What is a characteristic of a transformer with secondary coils connected in series?

When secondary coils are connected in series, the overall voltage output of the transformer increases. This is a fundamental principle of transformer operation, based on the turns ratio. Each secondary coil contributes to the total output voltage, so if you have multiple coils in series, each supplying its voltage, the voltages add together. This characteristic is particularly useful in applications where a higher voltage is required without changing the primary side of the transformer.

In contrast, connecting secondary coils in series does not inherently decrease efficiency or increase current draw; in fact, it allows the system to provide higher voltage while potentially maintaining the same power level, depending on how the system is configured. Therefore, the correct understanding is that the series connection allows for the generation of a higher voltage output.