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 Search this Thread Display Modes
 
Old 10-30-2015, 10:43 AM   #1
Full Time Adventurer
 
BoldAdventure's Avatar
 
2007 27' International CCD FB
Nomadic , USA
Join Date: Jul 2013
Posts: 2,748
Lightbulb Upgrading to 6V Trojans - Series Parallel Wiring - Battery bank build

The time has come for this project. The plan; upgrade my existing two group 27 batteries to four 6v-Trojan AGM's wired in series parallel to create two big 12v battery banks.

This is how I intend to wire the batteries together:


I'll be moving my batteries from the tongue to the back of the front storage compartment. I might move them elsewhere within the bedroom based on feedback to this post.

For those who don't recall, our bedroom is a little different than the standard queen or twin. The front storage compartment also gained a few inches in depth.


And maybe I can get a few things sorted with your help.

I have read recommendations to use 4/0 class 'K' welding cable between the batteries. As I understand it, the Airstream's current direct connections to the main panel are 6 gauge. Curious if anyone thinks I should upgrade this to 2/0 or 1/0 gauge.

Currently, present between the battery and the Airstream is a 50-amp fuse breaker. Should I consider upgrading this to 80 or 100-amp?

I'll document the rest of this process in this thread as I make progress on the work. This week we are acquiring out batters and cables. And should be getting started next weekend.
__________________
Family of 5 exploring the USA with a Ram Power Wagon & Airstream in tow.
OUR BLOG | INSTAGRAM
BoldAdventure is offline   Reply With Quote
Old 10-30-2015, 10:52 AM   #2
Rivet Master
 
Mrjkq's Avatar
 
2016 25' Flying Cloud
Venice , Florida
Join Date: Apr 2015
Posts: 1,024
I have 4 trojans in my golf cart & they are awesome, good luck with your project.
__________________
Joe
Venice, FL
2016 FC 25RTB
TAC FL-47
2018 Nissan Titan XD Cummins Diesel
Mrjkq is offline   Reply With Quote
Old 10-30-2015, 11:31 AM   #3
Rivet Master
Commercial Member
 
Vintage Kin Owner
Naples , Florida
Join Date: Dec 2005
Posts: 7,508
Bold,

Since the series/parallel connections are essentially a continuation of the internal battery plate connections, I would go 4/0 for those.

I usually use 4AWG or 2AWG ( depending on run length) for the connections from the batteries to the bus bars. 50 amps for circuit protection is fine.

If you have an inverter. I would upgrade the direct connections for the battery to inverter with 1/0 ( again length dependent) using a 150 amp class T fuse.



Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357
__________________
lewster
Solar Tech Energy Systems, Inc.
Victron Solar Components and Inverters, Zamp Solar Panels, LiFeBlue and Battle Born Lithium Batteries, Lifeline AGM Batteries
lewster is offline   Reply With Quote
Old 10-30-2015, 12:29 PM   #4
Overland Adventurer
 
AtomicNo13's Avatar
 
1991 34' Excella
2009 34' Panamerica
Telluride , Colorado
Join Date: May 2012
Posts: 2,476
Bigger, cleanly terminated is better!
AtomicNo13 is offline   Reply With Quote
Old 10-31-2015, 09:14 AM   #5
Zil
4 Rivet Member
 
Curtis Wright
Currently Looking...
Eyren Haven , South Jersey
Join Date: Apr 2014
Posts: 326
I recommend you use marine cable rather than welding cable. You can even get it made to order with proper connectors. Such as 1 of many= Custom Battery Cable Assembly Custom Made Genuinedealz.com
Zil is offline   Reply With Quote
Old 10-31-2015, 10:19 AM   #6
Full Time Adventurer
 
