# SDR DALA2020120103940

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 29, 2020
- Submitted: December 1, 2020
- Operation: Air carrier
- Aircraft: [N509DN](https://openairdocs.org/aircraft/N509DN), registered now
- Make and model: Airbus A350-941
- Registry model: [Airbus A350-941](https://openairdocs.org/model/airbus-a350-941) (OpenAirDocs)
- Aircraft serial: 0199
- Aircraft time: 11,948 hours, 1,080 cycles
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Power Supply
- Condition: Inoperative
- Location: Emergency Lights
- Stage of operation: IN
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DALA2020120103940

## Discrepancy

EPSU AT 4L (101WL4) INOPERABLE.  CORRECTIVE ACTION: R & R EPSU AT 4L (101WL4), PER A350 AMM 33-51.

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