Infrastructure Engineering · Lesson 24 of 24 · 40 minutes

Audit the correction before releasing the design

The final lesson asks for a justified release decision, not the largest possible green score. Bring capacity, connectivity, protection, thermal behaviour, controls and evidence together. Then audit a proposed correction from the manuscript’s separate campus example: a remedy is another engineering assertion and must be recalculated.

Learning objectives

• Assemble a cross-system acceptance matrix.
• Reject a proposed remedy that still fails its capacity or current screen.
• Preserve source namespaces and unresolved evidence in the final decision.

Predict → run → explain

1. Read the declared boundary and units. Predict the selected result before calculating.
2. Run the starting case and inspect the ledger, assumptions and model limits.
3. Apply the challenge, run again, and explain the difference. Export only the last completed inputs and results.

Available MVA per side = (units per side − unavailable) × unit MVA; full-load A = unit MVA × 1,000/(√3 × kV); margin A = incomer A − full-load A. Capacity and current are independent necessary screens; design release remains HOLD.

Declared starting inputs

{
  "demandMVA": 560,
  "unitMVA": 250,
  "unitsPerSide": 3,
  "unavailable": 1,
  "voltageKV": 22,
  "incomerA": 6300
}

Challenge

Does correcting the transformer count close the whole design?

{
  "unitsPerSide": 4
}

Surviving capacity becomes 750 MVA, but the 6,300 A incomer still falls below approximately 6,560.80 A. Other required studies remain unresolved, so the design-release outcome remains HOLD.

The evidence-controlled release gate — static equivalent

1. Open the twenty-megawatt review matrix without mixing it with the separate campus case.
2. Switch to the campus remedy, remove one transformer and expose the remaining shortfall.
3. Recalculate a changed unit count while keeping the independent current issue visible.
4. Assemble six explicit gate states; unresolved or failed evidence leads to HOLD.

Six-condition acceptance matrix with blocking reasons and a source-qualified case register.

Choose pass/fail/unresolved for six justified criteria; require a reason and source locator before exporting the review.

Narrative steps are not physical seconds. Essential states and quantities remain available without animation.

Assessment and answer criteria