Following protoflight component testing of a Solar Array Drive Assembly (SADA), post-test electrical measurements revealed shorted circuits caused by slip ring brush displacement. Initial investigation, disassembly and analysis suggested the root case was related to insufficient preload in an axial bias spring constraining the slip ring rotor. Successful rework and re-test supported this conclusion. However, later tests of similar hardware for a subsequent program resulted in a comparable electrical anomaly. Original investigation results were reviewed and found to still be valid. However, additional contributing factors were identified that led to the reoccurrence of the anomaly. This paper explores the discovery, investigation, analytical approach, and ultimate resolution of a SADA slip ring anomaly.
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