What is an essential characteristic of frequencies when paralleling transformers?

An essential characteristic of frequencies when paralleling transformers is that they must be the same. When transformers are connected in parallel, they need to operate at the same frequency to ensure that they effectively share the load and function harmoniously. If the frequencies differ, it can lead to issues such as circulating currents and unequal load sharing between the transformers, which may cause overheating and potential damage.

When transformers are designed to work together, they depend on a synchronized frequency to maintain stability and ensure that the output voltages align properly. Differences in frequency could also result in a phase shift, which can further complicate the situation.

In contrast, while slight variations in parameters such as voltage levels and impedance may be tolerated, the frequency must remain constant. Therefore, ensuring that the transformers operate at the same frequency is crucial for their safe and effective parallel operation.