So I know I posted in other people posts my Phase 1 and Phase 2 build but never got the chance to post the entire completed project so figured I'd take the time to summarize and put many of you at ease and yes you read correctly this is a successful split battery bank upgrade! SO many advised against a split bank and I knew if done smart it could be done.
I challenged myself with this build with a few main goals in mind that I wanted to accomplish.
1) Lose as little storage space as possible being I have an FBT model and really wanted to avoid losing an entire storage bay.
2) Be able to utilize everything electrically in the AS including running my 15k BTU A/C unit and Microwave on battery power while on the road and not hooked up to shore power.
So I engineered the build adventurously and spoke to Battleborn and researched as much as possible to have minimal odds of this not working out. 1 year later and this project has been proven successful.
The MultiPlus II is the ideal inverter to handle what I wanted for my 50 amp breaker panel but couple issues with it that I saw. Unit was massive to fit in my AS and it would have required major rewiring. It also functions automatically and supplements shore power with battery power which is awesome but wasn't important for me if you are knowledgeable enough to manage the power usage and know what you are drawing for power when running on the inverters(s) simultaneously. Simple to calculate how much power draw each appliance you run is within good operating range of the inverters capabilities.
So what I did was keep the 1000w Progressive Dynamics Sinewave Inverter that was preinstalled in my rig for driver half side of the AS appointed to kitchen and bedroom TV outlets. Then I added a 2nd 2000w Progressive Dynamics Sinewave Inverter for the Passenger side half of the AS covering the outlets in the galley, the bedroom, and outdoor outlet plus the 15k A/C and MW oven. The beauty of the PD units is that the remote display tells you how many kW you are drawing to not overload them.
I additionally installed a subpanel in the bathroom under the sink which ties into a new 30 amp breaker in the main panel and took the original branch feeds of the 15k BTU A/C and Microwave off the main pain and tied into this subpanel which also is tied into the 2000w PD inverter. Ran new 6/2 Romex as necessary to tie it all together and then also ran new power cable from the main panel receptacle to the front storage bay where I also installed a new WFCO 70amp converter to power up all the batteries. Wanted this as close as possible to the bank to have as little voltage drop as possible when charging the batteries and also beefed up the cabling on the converter to the batteries. I get the full charging benefit of the converter and actually charges even a little over the 70amp output rating. Now also free'd up 2 more circuits on the main breaker panel if I wanted to run additional 120v A/C lines anywhere else in the AS.
The battery bank is split. 2 Battleborns in the original AS box and 3 of them in the storage bay. Used massive 4/0 welding cable to tie the batteries together with very short cable runs also to minimize voltage drop and avoid unbalanced charging to any of the 5 batteries in the chain. Drilled holes into the front storage compartment floor on left and right side of the new battery bank to tie together the other 2 batteries and shunts in the original box. Made a custom wooden box with black felt to hide the 3 batteries in the bay so not even noticeable and a very small footprint. Looks factory and also installed the heated switch externally on the box in the event I want to heat them. Same with the 2 batts in the standard box - stuck a SPST switch that fit perfectly in one of the pre-existing hole cutouts in that box.
Installed intake and outake exhaust fans located in the corner where all the electronics are with a SMART hometheater controller sitting on the bedroom table to control the fan settings. The fans are housed to dissipate heat as much as possible. Recently made a 4-1/2 inch hole cutout to install the intake fan in the passenger side storage compartment because I needed better airflow and to suck more cool air into the electronics bay. The outake fan (now upgraded to 2 fans - 1 fan design shown in the picture) pulls the air out into the front storage bay and if necessary I can open the outside storage door to expel the excess heat. This way the air keeps moving because the 2000w inverter produces quite a bit of heat when the A/C is powered through it. No issues running the 15k BTU A/C on the inverter with MicroAir softstarters. Have soft starters on both A/C's actually so I can run on 30 amp service off shore power or even on my 4500w portable Westinghouse inverter generator. The constant draw on the 15k BTU A/C is only 1.7 Kw using the inverter. I can run the A/C nonstop off the batteries for approximately 4.5 hrs if necessary however can't see that being needed if conservative with the tstat setting during the evening hours when settling for the night on the road in a Cracker Barrel or wherever. With the A/C power cycling, can likely get through an entire nights sleep but have yet to test this duration. The digital display of the 2000w inverter sits in the cabinet right over the stove in the galley so tucked away.
Victron Smartshunt and 30amp DC to DC charger also tucked in the compartment with the inverters. Yes the wiring could be cleaner but I didn't feel like cleaning up the mess AS did with their wiring. Just ridiculous this rats nest. Someday I will go in there and clean it up. There is a lot I got accomplished here in such a small package so wasn't easy.
Upgraded the stock 180w solar package on roof from AS to 515w up there using same style Legacy Zamp panels. Plus have a 180w Legacy suitcase I can plug in at the battery box for a total 700w. Used original combiner on roof with splitters at the ports to accommodate the additional solar panels. Kept just within the max wattage that the original combiner can tolerate and still using the measly 10awg wire that AS ran from there to the 12v
distribution panel in the corner where all the rest of the electronics are.
I have to still continue testing the system for long period load using the inverter(s). I'll see how much better the cooling is now with the additional intake fan. If still need better cooling, will add another fan under the passenger side storage compartment (cutting another 4-1/2 inch hole at the rear wall of one of the 2 cabinets under the bed to suck more cool air from the main cabin into the passenger storage bay where the intake fan is installed. Should lower a few more degrees when inverters are cranking but doing a quick test this week proved the newly installed single intake fan to help considerably then just having solely the dual outtake fans.
Hope my mods help some of you out there if you were ever considering doing something along the lines of what I accomplished.
Happy Airstreaming and Safe Travels!