A/C tripping the breaker

Rthomas61 wrote:
What would cause the low voltage?

Load on the system - yours and everyone else's - excessive voltage drop from too long a cable run, excessive voltage drop from using cable inadequately sized for the task at hand. It ALL counts. ;)

Check it at the campsite post, both unloaded (i.e. before you plug in) and loaded (with everything running) AND at the camper when the circuit is under load. You can bet that if your unloaded source voltage is any less than 110 vac you can expect voltage under full load to be low enough to cause problems starting and running your A/C.

Here's a handy, easy to use Voltage Drop Calculator.