BAS-409 Visual Aid Library
Figure-use rule
Each figure is an orientation and reasoning aid, not a project drawing. Learners must pair it with the current sequence, point list, wiring/piping documents, manufacturer instructions, and as-found evidence.
Normal-rule anchor
Version control must include more than editable code; generated, binary, platform, certificate, database, and field-installed artifacts need traceable configuration management.
Case overlay
A repository contains logic source but the deployed controller binary, station database, gateway map, and certificate are missing.
Calculation/evidence callout: Reconcile source, generated, deployed, backed-up, hashed, owned, and unknown configuration items.
Normal-rule anchor
A timestamped filename is not sufficient traceability when it does not connect reason, author, source, review, test, and deployed result.
Case overlay
Five files named FINAL are stored on a laptop and the running station cannot be matched to any of them.
Calculation/evidence callout: Verify version uniqueness, checksum matches, issue-to-commit-to-release coverage, and chronological consistency.
Normal-rule anchor
A small line diff can have large physical consequence, while a large generated diff may contain little semantic change; review follows behavior and risk.
Case overlay
A one-line default changes every VAV minimum airflow after regeneration of 300 controller files.
Calculation/evidence callout: Count affected assets/points/modes, estimate blast radius and rollback effort, and reconcile reviewer findings and approvals.
Normal-rule anchor
A release is a reproducible package with identity and evidence, not whichever file is currently open in an engineering tool.
Case overlay
Two programmers export controller binaries with different tool versions and produce nonmatching files from the same source.
Calculation/evidence callout: Compare dependency/tool versions, build checksums, manifest coverage, conflict resolution, and promotion status.
Normal-rule anchor
Rollback is engineered before deployment; a backup with unknown contents or restore time is not an adequate recovery plan.
Case overlay
A critical supervisor update is scheduled for a two-hour window, but the last restore test took three hours.
Calculation/evidence callout: Calculate window, stabilization, verification, and rollback timing; reconcile RPO/RTO and dependency readiness.
Normal-rule anchor
A successful download is not successful change; deployed identity, behavior, collateral functions, monitoring, and restoration must be proven.
Case overlay
The release loads without error but one controller remains on the old version and an operator override masks a failed output.
Calculation/evidence callout: Reconcile planned and actual targets/versions, tests, response times, overrides, alarms, accounts, and temporary conditions.
Normal-rule anchor
Urgency can compress workflow but does not erase identity, authority, backup, scope, monitoring, restoration, or retrospective accountability.
Case overlay
During a freeze event, an operator asks for an immediate temporary setpoint and alarm-delay change.
Calculation/evidence callout: Track elapsed decision/action/recovery times and reconcile temporary changes, expirations, approvals, and retrospective actions.
Normal-rule anchor
Drift is not automatically malicious or harmless; preserve evidence and determine source, authority, consequence, and recovery before overwriting it.
Case overlay
A nightly compare finds changed VAV setpoints, a new administrator, and one controller checksum mismatch.
Calculation/evidence callout: Calculate drift rate, affected assets, age, authorization coverage, and baseline reconciliation status.
Normal-rule anchor
Hidden dependencies become outages during restore or upgrade; every required component needs version, source, support, license, integrity, owner, and replacement path.
Case overlay
A station depends on an unsupported driver, an expiring certificate, and a vendor library stored only on one laptop.
Calculation/evidence callout: Calculate days to expiration/EOL, dependency coverage, compatibility results, and recovery-source availability.
Normal-rule anchor
Recovery is complete only when approved functions and as-left configuration are proven, stakeholders are informed, evidence is preserved, and open risks have owners.
Case overlay
A rollback restores comfort but leaves an old certificate, stale gateway map, and undocumented temporary admin account.
Calculation/evidence callout: Reconcile all configuration items, versions, functions, tests, temporary states, issues, owners, and archive records; critical gaps cannot be averaged away.