RV.Net Open Roads Forum: General RVing Issues: DC to DC charger

RV Blog

  |  

RV Sales

  |  

Campgrounds

  |  

RV Parks

  |  

RV Club

  |  

RV Buyers Guide

  |  

Roadside Assistance

  |  

Extended Service Plan

  |  

RV Travel Assistance

  |  

RV Credit Card

  |  

RV Loans

Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in General RVing Issues

Open Roads Forum  >  General RVing Issues

 > DC to DC charger

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Sponsored By:
blaczero

USA

Full Member

Joined: 10/16/2020

View Profile


Offline
Posted: 09/11/21 06:21am Link  |  Quote  |  Print  |  Notify Moderator

hey all, I am thinking of putting a 30a charger in my truck to charge the LiFePO4 batteries in my rig.

Is there any kind of formula about how many amps the charger can be by how much your alternator produces? I have a 270a alternator so thinking I'll be more than fine.

AlcoholFreeRV

Rocky Mountain High

New Member

Joined: 09/11/2021

View Profile


Offline
Posted: 09/11/21 06:39am Link  |  Quote  |  Print  |  Notify Moderator

I have a DC-DC charger in my RV to charge from the truck. It's connected to the battery, not the alternator. the max draw from the battery is 150% of the charger capacity (ours is 60 charger, so 90 at the battery. We have dual truck betteries and like 397A alternator in F350 Super Duty) I cant tell you for certain you'd be fine, but I certainly would feel comfortable installing a 30A charger with a 270A alternator

NRALIFR

Truck Camping Out West

Senior Member

Joined: 11/27/2005

View Profile



Posted: 09/11/21 07:31am Link  |  Quote  |  Print  |  Notify Moderator

You’ll be fine. The DC.DC charger can pull as much as 50% more than it’s rated output. Size the input cables according to the mfgr’s recommendation for the length of the circuit.

The charger should be placed as close as possible to the battery it’s charging, not the truck starting battery.

[emoticon][emoticon]


2001 Lance 1121 on a 2016 F450 ‘Scuse me while I whinge.
And for all you Scooby-Doo and Yosemite Sam types………..Let’s Go Brandon!!!


theoldwizard1

SE MI

Senior Member

Joined: 09/07/2010

View Profile


Offline
Posted: 09/11/21 08:40am Link  |  Quote  |  Print  |  Notify Moderator

The charger should be a close to the batteries as possible. If you are connecting to the 7 way trailer harness those are usually fused for 40A - 50Awhich is fine. No need to over size that wire.

S Davis

Western WA

Senior Member

Joined: 08/11/2005

View Profile


Offline
Posted: 09/11/21 11:22am Link  |  Quote  |  Print  |  Notify Moderator

I have a 50 amp on my 2019 Chevy with a 270 amp alternator charging four Trojan T-105s and have had no issues.

Tom/Barb

Oak Harbor, Wa

Senior Member

Joined: 10/16/2009

View Profile



Good Sam RV Club Member


Posted: 09/11/21 05:33pm Link  |  Quote  |  Print  |  Notify Moderator

WE run a victron 12-12-30 amp DC to DC charger, no problems.


2000 Newmar mountain aire 4081 DP, ISC/350 Allison 6 speed, Wrangler JL toad.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 

Open Roads Forum  >  General RVing Issues

 > DC to DC charger
Search:   Advanced Search

Search only in General RVing Issues


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:




© 2021 CWI, Inc. © 2021 Good Sam Enterprises, LLC. All Rights Reserved.