Reply
 
Thread Tools Search this Thread Display Modes
 
Old 11-29-2010, 04:28 PM   #1
3 Rivet Member

 
2012 30' Classic
Homosassa , Florida
Join Date: Nov 2010
Posts: 218
Battery Tender Hookup for two parallel batteries

I couldn't find this information so I thought I would share what I learned to hookup a Battery Tender to our 2011 25' Flying Cloud that has two batteries. Our previous A/S had only one battery. We wanted to keep the battery on a Battery Tender anytime it was in storage so for anyone interested here is the hookup per Battery Tenders website at Connecting Batteries & Chargers - Batterytender.com





Two Batteries in Parallel, One Charger


Figure 9: Two Batteries in Parallel, One Charger
Batteries connected in series strings can also be recharged by a single charger having the same nominal charging voltage output as the nominal battery pack voltage. In Figure 8, a single 24-volt charger is connected to a 24-volt battery pack.

In Figure 9 we see a pair of 12-volt batteries connected in parallel. This 12-volt battery pack is connected to a single 12-volt charger. Note the blue wire designated W1. The purpose of this wire is to balance the voltage drop evenly across both batteries and each wire during charging. This is not critical for lower current chargers, but when you start to get into the 10 amp and above range, the voltage differential can be significant. The blue wire W1 must be connected to the opposite end of the battery pack as the black wire at the top of the battery pack.

When batteries are connected in parallel, only use one charger. Do not connect a charger to each battery, unless you break the electrical connection between the batteries. The reason is that the chargers will very likely complete one or more their charging subroutines (charge modes or stages) at different times. That means that each charger would be trying to bring the battery pack to a different voltage level. Depending on how the chargers are configured to prevent a reverse polarity connection, the charger with the lower voltage output could possibly draw current from the charger with the higher voltage output, or even from the battery pack that it is trying to charge. If the chargers' reverse polarity protection mechanism includes a solid state, unidirectional, voltage controlled, current switch (like a diode), then this is not a big problem.
__________________
Tater 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
Deltran Battery Tender Jean Wisjink Batteries, Univolts, Converters & Inverters 0 10-13-2010 05:57 PM
Battery tales – upgrading batteries for boondocking Safari SE hshovic Batteries, Univolts, Converters & Inverters 12 04-22-2009 01:50 PM
Which battery (batteries) are connected to solar? Santart Land Yacht/Legacy Motorhomes 1 08-29-2007 05:15 PM
Dual Battery hookup sectionc Electrical - Systems, Generators, Batteries & Solar 9 02-11-2006 01:41 PM
Vintage Bambi battery hookup & DC questions Rosemary Electrical - Systems, Generators, Batteries & Solar 6 12-25-2003 11:11 PM





All times are GMT -6. The time now is 04:57 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.

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