patrickg
Veteran Member
Re: ballancing the generator and 120/240
alco141, There may be more than just the two problems you mentioned, depending on the AirConditioner in question. If the unit isn't "soft start" or at least a "scroll" compressor the locked rotor or starting surge current may be something like 4-5 times the run current. 5000 watt gennys (likely an absolutely max short period rating) probably won't source 50-60 amps too well to start some RV A/C units and could "pop" a breaker trying.
In the "typical" RV installation, battery charging is provided by an auxiliary function of the "converter" which provides 12 VDC when you are plugged into "shore power" or are running the genny. These battery charging functions are pretty darned poor in most instances, a trickle charger at best. You might have a 12 VDC converter rated for 45, 65, or over 100 amps to run lights, radios, sat tv etc. but that is NOT how the battery is charged. It is a slow and innefficient method of battery charging to run a genny to power the converter to get the converter's charging circuit to charge the RV batteries.
You will get the job done much better and faster if you use a batery charger sized to charge the total amp hours of batteries to be charged at one time and power that charger from the generator. My converter AT BEST charges at 5 amps and as I have 325 amp hours at 12 volts that is way undersized. It is not too expensive to buy a good regulating (automatic adjusting) charger and be way ahead. You will save generator fuel and run time and you could save your or a neighbors nerves.
In my case, if battery charging were a perfectly efficient operation and my battery bank was at half charge, I would have to supply 162.5 amp hours to top it off. At a 5 amp rate that would be 32.5 hours. Battery charging is NOT 100% efficient so the actual time required is much longer. I use a 20 amp charger and wish I had bought a larger one. Your battery bank capacity and condition and built in charging rate will likely be different but this illustrated the main idea.
A parting shot: I sometimes camp where it is really dry (low relative humidity). For that situation I have a rooftop mounted swamp cooler (evaporative A/C) which uses about 5-6 amps at 12 volts depending on high or low speed. It is powered by the rooftop solar cells (up to 14 amps in bright sun) and boy are those solar cells quiet compared to the aux gen.
Patrick
alco141, There may be more than just the two problems you mentioned, depending on the AirConditioner in question. If the unit isn't "soft start" or at least a "scroll" compressor the locked rotor or starting surge current may be something like 4-5 times the run current. 5000 watt gennys (likely an absolutely max short period rating) probably won't source 50-60 amps too well to start some RV A/C units and could "pop" a breaker trying.
In the "typical" RV installation, battery charging is provided by an auxiliary function of the "converter" which provides 12 VDC when you are plugged into "shore power" or are running the genny. These battery charging functions are pretty darned poor in most instances, a trickle charger at best. You might have a 12 VDC converter rated for 45, 65, or over 100 amps to run lights, radios, sat tv etc. but that is NOT how the battery is charged. It is a slow and innefficient method of battery charging to run a genny to power the converter to get the converter's charging circuit to charge the RV batteries.
You will get the job done much better and faster if you use a batery charger sized to charge the total amp hours of batteries to be charged at one time and power that charger from the generator. My converter AT BEST charges at 5 amps and as I have 325 amp hours at 12 volts that is way undersized. It is not too expensive to buy a good regulating (automatic adjusting) charger and be way ahead. You will save generator fuel and run time and you could save your or a neighbors nerves.
In my case, if battery charging were a perfectly efficient operation and my battery bank was at half charge, I would have to supply 162.5 amp hours to top it off. At a 5 amp rate that would be 32.5 hours. Battery charging is NOT 100% efficient so the actual time required is much longer. I use a 20 amp charger and wish I had bought a larger one. Your battery bank capacity and condition and built in charging rate will likely be different but this illustrated the main idea.
A parting shot: I sometimes camp where it is really dry (low relative humidity). For that situation I have a rooftop mounted swamp cooler (evaporative A/C) which uses about 5-6 amps at 12 volts depending on high or low speed. It is powered by the rooftop solar cells (up to 14 amps in bright sun) and boy are those solar cells quiet compared to the aux gen.
Patrick