BoldAdventure's Avatar
 
2007 27' International CCD FB
Nomadic , USA
Join Date: Jul 2013
Posts: 2,748
Thanks. I'm a huge fan of cutting and crimping my own wires so I only have myself to blame for most things. I'm leery of marine as I've purchased some before that were copper coated tin.
__________________
Family of 5 exploring the USA with a Ram Power Wagon & Airstream in tow.
OUR BLOG | INSTAGRAM
BoldAdventure is offline   Reply With Quote
Old 10-31-2015, 10:35 AM   #7
Overland Adventurer
 
AtomicNo13's Avatar
 
1991 34' Excella
2009 34' Panamerica
Telluride , Colorado
Join Date: May 2012
Posts: 2,476
Belden welding wire is the best bang for the buck. It is very high quality, fine stranded wire in a very durable neoprene/PVC jacket. It solders beautifully!
AtomicNo13 is offline   Reply With Quote
Old 10-31-2015, 10:51 AM   #8
2 Rivet Member
 
1989 32' Excella
Sharon Springs , New York
Join Date: Aug 2015
Posts: 75
Interested in doing such an upgrade next Spring ourselves, how much weight is added by using 4-6Vs vs. the code 27 batteries? We have 2-12V code 24s in the factory compartments one on each side of the A-frame in the body of the trailer, assuming its for even weight distribution, are you mounting them the same way? Sorry we can't add more towards your decision making process but will follow your thread and use it to plan our upgrade. Good luck and thanks for the idea...
Regards,
James and Rebecca
Easyrider06 is offline   Reply With Quote
Old 10-31-2015, 11:26 AM   #9
3 Rivet Member
 
2004 25' Safari
1999 27' Safari
1968 17' Caravel
Fountain Valley , California
Join Date: Mar 2011
Posts: 111
We did a similar project almost a year ago, only on a slightly smaller scale. Our 25' Airstream had two size 24 batteries and I switched them to two Trojan 6-volts. Increased capacity from approx. 80 AH per battery to approx 225 AH per battery (now 450 AH total instead of 160 AH total). What an incredible difference as we have solar and do mostly dry camping.
Cable size will be determined in part by how large of an inverter you will be using. We do not use our inverter for the microwave or electric coffee pot, so extra large wiring not an issue. The wire we used earlier for the inverter wiring was MARINE wire.
BATTERY CONVERSION NOTES:
Converted from (2) 24-sized batteries to (2) 6-volt golf cart batteries ((2) Trojan T-105 Batteries 2*($125-$10pickup+$20core)+$21.60 tax).
Items:
1. Replace the 3/8" threaded rod (I think I went from an 8" to a 10", or a 10" to a 12", can't quite remember). Rod replacement is not easy because it is threaded through a nut which is welded on the outside bottom of the battery box, and then the rod is seal welded to the nut. You have to grind off about half of the nut in order to be able to unscrew the existing rod. (With the "undercoating" on the bottom of the battery box this was not evident, so thinking that you could unscrew the existing rod took a lot of time. I called the AS factory and the technicians went out on the floor to examine the bottom of the battery box, but still didn't know that the rod was welded. You cannot use a 3/8" rod coupler to extend the rod, as there is insufficient room for the larger gap required between batteries.
2. The size 24 batteries sit in a plastic shell at the bottom of the battery box. My local AS dealer just removes it and leaves it out, if they do the conversion. For me, I removed it, then cut out both ends of the plastic shell so that the golf batteries would sit on plastic in the bottom of the box.
3. The battery box has to be heightened. This was not a problem for my AS, but if someone has a forward storage outside door, they would have to have the box extended down, instead of up as I did it. I had some 1"X3" oak, so i just made a 2 1/2" extension on the top of the box, and moved the lid up, and it was fine. (Our local AS dealer can fabricate a 2" or 2-1/2" box extension, but opted to make my own.)
4. The two new 6-volt batteries have to be wired in series, instead of in parallel as the 12-volt batteries were.
5. I had to use a pneumatic "nibbling" tool to enlarge the propane tank cover cutout to fit the taller battery box (i.e. trim away 2 1/2" of aluminum to make the propane tank cover slip over the two propane tanks and fit properly)
6. The golf cart batteries don't use automotive type posts, so I had to cut off the ends of the battery cables, buy a heavy lug crimper (on ebay about $25), and crimp on some lugs to fit the new battery studs.

