Replace the large-current slip ring brushes
Replace the large-current slip ring (LCSR) brushes — brush-only or the full brush assembly — once wear reaches the 2 mm abrasion-limit line, working with all gantry breakers OFF and the dedicated alignment jig to seat the new brush true to the ring.
Tools & parts
| Item | Part number | Qty |
|---|---|---|
| Standard tools | n/a in source | 1 set |
| Low-voltage slipring brush (only)* | 4X79-05042 | Required number not stated in source |
| Low-voltage slipring brush assembly* | BX77-3487-1 | Required number not stated in source |
| Rag | n/a in source | 1 |
| Scale (150 mm) | n/a in source | 1 |
| Vacuum cleaner | n/a in source | qty not stated in source |
| Cutter | n/a in source | qty not stated in source |
| Torque wrench (M6) | rated for 4.4 N·m — no part number in source | 1 |
| Needlenose pliers | n/a in source | 1 |
| Brush alignment jig | BSX77-4283 | 1 |
Safety
Hazard: High voltage present in the slip ring and the brushes
Consequence: Electric shock
Avoidance: Turn OFF all the breakers on the distribution board before touching the slip ring or the brushes
Hazard: Abraded slip-ring brush material (the brushes contain metal elements) generated while replacing worn brushes; source labels this call-out "NOTE" — reclassified CAUTION here as a personal-health precaution, not an equipment-only one
Consequence: Inhaling airborne abraded brush material
Avoidance: Thoroughly ventilate the work area and take protective measures such as wearing a protective mask before starting work
Hazard: Mishandling the ring, its cover, and the fragile brushes while replacing them; source labels this call-out "CAUTION" — reclassified NOTICE here because all five listed outcomes are equipment/procedure-quality issues, not personal injury
Consequence: Force applied while removing the cover can damage the ring; the brushes are fragile and can break if mishandled; abraded material (powder) can fall into the gantry; brush assemblies can end up mounted off-center; or the cable can be left incorrectly connected
Avoidance: When removing the cover, apply no force to the ring; handle the brushes carefully and remove only their burrs, using a cutter; keep abraded material (powder) from falling into the gantry; when mounting the brush assemblies, position them at the center of the ring; verify the cable is connected correctly
Hazard: Handling the brush while inserting it into the sliding section (step 10); source labels this call-out "CAUTION" — reclassified NOTICE here as an equipment-only outcome
Consequence: The brush can be damaged or broken
Avoidance: Be careful not to damage or break the brush while inserting it and setting the brush cable
Hazard: Mounting the brush assembly without the alignment jig (step 13); source labels this call-out "CAUTION" — reclassified NOTICE here as an equipment-only outcome
Consequence: The brush sliding surface can extend beyond the ring
Avoidance: Mount the brush assembly using the brush alignment jig (BSX77-4283) so the brush sliding surface does not extend beyond the ring
Full step-by-step for Replace the large-current slip ring brushes
All 14 steps are documented in the FSELIB Aquilion 16 (TSX-101A) service manual — re-authored, web-first, with the real figures from the source.
Open the full procedureRelated Gantry — Slip ring & brushes guides
Source: 2D201-061E*H p.85-87. Preview re-authored by FSELIB — the full procedure with figures and steps is in the paid service manual.