What occurs if a power transformer is overloaded for an extended period of time without proper voltage regulation?

When a power transformer is overloaded for an extended period without proper voltage regulation, potential equipment damage is a significant risk. Transformers are designed to operate within specific load limits and temperature ranges. When the load exceeds these limits, the transformer's internal temperature can rise beyond safe thresholds, leading to overheating.

As the temperature increases, the insulation materials that protect the windings can degrade, potentially leading to short circuits or complete transformer failure. Additionally, prolonged overload conditions can result in increased losses—both copper losses from higher currents and additional iron losses from excessive heat—which further exacerbate the risk of damage.

In contrast, overloads can lead to voltage drops and an increased risk of system instability, which complicates utility operations and may affect other connected equipment negatively. Thus, without voltage regulation or load management, the outcome of prolonged overloads is indeed the risk of equipment damage, making this the correct answer.