Reply
 
Thread Tools Search this Thread Display Modes
 
Old 11-15-2011, 11:06 AM   #1
Road Geezer
 
Road Geezer's Avatar
 
2011 27' FB Flying Cloud
San Jose , California
Join Date: Jan 2011
Posts: 268
Images: 34
Blog Entries: 20
Upgrading Batteries

I want to increase the amp-hour capacity in our 2011 27FC. The installed grp24's simply don't have enough for our needs and require me to fire up our Yamaha 2kw generator too frequently.

I have checked dimensions of the battery box against a grp 27 I just bought and I'm sure that with a simple modification I can accommodate two grp 27's. The new ones will be wired in parallel just like the current batteries.

Question #1: Are any changes required to the electrical system required in order to accommodate the new grp 27's vs the grp 24's that came with our AS?

Question #2: Is there a meter I can install that will give me a reasonably accurate indication of the percentage capacity remaining in the batteries?

Thanks for your help,

Paul
__________________

__________________
As far as I know, this is the oldest I've ever been.
Road Geezer is offline   Reply With Quote
Old 11-15-2011, 11:09 AM   #2
Rivet Master
 
dznf0g's Avatar

 
2007 30' Classic
Oswego , Illinois
Join Date: Jul 2010
Posts: 9,408
Images: 5
#1 - No
#2 - TriMetric 2025RV (i think that's the model number)

Do you have the same front battery compartments as a Classic has. If you do, and you are going lead acid, Interstate make a group 29 which just BARELY fits, and I mean barely.
__________________

__________________
-Rich-

"If the women don't find you handsome, they should at least find you handy." - Red Green
dznf0g is offline   Reply With Quote
Old 11-15-2011, 11:15 AM   #3
Rivet Master
 
dznf0g's Avatar

 
2007 30' Classic
Oswego , Illinois
Join Date: Jul 2010
Posts: 9,408
Images: 5
Look for the group 29 deep cycle on this page

Interstate Batteries

Here is the trimetric site

TriMetric Battery System | Bogart Engineering

Got mine at forum member www.bestconveter.com
__________________
-Rich-

"If the women don't find you handsome, they should at least find you handy." - Red Green
dznf0g is offline   Reply With Quote
Old 11-15-2011, 11:35 AM   #4
CLOUDSPLITTER "Tahawas"
 
ROBERT CROSS's Avatar

 
2003 25' Classic
Zanadude Nebula , WNY
Join Date: Jun 2007
Posts: 11,153
Images: 1
The reasonably priced monitors I've been using since upgrading the batteries...
Bob
Attached Thumbnails
Click image for larger version

Name:	DSC07702.jpg
Views:	92
Size:	322.5 KB
ID:	145261   Click image for larger version

Name:	DSC07699.jpg
Views:	93
Size:	318.6 KB
ID:	145262  

__________________
PFC.....

“After all these years the reason I continue to love Thanksgiving.....I still sit at the kids table.”
RLC

Sandra wanted to go to Cleveland on vacation,
but I’m the Husband, so we went to Cleveland.
RLC
ROBERT CROSS is offline   Reply With Quote
Old 11-15-2011, 11:57 AM   #5
Rivet Master
 
dznf0g's Avatar

 
2007 30' Classic
Oswego , Illinois
Join Date: Jul 2010
Posts: 9,408
Images: 5
Quote:
Originally Posted by ROBERT CROSS
The reasonably priced monitors I've been using since upgrading the batteries...
Bob
I guess it depends on what level of detail you want. TriMetric goes about as far in depth as you want with a lot of diagnostic aids. Well worth the money if you want that level of detail and accuracy.
__________________
-Rich-

"If the women don't find you handsome, they should at least find you handy." - Red Green
dznf0g is offline   Reply With Quote
Old 11-15-2011, 01:16 PM   #6
Rivet Master
 
Gene's Avatar
 
2008 25' Safari FB SE
Grand Junction , Colorado
Join Date: Sep 2007
Posts: 10,840
Paul,

I replaced the Series 24 OEM wet batteries with Lifeline Series 27 AGM's and had to modify the battery box. The box is probably the same as on our '08 Safari FB.

I removed the cover—that was the easy part. There's a lip underneath the cover hinge and I cut it with a grinding wheel on a drill. The wheel was poor quality (Ace hardware brand) and it took forever. If I had to do it again I'd use a carbide tipped blade on a Sawzall.

