What is transformer load?
A transformer's load is the power its secondary supplies to the light fitting it feeds. It should sit within the transformer's rating, and it also counts toward the total load on the series circuit.
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Transformer load is the power a series isolation transformer supplies to the fitting on its secondary: the lamp or LED unit and any electronics inside the fitting. Every transformer has a rated power, made in set sizes (for example 30/45, 65, 100, 150, 200, 300 and 500 W), and the fitting’s load should sit within it.
On a series circuit the load does not stop at the transformer. What the secondary draws is carried by the primary into the loop, so the CCR must supply the sum of every transformer’s load, plus the transformers’ own losses and the cable losses. Adding or changing a fitting therefore changes the circuit load and has to be checked against the CCR rating. An overloaded transformer runs hot, while a heavily underloaded one wastes capacity. Isolate and make the circuit safe under site procedures before changing a transformer or fitting.
Frequently Asked Questions
Q1What is transformer load in AGL?
The power a series isolation transformer supplies to the fitting on its secondary, meaning the lamp or LED unit and any electronics in the fitting. Its primary carries that load, plus the transformer’s own losses, into the series circuit.
Q2How does a transformer’s load relate to its rating?
The rating is the power the transformer is built to supply. The fitting’s load should sit within it, so the transformer is chosen with a rating suited to the fitting it will feed.
Q3Why does one transformer’s load matter to the CCR?
On a series circuit the loads add up. The CCR has to supply the sum of every transformer’s load, plus transformer and cable losses, so adding or changing fittings changes the circuit load and has to be checked against the CCR rating.
Q4What happens if a transformer is overloaded or heavily underloaded?
An overloaded transformer runs hotter and may not hold its fitting at full output, which shortens its life. A heavily underloaded one still works but wastes capacity and tends to make the circuit less efficient.
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