minimum voltage to run A/C

In the US the standard Supply Voltage is 120, and the standard Utilization Voltage is 115, using the assumption that there can be a 5 volt drop between the utility point of connection and the device consuming the electricity. It's not very convenient to measure the voltage right at the air conditioner. I've found it's reasonable to assume a 2 volt drop in the air conditioner's circuit, so my convention is to measure the voltage at an unloaded outlet inside the RV (with the air conditioner running), and if it's 105.5 or higher, assume the air conditioner is at or above its manufacturer-specified minimum of 103.5 or higher.