Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×

Go Back   Montana Owners Club - Keystone Montana 5th Wheel Forum > MOC Technical Forums > Solar, Charging Systems, Batteries and Electrical
Click Here to Login

Thread Tools Search this Thread Display Modes
Old 08-18-2022, 05:36 PM   #21
Montana Master
Join Date: Jul 2020
Location: Battleford
Posts: 594
M.O.C. #26690
Originally Posted by rames14 View Post
This has been a great discussion. Living in the mountains, we donít have AC at the house and usually camp in high altitude. The 1200 watts of solar/540 ah of battery, keep us well supplied. Until we boondock somewhere like Moab when itís 104. I think weíll stick to the mountains in summer. Now before I retired, the Midwest was a different story. More like what Mike sees. This will continue to evolve. In the mean time, I will be interested to see how this turns out. And Brad, hope that outdoor kitchen is getting a workout.
LOL, yes indeed it has!
I have fed 20 people or more on multiple occasions. We went 10 days in July and our site was the "cook house". We made wings, ribs, brisket, smash burgers; it was great. I even had a vegetarian stop by who tried some of the brisket and had to phone his wife to tell her how great it was.
Thanks for remembering

Sorry for the OT, Mike, back to regularly scheduled programming...

2021 Montana 3790RD, Legacy, Super Solar Flex
2020 RAM 3500 Limited, HO
kowbra is offline   Reply With Quote
Old 08-19-2022, 05:57 AM   #22
Montana Fan
Join Date: Aug 2020
Location: Weddington
Posts: 126
M.O.C. #26813
Hello Brad,

Thank you for your input, it is greatly appreciated. As I lie awake at night considering all this, I think my best option may be to relocate the original batteries back next to the new ones so they can all be together and properly wired. Any reduction in pin weight is a plus for me. I know the run is long but I would add another set of 4/0 cables to keep the losses low. As soon as I have some data with the new SmartShunts I will post it here.

Hello Ed, yes, I did all this work myself and this is why a value everyone's input greatly. I have done many other upgrades as well (stand alone in-cabinet icemaker install, 400 watt Kicker stereo upgrade including amp, speakers and subwoofer, HAM radio power and antenna feed lines, Honda 2200 generator permanent install w/ propane conversion, hard piped water filter and softener, full width cargo tray, additional motion lights throughout the basement and front storage, under carriage colored LED strings on a dusk/dawn controller, See-Level tank gauges, removed the kitchen table and bolted down a powered up/down desk, washer/dryer... and more).

I also had to fix a lot of problems that should have been done at the factory: I mounted the recliners to the floor with 4 bolts each instead of just one screw (during this project I found the couch was held in place by just one screw as well!), rebuilt the under bed storage as the staples on the sides started to fall out and the bottom did fall out, installed the correct heat pump controller so the rear A/C would actually pump heat... I could go on.

I am a big believer in DIY so when things go wrong in the future, and they will with an RV, hopefully I can troubleshoot and fix it myself.

Best Regards, Mike
Mike & Doreen
2021 Montana 3120RL Legacy - Sterling - Super Solar
2020 Chevy 2500HD High Country
MAWilsonPE is offline   Reply With Quote
Old 08-21-2022, 04:00 PM   #23
Established Member
nsdtr3's Avatar
Join Date: Jun 2018
Location: Corvallis
Posts: 35
M.O.C. #22012
You've done an amazing upgrade to your Montana. Love hearing about them. Best to you.

John and Marie
nsdtr3 is offline   Reply With Quote
Old 08-25-2022, 01:52 PM   #24
Montana Fan
Join Date: Aug 2020
Location: Weddington
Posts: 126
M.O.C. #26813
Battery Imbalance Testing

I installed two SmartShunts, one near the front pair of batteries and one near the new rear pair of batteries in order to measure the amps flowing from each pair during a discharge and charge cycle. I am shocked at how much the front pair draws and charges first leaving the rear pair way behind in the cycle. As many as 3x the amps flowed from (or to) the front pair vs. the rear.

For my first test I ran one A/C unit for 3 hours until the front pair of batteries discharged to 50% taking readings every 10 minutes. The rear pair discharged only to a level of 80%. I had the solar turned off so the test would be as simple as possible.

I then plugged in to shore power, still with the solar off and charged the batteries at a rate of about 120 amps (DC). Again, the front pair took most of the charge although both sets reached 95-97% pretty much at the same time. Once the front pair hit 97% the amps went preferentially to the rear. Once the system went into absorb charging, the flow was about the same to both. This is because absorb charging is done at only a few amps and the losses to the back are minimal. See the numbers below.

In summary, a worthwhile test. I cannot tolerate any more weight in the front of my unit so I am now in the process of moving the front pair of batteries to the rear where I will close couple them with the new pair. I will run another set of 4/0 cables to the front to minimize the losses. Not an ideal set up due the long run between the batteries and the inverter but this will eliminate this imbalance issue and give me full use of the amp-hr capacity of all four batteries.

Best Regards, Mike
Attached Thumbnails
Click image for larger version

Name:	Screenshot (32).png
Views:	4
Size:	37.3 KB
ID:	12890   Click image for larger version

Name:	Screenshot (33).png
Views:	2
Size:	38.7 KB
ID:	12891  
Mike & Doreen
2021 Montana 3120RL Legacy - Sterling - Super Solar
2020 Chevy 2500HD High Country
MAWilsonPE is offline   Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Powered by vBadvanced CMPS v3.2.3

This website is not affiliated with or endorsed by Montana RV, Keystone RV Company or any of its affiliates. This is an independent, unofficial site.

All times are GMT -6. The time now is 04:35 PM.

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2022, vBulletin Solutions, Inc.