Notes: I didn't re-weld the battery hold-down rod, I just used lock nuts on the bottom outside. Also, I took advantage of having the batteries removed and scraped the corrosion out and reprimed and painted the inside of the battery box.
WindyJim is offline   Reply With Quote
Old 10-31-2015, 12:45 PM   #10
3 Rivet Member
 
1974 25' Tradewind
Calgary , Alberta
Join Date: Jul 2015
Posts: 109
Quote:
Originally Posted by WindyJim View Post
We did a similar project almost a year ago, only on a slightly smaller scale. Our 25' Airstream had two size 24 batteries and I switched them to two Trojan 6-volts. Increased capacity from approx. 80 AH per battery to approx 225 AH per battery (now 450 AH total instead of 160 AH total). What an incredible difference as we have solar and do mostly dry camping.
If your Trojan 6-volts are rated at 225 AH each, you now have 225 AH at 12V total, not 450. If you programmed your chargers based on the 450 AH number (and/or if you do discharge percentage calculations based on that number) you are overestimating by a factor of two.
Alumineer is offline   Reply With Quote
Old 10-31-2015, 12:51 PM   #11
Rivets?
 
nvestysly's Avatar

 
1992 29' Excella
2010 22' Interstate
Van By The River , Georgia
Join Date: Feb 2002
Posts: 2,361
Quote:
Originally Posted by WindyJim View Post
We did a similar project almost a year ago, only on a slightly smaller scale. Our 25' Airstream had two size 24 batteries and I switched them to two Trojan 6-volts. Increased capacity from approx. 80 AH per battery to approx 225 AH per battery (now 450 AH total instead of 160 AH total). What an incredible difference as we have solar and do mostly dry camping.
Cable size will be determined in part by how large of an inverter you will be using. We do not use our inverter for the microwave or electric coffee pot, so extra large wiring not an issue. The wire we used earlier for the inverter wiring was MARINE wire.
BATTERY CONVERSION NOTES:
Converted from (2) 24-sized batteries to (2) 6-volt golf cart batteries ((2) Trojan T-105 Batteries 2*($125-$10pickup+$20core)+$21.60 tax).
Items:
1. Replace the 3/8" threaded rod (I think I went from an 8" to a 10", or a 10" to a 12", can't quite remember). Rod replacement is not easy because it is threaded through a nut which is welded on the outside bottom of the battery box, and then the rod is seal welded to the nut. You have to grind off about half of the nut in order to be able to unscrew the existing rod. (With the "undercoating" on the bottom of the battery box this was not evident, so thinking that you could unscrew the existing rod took a lot of time. I called the AS factory and the technicians went out on the floor to examine the bottom of the battery box, but still didn't know that the rod was welded. You cannot use a 3/8" rod coupler to extend the rod, as there is insufficient room for the larger gap required between batteries.
2. The size 24 batteries sit in a plastic shell at the bottom of the battery box. My local AS dealer just removes it and leaves it out, if they do the conversion. For me, I removed it, then cut out both ends of the plastic shell so that the golf batteries would sit on plastic in the bottom of the box.
3. The battery box has to be heightened. This was not a problem for my AS, but if someone has a forward storage outside door, they would have to have the box extended down, instead of up as I did it. I had some 1"X3" oak, so i just made a 2 1/2" extension on the top of the box, and moved the lid up, and it was fine. (Our local AS dealer can fabricate a 2" or 2-1/2" box extension, but opted to make my own.)
4. The two new 6-volt batteries have to be wired in series, instead of in parallel as the 12-volt batteries were.
5. I had to use a pneumatic "nibbling" tool to enlarge the propane tank cover cutout to fit the taller battery box (i.e. trim away 2 1/2" of aluminum to make the propane tank cover slip over the two propane tanks and fit properly)
6. The golf cart batteries don't use automotive type posts, so I had to cut off the ends of the battery cables, buy a heavy lug crimper (on ebay about $25), and crimp on some lugs to fit the new battery studs.

