What does a 'VA' rating on a transformer indicate?

A 'VA' rating on a transformer refers to volt-amperes, which is a unit of measurement that represents the apparent power in an electrical circuit. It measures the amount of power that the transformer can supply to the secondary circuit, combining both the voltage and current without taking into account the phase difference between them. This makes it crucial for understanding how much power is available for use by the devices connected to the transformer.

Transformers are rated in VA because it allows technicians to determine the capacity of the transformer to handle loads effectively. When selecting a transformer for a specific application, the VA rating helps ensure that the transformer can provide sufficient power to its connected loads without risk of overheating or failure.

Understanding the VA rating is essential for safely and effectively utilizing transformers in various applications, as it directly relates to the efficiency of power distribution in a circuit.