How does NBPT work on the A350?
- The DC1 and DC2 busbars are automatically connected to their respective batteries therefore alleviating any breaks in power transfer.
- Only on DC system
- Available in flight and on ground
What does the APU do in the event of all generators fail?
- APU is available for start
- Supplies only side 1 (AC1A and AC1B)
Above what speed can the RAT supply power?
Above 140kts
- When would the ISOL 1&2 pb be pressed?
- What does it do?
- During the SMOKE QRH procedure
- It isolates side 1 and 2 of the electrical network
Where is the RAT located?
On the right hand side of the aft belly fairing
What does the OPU do?
- Overvoltage Protection Unit
- Backup to the Generator Control Unit (GCU)
- Prevents overvoltage situations on the busbars
What does the APU do in the event of a dual engine failure?
- Automatically starts
- Supplies only side 1 (AC1A and AC1B)
What backup is there to the generators and the batteries?
- EMER PWR through the RAT
- APU GEN
How much voltage do the EXT PWR units provide?
- 115V AC
What happens when all engine generators and the APU generator are failed?
RAT supplies emergency network
How many batteries does the A350 have?
What are they?
How much voltage do the batteries supply?
- 4
- BAT 1, BAT EMER 1, BAT EMER 2, BAT 2
- 28V DC
What is an ATU?
What does it do?
- Automatic Transformer Unit
- Transforms 230V AC into 115V AC and vice versa
What does EPCU stand for?
What does it do?
- External Power Control Unit
- Controls frequency and voltage
- Limits power to 90kVA
- Detects overloads
When does load shedding occur on the A350?
If there is a failure of three or more generators
- When would the BUS TIE pb be pressed?
- What does it do?
- During EMER CONFIG
- It separates the busbars from each other
What battery charge are you looking for during the battery check on the following aircraft?
A330
A359
A351
- 5 V
- 1 V
- 0 V
How many generators does the A350 electrical system have?
How much voltage do they supply?
- 4
- GEN1A, GEN1B, GEN2B, GEN2A
- 230V AC
When is the load on a generator considered normal?
And the voltage?
- When the load is below 120%.
- Between 230-240V
How many generators can the APU GEN replace on ground and in flight?
- Entire network on ground
- 2 ENG GEN in flight
