Originally Posted by Cuttinchief
Thanks could you email me a link to a video or send me a wiring diagram? I have heard if you had a 6 battery bank you could run an A/C but I would like to operate all my outlets and save gas. I have the best generator a Honda 6500iu and my 5 er is all 120v and my Honda has a switch that will allow me to run everything on my RV at the same time to include both A/C units. I just want something that will allow me to operate my trailer without a generator except to charge my batteries. I just can't find a good enough how to guide to do it without burning my camper down HAHA.
Not sure what you are asking.
My wiring diagram is right below my post...
When you find a "how to guide" that will allow you to do that; and it weighs less than several thousand pounds; let me know too. I want one...
Lets say you want to run 2 15K AC units at the same time in your 50 amp coach. (I have actual data on my 15K air conditioner so I won't have to guess).
First, you will need 2 inverters; one to handle each leg of your 50 amp service. The battery bank, however, will "see" the load on both inverters at the same time.
Start-up current on the ACs (since they are inductive motors) run about 26-28 amps per unit and "mellow out" at about 15 amps per unit when up to speed.
If they both kicked on at the same time your peak load will be 28 amps x2 or 56 amps at 120 volts (nominal) or 6720 watts of power for about 15 seconds from your battery bank. (Your inverters must be rated at 3000 watts running with 3500 watts peak EACH to accomplish this feat.)
To create 6720 watts using 12 volts battery power, your bank will need to momentarily supply 6720/12 = 560 amps for about 15 seconds. Spread over 6 12 volt batteries 560/6 = 93 amps PER battery.
Suppose you have six FULLY CHARGED 160AH Trojans as your bank. That would be a 50% of capacity draw for about 15 seconds. Using the example chart below that plots the battery capacity reduction as a function of percent of total capacity (since it will plot out to the extreme far right of the curve), we will say your battery capacity would decline to 30%; and recover after 15 seconds to the run state of 15 amps (per AC) at 120 volts or 3600 watts.
To create the 3600 watts (running) at 12 volts would require what is left after starting the fan and compressor to supply the 50 runtime DC amps PER BATTERY to keep both ACs running.
30% of 165 AH = 50AH per battery as the capacity remaining after both ACs started. A 50AH draw on a 50AH (remaining) capacity battery will run dead in about 45 minutes or less depending on if there is something else going on (like running lights or the radio.
Trust me, your 6500 watt generator is doing all it can to run 2 air conditioners. Trying to replace your generator with a battery bank will require several banks of 6 heavy duty Trojans to get the "per battery" draw down to 25 AH each at the peak start up current demand.
6720 watts required at 12 volts 560 amps - divided by 25 amps nominal per battery = twenty three (or more) 165 AH batteries to give you all day (8 hours or so) relief.
Charging them would also be a problem. To REPLACE the amps you sucked out of 23 or 24 165AH batteries could take weeks with a dedicated battery charger.
Obviously if you could time the start of each AC so they don't try to start at the same time; it would not be so bad...