A/C short cycling

We found our large roof A/C had tripped its circuit breaker while we were gone from the Rv park. It restarted without a problem. Then during the night, the unit began to turn on and off in a matter of seconds, and would not continue running. we're not sure if the electricity was cutting on and off or not as we sleep without lights during the night. We turned the unit off before it could trip the breaker. My husband says it is probably low of freon. Is that the usual problem or can there be other problems with the unit or with the wall thermostat? We will take it in for repairs if necessary but would like to have an idea of what the problem could be first. Thanks for any information you can give us.