Top Navigation  
 
U.S. Flag waving
Office Hours Momday - Friday  8 am - 5 pm Pacific 1-800-835-2418
 
Facebook   YouTube   Twitter
 
 
Backwoods Home Magazine, self-reliance, homesteading, off-grid

Features
 Home Page
 Current Issue
 Article Index
 Author Index
 Previous Issues
 Print Display Ads
 Print Classifieds
 Newsletter
 Letters
 Humor
 Free Stuff
 Recipes
 Home Energy

General Store
 Ordering Info
 Subscriptions
 Kindle Subscriptions
 ePublications
 Anthologies
 Books
 Back Issues
 Help Yourself
 All Specials
 Classified Ad

Advertise
 Web Site Ads
 Magazine Ads

BHM Blogs
 Ask Jackie Clay
 Massad Ayoob
 Claire Wolfe
 James Kash
 Where We Live
 Behind The Scenes
 Dave on Twitter
Retired Blogs
 Oliver Del Signore
 David Lee
 Energy Questions
 Bramblestitches

Quick Links
 Home Energy Info
 Jackie Clay
 Ask Jackie Online
 Dave Duffy
 Massad Ayoob
 John Silveira
 Claire Wolfe

Forum / Chat
 Forum/Chat Info
 Enter Forum
 Lost Password

More Features
 Contact Us/
 Change of Address
 Write For BHM
 Meet The Staff
 Meet The Authors
 Disclaimer and
 Privacy Policy


Retired Features
 Country Moments
 Links
 Feedback
 Radio Show


Link to BHM

Get Powered Up! Certified Energy Manager Jeff Yago answers your alternative energy questions

Wondering about a great new energy-saving device
you found on the Internet? Then CLICK HERE!

Sorry. Jeff no longer answers questions online.
This will remain as a searchable
resource for all BHM website visitors.



 

Charge Controllers for Battery Banks

Friday, April 3rd, 2009

Jeff,

I need to use 2 to 4 12VDC batteries in parallel to achieve the necessary amp-hours required for a project.

Will a Morningstar charge controller (Sun Light 10 or Sun Saver 10, for instance) reliably monitor the voltage and charging current of the battery bank as well as it does for a single battery?

Thanks,

Richard Heiser
Sacramento, CA

Richard,

A solar charger is sized based on the following –

First, total short circuit amp rating of solar array X 125% .    Note- Under extreme cold and sunny days, its possible for a solar array to reach 156% of short circuit amp rating for short periods and this is used to size solar array wiring.  If your charge controller does not have this temporary surge capacity, you should use the larger multiplier .

This calculation will determine the “amp” rating of the charge controller.

Next, select voltage for charge controller.  This will be total voltage for battery bank.  For example, two batteries of 12 volts in series would require a 24 volt controller.  Four batteries of 12 volts in parallel would require a 12 volt controller.  Four batteries of 12 volts with 2 in series and 2 in parallel would require a 24 volt controller.

The controller doesn’t know or care how many batteries you have or how they are wired, as long as the controller design voltage matches the voltage of the battery bank.

Now that you know amp rating and voltage for controller, select a model with the options you need, like digital meter, low voltage dis-connect, and/or temperature sensor.

Good luck,

Jeff Yago

 
 


 
 

 
 
 
 
 
Copyright © 1998 - Present by Backwoods Home Magazine. All Rights Reserved.