The AGM's cost a lot more, but they last a lot longer and have no water issues since they are sealed.

If you want to go solar, the solar controller will have a meter that measures battery voltage, but that's a lot more expensive than a meter.

I am attaching a voltage chart that tells you percentage of capacity.

Gene
Attached Thumbnails
Click image for larger version

Name:	voltchart1.gif
Views:	85
Size:	6.4 KB
ID:	145269  
__________________
Gene is offline   Reply With Quote
Old 11-15-2011, 03:23 PM   #7
Rivet Master
 
1975 29' Ambassador
Reno , Nevada
Join Date: May 2003
Posts: 1,351
State of charge is measured with either voltage or specific gravity. With a modern DVM, there is no need to delve into hazmat territory needed for specific gravity measurements.

The electron counters like the Trimetric need proper programming and can be deceptive. They calculate net energy flow and only infer current state of charge. The precision they indicate is way beyond any accuracy of the measure.

Voltage is really all you need. For best results, measure the voltage of a quiet battery - one that hasn't had any significant charging or discharging for at least a half hour. The chart is nice but all you really need to know is that you need to start thinking about a battery charge when the voltage gets down to 12.4, charging needs to be put on the priority list when it gets down to 12.2 and you should not let your batteries get below 12.0v.

You can also get a good idea of battery condition by watching how the voltage responds to loads like the water pump or furnace. A battery in good condition won't show much drop and will recover quickly. (note that battery condition and state of charge are two different things)

Factors like age, cycle to cycle variation, temperature, and use profile can each influence available battery capacity by more than ten percent. Measures more accurate than this are suspect and any changes on this order are not going to make much of a difference.

Battery energy capacity is a function of weight. Changes like from a group 24 to a group 27 or even to a T105 sized battery are within the nominal variations you can find in battery use so don't expect much.

The best thing you can do for better battery satisfaction is to upgrade your charging and maintenance equipment. Upgrade your OEM converter to one that does multiple stage charging and knows about battery storage maintenance like the ChargeWizard or Iota.

If you find you want a significantly bigger power budget, you need to think about a different RV. Those 24 ton class A's are big enough to carry a half ton or more of battery. A 4 ton Airstream TT isn't usually suitable for such a load so they keep it down to the 100 to 150 pound range for their battery bank.
__________________
bryanl is offline   Reply With Quote
Old 11-15-2011, 03:39 PM   #8
CLOUDSPLITTER "Tahawas"
 
ROBERT CROSS's Avatar

 
2003 25' Classic
Zanadude Nebula , WNY
Join Date: Jun 2007
Posts: 11,153
Images: 1
All I really needed was an accurate reading of voltage, and a reliable source for AC status....KISS.

Bob
__________________
PFC.....

“After all these years the reason I continue to love Thanksgiving.....I still sit at the kids table.”
RLC

Sandra wanted to go to Cleveland on vacation,
but I’m the Husband, so we went to Cleveland.
RLC
ROBERT CROSS is offline   Reply With Quote
Old 11-15-2011, 04:38 PM   #9
RLS
Rivet Master
 
RLS's Avatar

 
2004 25' Classic
Prescott , Arizona
Join Date: Jul 2008
Posts: 608
I also wanted to use the biggest battery that I could fit in. These are size 29. Had to use the Dremal and do some "custom alterations" to the bottom frame for them to fit. The bad part of doing this is getting them out! I had to make a shim that goes under the front battery lip at the bottom to catch on to and then pry it up and pull out at the same time.
Attached Thumbnails
Click image for larger version

Name:	IMGP0547.JPG
Views:	90
Size:	338.2 KB
ID:	145280   Click image for larger version

Name:	IMGP0548.JPG
Views:	87
Size:	296.9 KB
ID:	145281  

__________________
Julia & Bob
W/ Deedee & Boo
AIR #30685
RLS is offline   Reply With Quote
Old 11-15-2011, 04:54 PM   #10
CLOUDSPLITTER "Tahawas"
 
ROBERT CROSS's Avatar

 
2003 25' Classic
Zanadude Nebula , WNY
Join Date: Jun 2007
Posts: 11,153
Images: 1
Quote:
Originally Posted by RLS View Post
.... The bad part of doing this is getting them out! I had to make a shim that goes under the front battery lip at the bottom to catch on to and then pry it up and pull out at the same time.
Bob,

It's really hard to tell exactly where your mod's are from the pic. Did you have to notch the frame back a little?

