How is a replacement selected?
Four decisions, taken in order, that narrow the choice to when to replace an AGL asset, with what, and how.
Every AGL asset is eventually repaired, refurbished, upgraded or replaced, and the aim is to renew on evidence of condition rather than on age alone. The whole-life cost compares repair with replacement, the match decides whether the new part is like for like or changes the circuit load, and the work is isolated first, then tested and recorded.
The flowchart only narrows the choice. The final decision is agreed against the owner’s asset-management plan for condition evidence and whole-life cost, and against the manufacturer’s data and site procedures for type, rating, connectors and testing.
Frequently Asked Questions
Q1How is an AGL replacement selected?
By working through a few decisions in order: what condition the asset is in, whether repair or replacement costs less over its remaining life, whether the new part is like for like or a new type, and how the work will be made safe, tested and recorded. The result is agreed with the owner’s asset-management plan.
Q2Why renew on condition rather than on age?
There is no single fixed service life that suits every asset. Ageing depends on the quality of the unit, the environment, the loading and the maintenance. Tracking condition, for example insulation-resistance trends, shows when failures are about to climb, so assets are renewed on evidence before they fail in numbers.
Q3Why compare whole-life cost?
The purchase price is only one part. Installation, energy, upkeep, spares, downtime and renewal all add up, so an option that is cheaper to buy but harder to repair, or that wears out sooner, can cost more over the same period. The cost of lost availability is included.
Q4What must be checked when the new part is a different type?
A different lamp type or wattage changes the output and the load on the isolating transformer, and every load adds to the total the CCR must supply. Changing the light source also changes lamp failures but not how cables, connectors, transformers and seals age, so each part is considered on its own.
Q5What should be checked before the choice is final?
That the evidence of condition supports replacement, that the whole-life cost has been compared over the same period, that the new part matches the type, rating and connectors or its load has been checked, and that the work is isolated, tested and recorded in the asset register. The manufacturer’s data and site procedures decide.
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