Running Both Air Conditioners On 30 Amp System

I have a 30 amp system. I can run both at once with no modifications. Both compressors WILL NOT start at once. My electronic climate control will automatically shed off one then the other. I can even turn on the microwave when both are running and one will shed until it is shut off. I would think that this could be done manually as well. If you exceed the draw of the 30 amp breaker, it would probably trip.