When operating two aircraft AC generators in parallel, what must be equal?

When operating two aircraft AC generators in parallel, it is essential that both frequency and voltage are equal. This is because, for generators to operate in parallel without conflict, their output currents must combine seamlessly without causing issues such as circulating currents or instability.

Frequency is crucial because, in AC systems, the frequency of the electricity must be consistent to ensure that all electrical components receive power at the same rate. Different frequencies could lead to equipment malfunction or damage. Voltage must also be equal to ensure that there is no differential that could cause one generator to try to feed power back into the other, which could create a dangerous situation or system imbalance.

Amperage does not necessarily need to match between the generators when operating in parallel because they can share the load based on their individual output capabilities. However, if the frequency and voltage are not equal, it could lead to significant operational issues. Therefore, focusing on matching frequency and voltage is the correct approach when connecting generators in parallel.