Reply
 
Thread Tools Search this Thread Display Modes
 
Old 09-14-2016, 02:16 PM   #1
3 Rivet Member
 
2016 23' International
Salem , Oregon
Join Date: Nov 2015
Posts: 226
Battery Monitoring what numbers to use

When fully charged says 12.8 V 100% charged. Another time it says 12.2 V and 94.2% charged.

If I read a typical chart it says that 12.2 is 60% charged not 94.2% so what good is the % of charge indication.

I just want to keep the batteries in good condition and fully charged them at 12.2V.

Dave
__________________

__________________
NoResults is offline   Reply With Quote
Old 09-14-2016, 02:25 PM   #2
Rivet Master

 
2014 20' Flying Cloud
Long Island , New York
Join Date: Jun 2015
Posts: 4,147
Not sure if you are getting the Volt and Percentage figures from the same monitor? Ours only shows volts FWIW, so I will comment on this side of the equation. Just one lay person's opinion.

After you charge your batteries, and wait one hour after unplugging shore power, the general rule of thumb is that your monitor should show 12.8 volts plus or minus. The batteries should then hold a charge above 12.5 for 2-3 days, assuming you do not use any 12-volt items.

When the batteries get down to 12.5 volts, they are still holding about 90% charge. When they get down to 12 volts or so, they are then at 50% and you start to do serious damage to them if you use them further without charging. We always try to keep ours above 12.5 volts, as we have a quiet Yamaha tri-fuel 1000 watt generator, which is easy to hook up and run without disturbing the neighbors.

I am on the road right now, but will post reference material and a chart when I get home in an hour or two.

Peter

PS edit -- have not read your other thread yet, but for every one's information:

http://www.airforums.com/forums/f449...ll-155393.html
__________________

__________________
OTRA15 is offline   Reply With Quote
Old 09-14-2016, 02:34 PM   #3
3 Rivet Member
 
2014 25' FB International
Metuchen , New Jersey
Join Date: Sep 2012
Posts: 103
The best investment I made when getting my trailer is the Garmin RV GPS. Highly recommended.
__________________
GenXair is offline   Reply With Quote
Old 09-14-2016, 02:39 PM   #4
Rivet Master
 
BambiTex's Avatar
 
1967 26' Overlander
1955 22' Flying Cloud
1964 17' Bambi II
Clear Lake Shores , Texas
Join Date: Nov 2013
Posts: 1,056
Wrong thread?

Quote:
Originally Posted by GenXair View Post
The best investment I made when getting my trailer is the Garmin RV GPS. Highly recommended.
Perhaps...
__________________
BambiTex is offline   Reply With Quote
Old 09-14-2016, 02:41 PM   #5
Rivet Master

 
2014 20' Flying Cloud
Long Island , New York
Join Date: Jun 2015
Posts: 4,147
GenXair did you mean to post in another thread perhaps?
__________________
OTRA15 is offline   Reply With Quote
Old 09-14-2016, 02:47 PM   #6
3 Rivet Member
 
2016 23' International
Salem , Oregon
Join Date: Nov 2015
Posts: 226
I should of been more clear. I added the Victron Battery monitor which gives
the following info

batt voltage, current (amps) power (watts) consumed amp hours, state of charge time to go (h) estimate of how long battery can support current load till neading charge., batter temp

I thought would gain some valuable information but now I am a little confused.
__________________
NoResults is offline   Reply With Quote
Old 09-14-2016, 03:04 PM   #7
Rivet Master

 
2014 20' Flying Cloud
Long Island , New York
Join Date: Jun 2015
Posts: 4,147
I would recommend going back to the other thread for continuity purposes. I saw some posts by Lewster, the resident expert here, about information overload. We are re-inventing the wheel with Lew on board already on this trailer, in my personal opinion.

Good luck!

Peter

PS -- Edit -- yup here is the post:

Quote:
Originally Posted by lewster View Post
I would add the 702 and even go a step further with the new Color Control Monitor as well. They will give you more information that most can use, but it's great having information overload!
PS2 -- Here are the resources I mentioned earlier -- FWIW for continuity on this thread:

http://www.marxrv.com/12volt/12volt.htm
Voltage table on its own: http://www.marxrv.com/12volt/voltchart1.gif
__________________
OTRA15 is offline   Reply With Quote
Old 09-14-2016, 10:19 PM   #8
Rivet Slave
 
Rocinante's Avatar

 
2014 27' FB International
Western WA , Washington
Join Date: Dec 2013
Posts: 2,901
Blog Entries: 49
One thing for sure...the most reliable measure of your battery voltage is *at* the battery. We have a solar panel that reports voltage, and it's regularly at least 0.2V low. The See Level II monitor seems to vary from being on target to being 0.1V or 0.2V low. So, sometimes we think the battery is lower than it is. So I got out to the tongue and measure it. In fairness, I should also say that we don't have a shunt or a measure of amp hours going in / out of the batteries. I just go out there with a volt meter. Some day...
__________________
Rocinante is our 2014 International Signature 27FB
(Named for John Steinbeck's camper from "Travels With Charley")


Rocinante is offline   Reply With Quote
Old 09-15-2016, 10:24 AM   #9
Zil
3 Rivet Member
 
Vintage Kin Owner
Currently Looking...
egg harbor city , South Jersey
Join Date: Apr 2014
Posts: 195
"I should of been more clear. I added the Victron Battery monitor which gives
the following info....."
The Victron measures amps-in / amps-out to track state of charge. I use the % scale on mine. All the negatives must go through the shunt. Then the meter must be set to the proper specifications for your battery bank.
One way to determine 100% charge is how many amps are the battery accepting at 14.++ volts. Maine Sail has a very good article about this. http://www.marinehowto.com/
__________________
Zil is offline   Reply With Quote
Old 09-15-2016, 10:32 AM   #10
Rivet Master
Commercial Member
 
lewster's Avatar
 
Vintage Kin Owner
Naples, FL , Hood River, OR
Join Date: Dec 2005
Posts: 7,216
Just a quick note about the chart above. This is applicable for many LIQUID CELL batteries but does not apply to many AGMs, especially Lifelines, which are 100% at 12.8-13.2VDC and 50% at 12.2VDC.


Lew Farber
__________________

__________________
Lew Farber...ABYC Certified Master Marine Electrician...RVIA Certified Master Tech ...AM Solar Authorized Installation Center...AIRSTREAM Solar & Electrical Specialist...Micro Air 'Easy Start' Sales and Installations
lewster 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
Micro Plus Monitor - monitoring battery only Northerngirl Plumbing - Systems & Fixtures 2 05-23-2016 10:03 PM
Proper Battery Voltage/Monitoring RICKBETTY Sprinter and B-van Forum 8 03-14-2016 10:51 PM
BM Pro Wireless Battery Monitoring daveswenson Batteries, Univolts, Converters & Inverters 4 01-03-2016 03:10 PM
Monitoring Battery Voltage While Using Equipment KJRitchie Batteries, Univolts, Converters & Inverters 19 06-03-2015 10:28 AM


Virginia Campgrounds

Reviews provided by



Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 08:07 PM.


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.