Notes: I didn't re-weld the battery hold-down rod, I just used lock nuts on the bottom outside. Also, I took advantage of having the batteries removed and scraped the corrosion out and reprimed and painted the inside of the battery box.
I'm interested in performing a similar upgrade and have been reviewing data sheets for flooded lead-acid as well as AGM batteries. I'm looking forward to following along with BoldAdventure when pictures and descriptions are posted. I will likely use AGM as I plan to install the batteries inside the trailer, under the couch. I'm familiar with putting two 6V batteries in series to obtain 12 V and hope to put two banks of series batteries in parallel to double the available capacity.

So... I'm not following your math. Trojan flooded lead-acid, T-105, 6V batteries are rated at 225 Ah (the 20 hour rate). Putting them in series doubles the voltage to 12V, but does not double the capacity. Putting batteries in parallel doubles the capacity. Please explain - perhaps I've overlooked something.
__________________
Lucius and Danielle
1992 29' Excella Classic / 2010 Interstate
2005 Chevrolet Suburban K2500 8.1L
2018 GMC Sierra K1500 SLT, 6.2L, Max Trailering
Got a cooped-up feeling, gotta get out of town, got those Airstream campin' blues...
nvestysly is online now   Reply With Quote
Old 10-31-2015, 02:26 PM   #12
3 Rivet Member
 
2002 25' Classic
Kalama , Washington
Join Date: Feb 2003
Posts: 187
You'll like it

We did this project a dozen yrs ago to store what our solar panels generate. The details today are a bit fuzzy but we used the existing compartments (after enlarging and taller doors) and built an inside chase for two batteries under the forward couch (sealed to inside/vented outside). This arrangement allowed short cables but made tongue weight a concern. As I recall, I calculated, then measured a new tongue weight w/in 60lbs. of max (and knew that I could further reduce by packing items aft of the axles). Battery maintenance is a bit of a pain, but doable… certainly worth the added performance if dry camping is a goal.
And yes, doubling 6 to get 12v does not double the amps. But two banks of 6v pairs that are paralleled does.
nwclassic is offline   Reply With Quote
Old 10-31-2015, 04:51 PM   #13
Full Time Adventurer
 
BoldAdventure's Avatar
 
2007 27' International CCD FB
Nomadic , USA
Join Date: Jul 2013
Posts: 2,748
Quote:
Originally Posted by WindyJim View Post
We did a similar project almost a year ago, only on a slightly smaller scale. Our 25' Airstream had two size 24 batteries and I switched them to two Trojan 6-volts. Increased capacity from approx. 80 AH per battery to approx 225 AH per battery (now 450 AH total instead of 160 AH total).
No you actually have 225 Ah

Quote:
Originally Posted by nvestysly View Post
So... I'm not following your math. Trojan flooded lead-acid, T-105, 6V batteries are rated at 225 Ah (the 20 hour rate). Putting them in series doubles the voltage to 12V, but does not double the capacity. Putting batteries in parallel doubles the capacity. Please explain - perhaps I've overlooked something.
You're on the right track, this is why I am wiring series parallel.

Series adds the voltage of the two batteries, but keeps the same amperage rating (also known as Amp Hours).



Parallel connections will increase your current rating, but the voltage will stay the same.



If you have two sets of batteries already connected in parallel, you can join them together to form a series.





