A ring main unit is signed off on evidence, not on a walk-round. This note sets out what IMAD hands over at commissioning and why each document is on the list.
The test regime
Every MV switchgear scope we commission runs the same five procedures before energisation, in the same order. Contact timing and resistance comes first, because a slow or high-resistance contact invalidates everything measured after it.
- Contact timing and resistance
- Insulation resistance at 5 kV
- Partial discharge analysis
- Protection relay verification against the approved settings file
- Primary injection on each protected circuit
What the pack contains
Test sheets signed by the engineer who performed the test, the relay settings file as applied, as-built single-line drawings, and the O&M manual for the installed equipment — not the generic manufacturer PDF.
A handover pack that cannot be audited two years later is not a handover pack.
Why it matters at tender
A plant engineer comparing two bids can read a sample handover pack in ten minutes and learn more than an hour of presentations would tell them. Ask for one.