System

The {{entity:Industrial Elevator Control System}} ({{hex:51F77A58}}) at 132 requirements and 118 trace links. This QC session entered with DECOMPOSITION_STATUS = qc-reviewed and a quality gate deficit: 25/127 requirements were orphaned (no trace links) and all 25 were homeless (no document assignment). The session focused on eliminating the orphan deficit and addressing the five high-severity lint findings.

Findings

Orphans: 25/127 requirements (19.7%) had no trace links. Of these, 11 were ARC requirements, 5 IFC, 6 SUB, and 3 VER. All 25 were also homeless — not assigned to any document section, meaning they were invisible to linkset enforcement.

Document assignment: All ARC requirements ({{sys:ARC-REQ-001}} through {{sys:ARC-REQ-011}}) lacked a document home. Same for IFC-REQ-012/013/014/019/022, SUB-REQ-017/020/021/027/029/031, and all 26 VER requirements. The verification-plan document had been scaffolded as “verification-requirements” (not “verification-plan”) — its section ID section-1774127712520 was used for all VER reassignments.

Linkset gap: No linkset existed between system-requirements and architecture-decisions, so trace links from SYS to ARC were blocked. Two linksets were created (bidirectional) to enable ARC traceability.

High-severity lint findings — 5 findings, 3 resolved this session:

• {{entity:position monitor}} ({{hex:54840008}}) and {{entity:safety output actuator}} ({{hex:D6E57058}}) both carry the {{trait:Powered}} trait but had no power budget requirements. Two new requirements created: REQ-SEINDUSTRIALELEVATOR-011 (24V/5W position monitor supply spec) and REQ-SEINDUSTRIALELEVATOR-012 (24V/2A safety output actuator with 50ms brownout tolerance).
• Ontological mismatches for {{entity:industrial elevator control system}}, {{entity:safety controller}}, and {{entity:motor control unit}} (all lack {{trait:Physical Object}} trait but have physical embodiment). Three new physical embodiment requirements created: REQ-SEINDUSTRIALELEVATOR-013 (IP54 cabinet), REQ-SEINDUSTRIALELEVATOR-014 (SIL 3 safety controller DIN-rail separation), REQ-SEINDUSTRIALELEVATOR-015 (MCU PCB integration with VFD).

Spray pattern: {{sys:SYS-REQ-003}} (overspeed, SIL 3) accrued 16 outbound trace links — the highest of any requirement. This is justified: a SIL 3 safety requirement in a SIL 3 elevator controller legitimately cascades to every safety-critical subsystem (speed monitor, brake, safety CPU, interlock monitor, seismic interface, power supply, door safe state). Link rationales documented on each.

Verification coverage: 26/132 requirements (20%) have ‘verifies’ trace links. Activity coverage remains 0% — verification activities require a dedicated validation session. The 50% coverage target for SUB+IFC before marking qc-reviewed is not yet met.

Corrections

• Reassigned 11 ARC requirements → architecture-decisions section
• Reassigned 5 homeless IFC requirements → interface-requirements section
• Reassigned 6 homeless SUB requirements → subsystem-requirements section
• Reassigned 26 VER requirements → verification-requirements section
• Created SYS↔ARC linkset to unblock 12 ARC trace links
• Created 37 new trace links (25 orphan repair + 12 new requirement links), total 81→118
• Created 5 new requirements addressing power budgets and physical embodiment gaps
• Tagged 11 ARC requirements as informational,architecture-decision
• Deleted duplicate SUB-REQ-038 (duplicate of REQ-SEINDUSTRIALELEVATOR-013, same physical cabinet text)
• Created baseline QC-2026-03-22 (BL-SEINDUSTRIALELEVATOR-008)

Decomposition

flowchart TB
  n0["Industrial Elevator Control System"]
  n1["Traction Drive Subsystem"]
  n2["Safety Controller Subsystem"]
  n3["Door Operator Subsystem"]
  n4["Group Dispatch Controller"]
  n5["Power Distribution Subsystem"]
  n6["Building Integration Gateway"]
  n7["Building Management System"]
  n8["Fire Alarm Panel"]
  n2 -->|Brake permit, STO| n1
  n2 -->|Interlock status| n3
  n4 -->|Target floor| n1
  n4 -->|Door commands| n3
  n5 -->|3-phase power| n1
  n6 -->|BMS commands| n4
  n6 -->|Fire relay| n2
  n7 -->|BACnet/IP| n6
  n8 -->|Hardwired relay| n6

Residual

• 3 high-severity ontological mismatches remain in lint (system, safety controller, motor control unit lack Physical Object trait in the UHT classifier). Requirements for physical housing have been created but the classifier hex codes are not updated — this is an entity reclassification task.
• Verification coverage at 20% trace link / 0% activity. A SE_VALIDATION session is needed to build out verification activities across the 63 SUB+IFC requirements.
• 63 medium-severity lint findings remain (coverage gaps where STK concepts have no SYS derivation and SYS concepts have no SUB decomposition).

Next

Verification coverage is the remaining QC gap. The next session should run a SE_VALIDATION pass: build verifies linksets for the 40+ SUB/IFC requirements lacking VER trace links, with specific attention to the SIL 3 safety chain ({{sub:SUB-REQ-001}} through {{sub:SUB-REQ-012}}) and the power distribution requirements ({{sub:SUB-REQ-017}}/{{sub:SUB-REQ-020}}/{{sub:SUB-REQ-021}}).