You can learn more here: Trojan Battery Company
__________________
Family of 5 exploring the USA with a Ram Power Wagon & Airstream in tow.
OUR BLOG | INSTAGRAM
BoldAdventure is offline   Reply With Quote
Old 10-31-2015, 05:50 PM   #14
Rivet Master
 
2007 16' International CCD
Vintage Kin Owner
Somewhere , Colorado
Join Date: Dec 2010
Posts: 1,536
True that two 6V batteries in series does not double the amp hours.

But, two 6V golf kart batteries in series have about 225 amp hours, which is significantly more than the 160 amp hours available from typical 12V batteries wired in parallel.

For this reason alone it is an upgrade worth considering. We did it, and are very glad to have the extra in reserve.
field & stream is offline   Reply With Quote
Old 10-31-2015, 06:00 PM   #15
4 Rivet Member
Commercial Member
 
acstokes's Avatar
 
2009 30' Classic
Melbourne, FL , Searsport, ME
Join Date: Jul 2013
Posts: 309
Two Lifeline GPL-6CT AGM batteries will give you 300 a.h. for the same footprint as the Trojans.
__________________
Fred Stokes
RV Rearview Camera Systems, LLC
WBCCI #2810
acstokes is offline   Reply With Quote
Old 10-31-2015, 06:04 PM   #16
Full Time Adventurer
 
BoldAdventure's Avatar
 
2007 27' International CCD FB
Nomadic , USA
Join Date: Jul 2013
Posts: 2,748
Quote:
Originally Posted by acstokes View Post
Two Lifeline GPL-6CT AGM batteries will give you 300 a.h. for the same footprint as the Trojans.
And a 40% difference in price too.

And the problem I ran into here, is I called around to see if anyone had Lifeline's. And no one does. Nearest place is in Oregon and CA. Freight charges for 4 of them were $225.00. So if someone knows where I can get those without the freight charges. Seems I can order them online, but not get them in person.
__________________
Family of 5 exploring the USA with a Ram Power Wagon & Airstream in tow.
OUR BLOG | INSTAGRAM
BoldAdventure is offline   Reply With Quote
Old 10-31-2015, 07:05 PM   #17
Rivet Master
Commercial Member
 
Vintage Kin Owner
Naples , Florida
Join Date: Dec 2005
Posts: 7,508
Bold,

PM me, I think I have a solution for you. :-))


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357
__________________
lewster
Solar Tech Energy Systems, Inc.
Victron Solar Components and Inverters, Zamp Solar Panels, LiFeBlue and Battle Born Lithium Batteries, Lifeline AGM Batteries
lewster is offline   Reply With Quote
Old 10-31-2015, 07:14 PM   #18
3 Rivet Member
 
1974 25' Tradewind
Calgary , Alberta
Join Date: Jul 2015
Posts: 109
We are FAR from having to think about batteries but because our '74 Trade Wind has the battery compartment behind the curb-side axles, I'm thinking of the Trojan T-1275 as a useful upgrade to the run-of-the-mill 80 AH deep-cycle battery.

The T-1275 is spec'ed at 150 AH and only marginally larger than the 80Ah battery. I just need to see how much surgery will be required on the battery compartment.
Alumineer is offline   Reply With Quote
Old 11-01-2015, 01:16 AM   #19
3 Rivet Member
 
2004 25' Safari
1999 27' Safari
1968 17' Caravel
Fountain Valley , California
Join Date: Mar 2011
Posts: 111
Unhappy Corrections for Inaccurate Amp-Hr Information

I've had several folks advise me relative to my improper AH information in my Quote below.
I stated that with two 6-volt 225 AH batteries I now have 450 AH total, but the correction is that for two 6-volt batteries in series we wind up with a 12-volt system with a 225 AH capacity instead of the 450 AH I thought we had.
That being said, there is a noticeable, substantial improvement with the Trojan batteries over my previous system. I am advised by the battery supplier that the Trojans also have greater longevity than what I was getting out of the previous 12-volt deep-cycle batteries.

