Hi Keith

I assume you are referring to  dc to dc  battery charger

How this will meet your needs is not just a simple yes or no

Factors to be considered are

[1]alternator capacity [amps]

[2]Charger output [amps]

[3]House battery capacity[amphrs]

[4]Your type of camping time

[a]   expected time spent in  one spot with out driving 

expected average daily use of battery power amphrs

 [5]when you do break camp how long do you expect to drive for before next stopover

[6] do you have alternative means of charging 

[7]Are both bus & house system same voltage .[12v or 24v]

Lots of questions, but All need to be considered before anyone can give you a realy satisfactory answer

Peter

hammer wrote:

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Hi keith,

Check out the CMCA web site, also there is a book by Collyn Rivers called Motorhome Electrics lots of info in it about battery set ups.

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 I can endorse that recommendation, it's a very informative book and covers many of the "frequently asked questions" we get on this forum.  It's also available from Jaycar Electronics, there may be a store near you.

CMCA site: https://www.cmca.net.au/secure/TradingItemsNonMembers.htm

Motorhome Books site: http://www.caravanandmotorhomebooks.com/books/index.htm

I'd like to clear the air whether we're talking about an inverter or a battery charger here, they are two quite different devices doing very different tasks.

An inverter is a device that takes the 12v DC from the battery and supplies 240v AC to power devices that normally plug into the power points at home.

A battery charger does what the name implies... it charges batteries (normally) from the household 240v power, however there are now types intended for charging "house" batteries from the vehicle's 12v electrical system and I suspect that's what we are looking at here.

Please don't take this the wrong way, but it is difficult to provide a clear answer to a question if the question itself is not clear.  I mention this as a general comment as it does occur from time to time on this forum.

BobnBev wrote:

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K B, That would be a DC-DC converter..24 to 12 volts. they need to be protected with a "crow bar" its a triack with zenadiod set as the trigger to make it a dead short if the volts go to high.. Think trucks use them to run CBs on 12 volts???

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 I would have thought that the crowbar protection would have been built in and of no concern to the user.  A non-technical person would be unlikely to be familiar with zener diodes, SCRs or triacs and doesn't need to be.

We need K & B to clear the air here... Is the vehicles electrical system 24v or 12v?  Are we talking about a DC to DC battery charger, a DC to DC converter (24v to 12v) or an inverter (12v or 24v DC to 240v AC). Unless we know this we are unable to provide any meaningful help.