Thread: Beware Charging Dual Battery in D4.

Thanks Paul,

I had a look at the GSL site. The unit looks good. 25Amp charge rate and ignition controlled so it is not impacted by variable voltage that the D4 seems to have.

One problem however... it has a cooling fan! My RedAcr is mounted under the bonnet.... dust and sometimes water everywhere. I don’t think the GSL unit would last long!

The RedArc is completely sealed. It gets fairly hot at times but this is part of the design. I had a look at the RedArc site tonight and they have just released a new unit. It charges at 40Amps and is also a Solar Panel regulator. It also seems to have an ignition wire in the diagram but I’m not sure if this controls the charging. This is one neat unit. Pricey little sucker though... $670!

http://redarc.com.au/products-and-services/dc-battery-chargers/bcdc1240-dc-battery-charger

Guess I will just stick with what I’ve got as it works well.... I would like it to charge a little faster though based on what Drivesafe was saying.

Lots of good info guys... I love this forum!

Peter

Originally Posted by RoverLander

I would like it to charge a little faster though based on what Drivesafe was saying.

Hi Peter, you are in the perfect position to test out different set up configurations and see which one gives the best results for your requirements.

If you need any help with testing, post away!

Originally Posted by RoverLander

. It charges at 40Amps and is also a Solar Panel regulator. It also seems to have an ignition wire in the diagram but I’m not sure if this controls the charging. This is one neat unit. Pricey little sucker though... $670!

http://redarc.com.au/products-and-services/dc-battery-chargers/bcdc1240-dc-battery-charger

Guess I will just stick with what I’ve got as it works well.... I would like it to charge a little faster though based on what Drivesafe was saying.

Lots of good info guys... I love this forum! Peter

I assume I misunderstand but in reading the pdf on the RedArc website I see a solar cell set up and a wire going going to the vehicle ignition.

I assume there are no solar cells in a typical vehicle setup, but the wire to the ignition and the relay is I suppose to make certain power does not transfer from the starting battery to the fridge battery when the engine is off.

I then got to wondering if I was sitting fat, dumb, and happy in the 3 listening to the radio with the engine not running, would sooner or later, the radio stop and then I also would discover that while the beer in the fridge is nice and cold, that the 3 will not now start?

Originally Posted by RoverLander

Guess I will just stick with what I’ve got as it works well.... I would like it to charge a little faster though

Peter

There may be limits Peter, most battery manufacturers specify a maximum charging rate of 20% of battery capacity. In your case this means 120AH/5 or 24 amps.

Check with your battery supplier, but this is a common maximum charge rate.

Roger on the GSL - definitely not an under-bonnet item!

Rgds,

Paul

Originally Posted by bbyer

I assume I misunderstand but in reading the pdf on the RedArc website I see a solar cell set up and a wire going going to the vehicle ignition.

I assume there are no solar cells in a typical vehicle setup, but the wire to the ignition and the relay is I suppose to make certain power does not transfer from the starting battery to the fridge battery when the engine is off.

I then got to wondering if I was sitting fat, dumb, and happy in the 3 listening to the radio with the engine not running, would sooner or later, the radio stop and then I also would discover that while the beer in the fridge is nice and cold, that the 3 will not now start?

Good point bbyer. They don't say much on their website - it may be ignition controlled, or it may be voltage controlled and the ignition lead is just to disable the solar panels, not to enable the DC-DC convertor. Makes their website not very useful for anyone who wants to understand what they are buying.

Don't know about the D3 but cars I am familiar with have both accessory on and ignition on positions. If this Redarc IS ignition controlled, you could connect to the "ign on" part of the car and use the radio in accessory position.

Cheers,
Paul

Originally Posted by Wilbur

There may be limits Peter, most battery manufacturers specify a maximum charging rate of 20% of battery capacity. In your case this means 120AH/5 or 24 amps.

Check with your battery supplier, but this is NOT a common maximum charge rate.

Wilbur, would you care to supply a list of the “most manufacturers”.

Most batteries used in RV use are still flooded wet cell types and derivatives of same.

As such, MOST batteries in RV use have no restrictions on the amount of charge current applied to them because they are literally self regulate themselves, based on the voltage being applied, not the current being applied.

Spiral wound AGMs like Optima actually tolerate full inrush currents when charging.

It’s only standby type AGMs and similar, that have a charger and discharge current limitation, and even this varies from one battery model and make to another, and the variations can be anything from 20% to 35%.

Taking an educated guess, I would put the number of batteries in RV use that have a flat 20% charge current limitation at about 5%, at best, of the total number of batteries in RV use.

So your statement that “MOST battery manufacturers” is nothing more than another GROSS exaggerations.

Originally Posted by drivesafe

So your statement that “MOST battery manufacturers” is nothing more than another one of your GROSS exaggerations.

Yeah, well I disagree with you, but I did suggest that Peter checks with his battery supplier. Not worth risking the batteries for the sake of a quick phone call or hunt on the web.

Wilbur, I don’t ask whether you agreed or not, I ask would you care to supply a list of these “most manufacturers” as you claimed.