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


Reply
 
Thread Tools Display Modes
 
Old 11-05-2018, 03:14 PM   #1
New Member
 
tibi's Avatar
 
Join Date: Apr 2018
Location: Colorado
Posts: 5
Year: 1998
Coachwork: International
Engine: T444E
Rated Cap: Special Needs
Question Battery System/ Solar/ Isolator/ Help!

Hi there!
First, I want to express my gratitude for all the time and effort so many of you put into sharing your knowledge & experiences on this forum. I’ve learned so much so far thanks to your thorough explanations. Inevitably though, more and more questions arose and while I tried to find all the information out there, there are still some uncertainties and I would feel a lot more comfortable running this by youse.

Based on rough estimations using solar & electrical usage calculators and common sense we came up with this “ideal” set-up (I might use these exact products or similar):

3 x Deep Cycle GEL Battery 12 Volt 200Ah in parallel for 600Ah bank https://www.renogy.com/renogy-deep-c...12-volt-200ah/
These are rated 1000 cycles at 50% DOD, compared with same capacity AGM, rated 500 cycles at 50% DOD.
Batteries Cycle charging Voltage is 14.2V and Recommended Maximum Charging Current is 40A

2 x 300 Watt 24 Volt Monocrystalline Solar Panel - series or parallel?
https://www.renogy.com/renogy-300-wa...e-solar-panel/ - OR similar; I found the same configuration USA made frameless&semiflexible on Ebay for a lot cheaper. I like the idea of having them mold to the curvature of the roof instead of building a frame&brackets for rigid panels. But also, I’ve heard many people say “stay away from cheap panels”. And rigid seem to cool off better because they allow air flow underneath. But they stick out more. Recommendations?

The series vs parallel question is related to the next puzzle piece - the Charge controller. I’m leaning towards parallel because of the shading concern, but the thinner AWG used in series is also appealing. I was thinking 60A MPPT would be good in case we decide to add on another panel in the future. But is it too big for either 48(72)V/300W or 24V/600(900)W, and should I go with smaller/bigger CC to ensure ideal efficiency?

Charge controller - something like this https://www.amazon.com/DPJ-Charge-Co...ds=SRNE+ML4860
(I am so very open to other suggestions because the models out there seem to be multiplying with few reviews catching up)

KeyLine VSR battery isolator 140 A. I plan to fuse in both battery systems https://www.amazon.com/gp/product/B0...BGOVPAGN&psc=1
“Cuts in at 13.3 volts and cuts out at 12.8” - Any concerns I should have with the type of batteries I’ll be using? Is 140A right for my application or should I go higher amperage? Any better isolators out there?

Pretty much everything we need to power is 12V (fridge, maxair fan, lights, etc) but we will add in an inverter(/charger) for any possible AC needs. We’re installing a horizontal propane tank for furnace heat, hot water & stove/oven.
Thanks so much for taking the time to read this; I’m looking forward to your replies

tibi is offline   Reply With Quote
Old 11-08-2018, 07:14 AM   #2
New Member
 
Join Date: Oct 2018
Posts: 8
I don't see anything that stands out as a concern (But I'm pretty new myself) We used 4 sealed lead acid batteries (hoping that by the time these die, the lithium batteries will come down significantly in price). If I were to do it again, I would go with the lithium batteries and avoid the worry of making sure I did not drop below 50%. Yes the initial cost is more, but I think you will come out ahead after the first cycle of replacing the shorter life lead acid types.
Heleads is offline   Reply With Quote
Old 11-08-2018, 11:45 AM   #3
New Member
 
tibi's Avatar
 
Join Date: Apr 2018
Location: Colorado
Posts: 5
Year: 1998
Coachwork: International
Engine: T444E
Rated Cap: Special Needs
Quote:
Originally Posted by Heleads View Post
I don't see anything that stands out as a concern (But I'm pretty new myself) We used 4 sealed lead acid batteries (hoping that by the time these die, the lithium batteries will come down significantly in price). If I were to do it again, I would go with the lithium batteries and avoid the worry of making sure I did not drop below 50%. Yes the initial cost is more, but I think you will come out ahead after the first cycle of replacing the shorter life lead acid types.
I agree. Did a lot more research on Lithium batteries lately and now I'm leaning towards starting with 2 of Renogy's 12V 100Ah LiFePo and hopefully add on when the budget allows. I think the price has already started to come down and hopefully will continue to do so. At this moment they have them listed on Ebay for 798.99 (the best offer I could find out there, excluding the China or Taiwan made alikes - running for 600 ~650$ a piece with internal BMS). Rated 2000 cycles at 100%DOD and obviously a lot more with less discharge. They are so much better for all the known reasons than lead acid (they're 1/4 of the weight of above mentioned gel, a lot more compact, put out constant power + charge and discharge quickly) and in the long run will save us $$.

Yesterday I learned I have a 160 amp alternator, and 3 starting batteries in parallel - probably to supply both ac systems and the wheelchair lift which are now gone. Didn't notice it before, but there is a 3-stud diode on the back of the battery box in which the + from both the alternator and starting battery bank feed into. There is one available stud for the auxiliary BB.
I could just use that and forget about buying another isolator, but I would still like to be able to allow electric flow from auxiliary to starting BB if ever needed.

The general recommendation is to go with a higher rated isolator than my alternator amperage - seems that 200A is about the biggest I can find. So the above mentioned KeyLine or something like Add-A-Battery from BlueSea Systems (for max 120A alternator) would not work!? Does this relay type look cool? https://www.ebay.com/itm/Dual-Batter...q3-O:rk:5:pf:0
Any better ideas?

As for the inverter/charger - I think 2000w would be a safe bet.
Recommendations on a decent & well priced model?
This all seems like a good set up since we can charge our batteries from shore or generator(we don't plan to get one, but just in case), solar and alternator
tibi is offline   Reply With Quote
Reply

Tags
batteries, charge controller, isolator, newbie, solar


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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 03:16 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.