Reply
 
Thread Tools Search this Thread Display Modes
 
Old 05-24-2020, 02:46 PM   #1
Senior Member
 
Join Date: Oct 2017
Location: SoCal
Posts: 148
Default Improved charging for storage batteries

Renogy DC-DC Charger wiring diagram-compressed.pdf
We generally camp where we have electrical hookups but sometimes we want to live off the batteries for a couple of days. We do not have solar at this point but I may consider adding it in the future.

I have not been satisfied with the ability of the WFCO Converter Panel to properly charge the batteries. I have never seen a charging voltage of over 13.6VDC and generally it floats at 13.1-13.2VDC. Consequently my two deep cycle batteries never have a full charge and are probably closer to 70%. In the future I may replace the deep cycle marine batteries with AGM or lithium to gain more capacity.

I researched possible chargers and discovered that Renogy (known for their solar equipment) sells a 20 Amp DC-DC Charger which is intended for use on a Class A, B or C motor home to charge the "House Batteries." It is capable of charging lead acid, Gel, AGM and Lithium batteries depending upon switch selection. They are priced a little more than $100 on Amazon so I purchased one. I also ordered the optional temperature probe so that the Renogy Charger can compensate for the temperature of the battery. The description is "Renogy Battery Temperature Sensor Battery Temperature Sensor on-board Battery Charger."

Also I purchased a Battery Switch capable of handling 2 batteries with an OFF position. Mine is made by Blue Sea. I found it expedient to purchase 3 sets of 20-Inch Battery Inverter Cable Sets and a 8/10 Gauge AWG in-Line AGU Fuse Holder with 40 Amp Fuse.

I added a Charger Switch so that the Renogy can be set to not charge regardless of the Battery Switch position. This is technically not required as I wired it so that the Renogy will only charge when power is available at the input positive terminal of the Charger. The ignition switch in the truck controls the power going to the trailer connector. This means that when the truck is OFF that the Renogy likewise turns OFF.

The new system performs as I have always wanted,
1) When towing I leave the Battery Switch in the OFF position with the Charger Switch ON. The Renogy boosts the voltage from my truck to properly charge and maintain the batteries.
2) When camping and AC is available I set the Battery Switch to Battery 2 and the Charger Switch to ON.
3) When dry camping without external power I set the Battery Switch to Battery 1 and the Charger Switch to OFF.
4) When storing the battery I switch the Battery Switch to OFF and the Charger Switch to OFF.
There is a bright green LED on the Renogy Charger which shows when it is active.

I have attached my wiring diagram and several photos of the installation. The Inverter was already supplied by FunFinder on my model. The 4 AWG cables between the batteries and connecting to the Inverter were all OEM.

This project was an outgrowth of my investigation to determine why my Odyssey AGM batteries failed in my truck. I discovered that a normal automotive alternator will not properly charge an AGM battery unless the internal regulator is changed so that it charges to a higher voltage. This led me to understand why the deep cycle trailer batteries exhibited such poor amperage capacity.
Attached Thumbnails
20200513_141601.jpg   20200520_125719.jpg   20200520_132747.jpg   20200520_150456.jpg   20200520_150858.jpg  

20200520_150551.jpg  
__________________

__________________
2016 F281BIKS
2003 F250 7.3L Powerstroke Crewcab longbed
JimboFunFinder is offline   Reply With Quote
Old 05-25-2020, 06:20 PM   #2
Senior Member
 
Join Date: Oct 2017
Location: SoCal
Posts: 148
Default

Here is a label which I made to help me remember the switch modes.
Attached Thumbnails
Battery Selector Switch label.JPG  
__________________

__________________
2016 F281BIKS
2003 F250 7.3L Powerstroke Crewcab longbed
JimboFunFinder is offline   Reply With Quote
Old 05-26-2020, 05:34 PM   #3
Senior Member
 
Join Date: Feb 2012
Location: Southern California
Posts: 1,663
Default

Great project, and great report -- thanks for posting this!!
__________________
2012 Fun Finder X-139 "Boondock Style" (axle-flipped and extra insulation)
2013 Toyota Tacoma Off-Road (semi-beefy tires and components)
profdant139 is offline   Reply With Quote
Old 05-26-2020, 05:46 PM   #4
Senior Member
 
Join Date: Oct 2017
Location: SoCal
Posts: 148
Default

Thanks!
I just want the FF to be as functional as possible which includes getting the most life from the storage batteries when we are camping without hookups. There is no way the truck's alternator puts out enough voltge to charge the deep cycle batteries while towing.
__________________
2016 F281BIKS
2003 F250 7.3L Powerstroke Crewcab longbed
JimboFunFinder is offline   Reply With Quote
Reply

Tags
agm, converter, deep cycle, lithium battery, wet cell

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by Fun Finder RV, Cruiser RV, or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 07:22 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
×