Technical Summary
Commissioning is the last opportunity to detect cable compartment defects before the equipment is energized. Once voltage is applied, a missed bend-radius violation, loose bushing connection, or unsealed conduit becomes a live fault — not a punch-list item. This checklist reflects the highest-frequency findings from field experience.
1. Electrical Integrity
| Inspection point | What to check | Common finding |
|---|
| Stress cone seating | Fully engaged on the bushing, no gap, no tilting. Verify against termination manufacturer installation guide. | Cone not fully seated; partial discharge risk at the bushing interface |
| Bushing terminal torque | Verify every bolted connection with a calibrated torque wrench against the connector manufacturer specification. | Under-torqued (loose → heating → thermal runaway) or over-torqued (stripped threads) |
| Grounding connections | All ground conductors landed, labelled, and tight. Bonding jumper between compartment barrier and enclosure present and intact. | Missing bonding jumper; ground path relies on incidental metal-to-metal contact |
2. Mechanical Integrity
| Inspection point | What to check | Common finding |
|---|
| Cable support brackets | Tight, aligned, and visibly carrying cable weight. No cable hanging from bushing terminal alone. | Bracket loose, missing, or positioned too far from termination to be effective |
3. Environmental Protection
| Inspection point | What to check | Common finding |
|---|
| Conduit seals | Installed, compressed, no visible gaps. Expanding foam is not an acceptable permanent seal — use a removable waterproof compound. | Missing or improperly sized seal; provides direct path for water and pests from the duct bank |
| Door gasket integrity | Continuous around the full perimeter, not compressed flat, no cuts or tears. | Gasket pinched or folded during door installation; leaves an unsealed gap |
4. Documentation
| Inspection point | What to check | Common finding |
|---|
| As-built measurements | Record actual torque values, bend radius measurements, and ground resistance readings on the checklist form. | No recorded values — only checkmarks. If a termination fails later, there is no evidence it was correctly installed. |
5. Operational Readiness
| Inspection point | What to check | Common finding |
|---|
| Compartment cleanliness | No debris, tools, wire clippings, metal shavings, or standing water anywhere in the compartment. Sweep the entire compartment floor and check behind cables. | Metal shavings from conduit cutting — potential short-circuit path between phases or to ground once energized |
6. Post-Commissioning Documentation
Every inspection point should be initialled with the date and — where applicable — the measured value. This serves as warranty evidence (proving installation met manufacturer requirements at energization) and as an asset management baseline for future periodic inspections and trend analysis.
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