Scheme New Update The sources of AC power include: - Answer- 2 Integrated Drive Generators (IDGs) APU driven generator Ram Air Turbine (RAT) External AC Ground Power Unit (AC GPU) Once mechanically disconnected, an IDG cannot be reconnected in flight (true/false) - Answer- True The APU generator: - Answer- Can power the entire electrical system by itself Prior to engine start, based on these indications you know that: - Answer- The APU is powering the electrical system Prior to engine start, according to the ELECTRIC control panel: - Answer- AC external power is connected and is powering the electrical system In the event of a loss of AC power, the Ram Air Turbine (RAT) MUST be manually deployed using the RAT MANUAL DEPLOY handle. (true/false) - Answer- False Under normal operating conditions, DC power is provided by______Transformer Rectifier Units and_______ batteries. - Answer- 3/2 3 TRUs 2 batteries On battery power only, batteries will supply essential loads for how long? - Answer- 10 minutes Under what circumstances would we use a DC GPU? - Answer- For APU start if battery 2 is unavailable System logic provides electrical power for the aircraft according to the following source priority: - Answer- Respective IDG APU generator GPU Opposite IDG How many networks make up the electrical system on the airplane? Why? - Answer- 2 independent networks for segregation and fault isolation Which AC source has priority, the APU or GPU? - Answer- APU has priority and will automatically switch when the APU is up and running You receive the aircraft at the gate and it is powered by the AC GPU. You start the APU, once it is up and running, how can you tell that the APU generator has automatically taken over the electrical load? - Answer- AVAIL light on the GPU button, and MFD electrical page shows a green APU icon During "normal operation", will a failed IDG de-power the respective AC bus? - Answer- No How many Display Units (DUs) come to life when you bring the batteries online and which ones are they? - Answer- 2 DU 2 and 3 Can one IDG supply the entire electrical system? - Answer- Yes What are the two lights next to the IDGs? - Answer- Tells you which IDG must be disconnected and it's associated with an EICAS message When would the amber IDG oil indicator light illuminate? - Answer- High oil temperature, Low oil pressure and annunciator test button What action is taken when an amber IDG oil indicator light comes on? - Answer- Disconnect the associated IDG per the QRH If an IDG is mechanically disconnected can the flight crew reconnect it on the ground or in flight? - Answer- No What is the primary purpose of the IDGs - Answer- Supply AC power during all operations What is TRU? - Answer- Transformer Rectifier Unit What is the purpose of the Transformer Rectifier Units? - Answer- To convert AC to DC TRU transforms AC to DC, is there a way to change DC to AC? - Answer- Inverter What is the purpose of the inverter? - Answer- Converts DC to AC Can the APU fully replace a failed IDG? - Answer- Yes Does the APU generator have the same rating as the IDGs? - Answer- Yes At the gate, ground power is connected. What does it mean when the switch says AVAIL? - Answer- Voltage/Amperage/Frequency are within limits