I know the 27 Lifelines are a bear to get out in our 03 Classic....started using one of these plastic scrappers to slide it over the d@mn hinge...may be a little easier for me as they do have a handle on the end.

Bob
Attached Images
 
__________________
PFC.....

“After all these years the reason I continue to love Thanksgiving.....I still sit at the kids table.”
RLC

Sandra wanted to go to Cleveland on vacation,
but I’m the Husband, so we went to Cleveland.
RLC
ROBERT CROSS is offline   Reply With Quote
Old 11-15-2011, 05:02 PM   #11
Rivet Master
 
Silver Goose's Avatar
 
2008 27' Classic FB
Burkburnett , Texas
Join Date: Jul 2010
Posts: 955
I found this meter available for around $25. It comes with a lighter plug so you can simply plug it into the 12v socket on your tv antenna amplifier box if you have one. It doesn't take much to hard wire it to an unswitched 12v line if desired. It also has a user adjustable alarm if you want an alert when the voltage drops to a specific level.

Interstate publishes a spec chart found here:

https://www.interstatebatteries.com/...RVDeepCycle|3|

As you can see, there are some model differences within a given group size. Don't expect to see a spectacular difference in useful battery time going from a 24 to a 27. Airstream could do us a favor by providing battery boxes that could accommodate a pair of 6v golf cart batteries. A pair of them in series will provide noticeably more run time than a pair of Group 27s in parallel.
Attached Thumbnails
Click image for larger version

Name:	image-2580353009.png
Views:	80
Size:	288.0 KB
ID:	145282  
__________________
AIR 47751
Air Safe Hitch, Reese Dual Cam 800#, Centramatics
Silver Goose is offline   Reply With Quote
Old 11-15-2011, 05:57 PM   #12
Rivet Master
 
dznf0g's Avatar

 
2007 30' Classic
Oswego , Illinois
Join Date: Jul 2010
Posts: 9,408
Images: 5
Quote:
Originally Posted by RLS
I also wanted to use the biggest battery that I could fit in. These are size 29. Had to use the Dremal and do some "custom alterations" to the bottom frame for them to fit. The bad part of doing this is getting them out! I had to make a shim that goes under the front battery lip at the bottom to catch on to and then pry it up and pull out at the same time.
Me too, like I said they BARELY fit. I just slip a piece of a 2 liter coke bottle under each for a "slide". But they are 30 more amp/hours each bigger than the group 27s, so I think it's worth the hassle. I also installed a nylon strap around the batts so I can pull them out.
__________________
-Rich-

"If the women don't find you handsome, they should at least find you handy." - Red Green
dznf0g is offline   Reply With Quote
Old 11-15-2011, 08:56 PM   #13
3 Rivet Member
 
2000 25' Excella
Northern , California
Join Date: Nov 2011
Posts: 190
I agree, the 27’s are already a snug fit in the Classics, and taking on an additional ½” in height with the 29’s brings that positive terminal awfully close to the compartment frame on the way out. Any issues?

__________________
Kamiak is offline   Reply With Quote
Old 11-15-2011, 08:57 PM   #14
Road Geezer
 
Road Geezer's Avatar
 
2011 27' FB Flying Cloud
San Jose , California
Join Date: Jan 2011
Posts: 268
Images: 34
Blog Entries: 20
Gene, the battery box mod you described is exactly what I'm planning to do. I already7 have a SawsAll, so I'll pop for a couple metal-cutting blades and have at it. The box is big enough for two grp 27s; as you already know, it's getting the battery in and out over the flange that's the problem. I think I only have to remove one flange.

Stay tuned, I'll post a pic of my results when I do the job in a couple weeks.
__________________

__________________
As far as I know, this is the oldest I've ever been.
Road Geezer is offline   Reply With Quote
Reply


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
Motorhomes, and Charging Batteries.... Keyair General Motorhome Topics 18 10-15-2011 09:21 AM
Yikes! My Fantastic Fans Killed My Batteries Alumaholic Batteries, Univolts, Converters & Inverters 20 10-08-2011 09:33 AM
Bad Batteries? Nightwatch Electrical - Systems, Generators, Batteries & Solar 8 05-23-2011 02:58 PM
Controller wiring to bus bar or batteries? txstreamer Generators & Solar Power 4 04-26-2011 07:10 AM
Batteries lost water/electrolyte blickcd Batteries, Univolts, Converters & Inverters 13 03-28-2011 09:26 AM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 04:09 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.