ELEC BACKUP GEN L, R
π Sources: QRH 6.2 (R53), FCOM 6.30.1
1. QRH Reference & Condition
- QRH Section: 6.2
- EICAS Level: Advisory
- Condition: The backup generator is failed.
2. Non-Normal Checklist
CAUTION
Attempt only one reset per flight.
| Step | Action |
|---|---|
| 1 | BACKUP GEN switch (affected side) β¦ β¦ Off, then ON |
- If message blanks: β β β β
- If message stays: backup generator remains failed
3. System Explanation
Each engine has a variable-speed, variable-frequency backup generator with a frequency converter. The backup system automatically powers transfer busses when: (FCOM 6.20.7)
- Only one main AC generator available
- Power to one or both main AC busses lost
- APP mode selected for autoland
Loss of a single backup generator is an advisory β the opposite backup generator can still provide backup power.
Loss of both backup generators (ELEC BACKUP SYS) is more significant as no backup AC power is available for transfer busses.
4. Cross-References
- Electrical System β Backup AC power description
- ELEC BACKUP SYS β Complete backup system failure
- ELEC AC BUS L, R β AC bus unpowered