Quote:
Originally Posted by WindyJim View Post
We did a similar project almost a year ago, only on a slightly smaller scale. Our 25' Airstream had two size 24 batteries and I switched them to two Trojan 6-volts. Increased capacity from approx. 80 AH per battery to approx 225 AH per battery (now 450 AH total instead of 160 AH total). What an incredible difference as we have solar and do mostly dry camping.
Cable size will be determined in part by how large of an inverter you will be using. We do not use our inverter for the microwave or electric coffee pot, so extra large wiring not an issue. The wire we used earlier for the inverter wiring was MARINE wire.
BATTERY CONVERSION NOTES:
Converted from (2) 24-sized batteries to (2) 6-volt golf cart batteries ((2) Trojan T-105 Batteries 2*($125-$10pickup+$20core)+$21.60 tax).
Items:
1. Replace the 3/8" threaded rod (I think I went from an 8" to a 10", or a 10" to a 12", can't quite remember). Rod replacement is not easy because it is threaded through a nut which is welded on the outside bottom of the battery box, and then the rod is seal welded to the nut. You have to grind off about half of the nut in order to be able to unscrew the existing rod. (With the "undercoating" on the bottom of the battery box this was not evident, so thinking that you could unscrew the existing rod took a lot of time. I called the AS factory and the technicians went out on the floor to examine the bottom of the battery box, but still didn't know that the rod was welded. You cannot use a 3/8" rod coupler to extend the rod, as there is insufficient room for the larger gap required between batteries.
2. The size 24 batteries sit in a plastic shell at the bottom of the battery box. My local AS dealer just removes it and leaves it out, if they do the conversion. For me, I removed it, then cut out both ends of the plastic shell so that the golf batteries would sit on plastic in the bottom of the box.
3. The battery box has to be heightened. This was not a problem for my AS, but if someone has a forward storage outside door, they would have to have the box extended down, instead of up as I did it. I had some 1"X3" oak, so i just made a 2 1/2" extension on the top of the box, and moved the lid up, and it was fine. (Our local AS dealer can fabricate a 2" or 2-1/2" box extension, but opted to make my own.)
4. The two new 6-volt batteries have to be wired in series, instead of in parallel as the 12-volt batteries were.
5. I had to use a pneumatic "nibbling" tool to enlarge the propane tank cover cutout to fit the taller battery box (i.e. trim away 2 1/2" of aluminum to make the propane tank cover slip over the two propane tanks and fit properly)
6. The golf cart batteries don't use automotive type posts, so I had to cut off the ends of the battery cables, buy a heavy lug crimper (on ebay about $25), and crimp on some lugs to fit the new battery studs.

Notes: I didn't re-weld the battery hold-down rod, I just used lock nuts on the bottom outside. Also, I took advantage of having the batteries removed and scraped the corrosion out and reprimed and painted the inside of the battery box.
WindyJim is offline   Reply With Quote
Old 11-01-2015, 01:39 AM   #20
3 Rivet Member
 
gtc6452's Avatar
 
2015 27' Flying Cloud
2011 30' International
mooresburg , Tennessee
Join Date: Jun 2009
Posts: 206
Images: 6
has anyone tried the 6v interstate batteries?
gtc6452 is offline   Reply With Quote
Reply

Tags
batteries, inverter, parallel, series, solar, trojan


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Solar panels in series or parallel - but why not both? drboyd Generators & Solar Power 19 10-16-2017 08:39 PM
Series Parallel Battery Wiring - Which is correct? trekerboy Electrical - Systems, Generators, Batteries & Solar 22 01-01-2015 08:52 PM
Battery hook up, parallel or series iamscuba2 Furnaces, Heaters, Fireplaces & Air Conditioning 4 08-15-2011 09:33 AM
Parallel not-alike honda eu series generators malimish Generators & Solar Power 26 02-04-2009 10:26 PM
Series or parallel benwd Batteries, Univolts, Converters & Inverters 52 11-03-2007 08:19 PM


Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.



All times are GMT -6. The time now is 08:00 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.