3RD battery questions

[Alby]

GeeTee, my experience with a DC-DC charger has been the same as Querty and are happy with the result. If you are happy with the way your system works that is great, no point spending the extra $$$ unnecessarily , the money you save is probably enough for a hefty deposit on a Great Wall

Sorry that was a cheap shot, no malice intended

[Wing]

a smartpass coupled with a ctek dc-dc will make everyone happy.

[enthropy]

That's not a cheap system though.
I've had a a c-tek dc-dc charger sitting in its box for the last 6 months because I can't justify buying a smart pass when the projecta isolator I got with my dual battery tray is doing the job just fine.

Edit: with some fancy wiring would I be able to use my projecta isolator and the dc-dc charger? Is there a voltage sensing relay that is adjustable? Running the projector isolator up to a set point then switching to the c-tek unit could be ideal.


Sent from my GT-I9300T using Tapatalk 2

[Aquaholics]

a smartpass coupled with a ctek dc-dc will make everyone happy.

It's the way I have gone for my duel battery set up.

For running three batteries, if the two auxiliary batteries were the same battery, bought the same time etc etc you could run them in parallel. I see no reason they then wouldn't receive 100% charge through the D250S and Smartpass.

Here is a bit of a demo on how they work.

[Qwerty]

Just Put a DC DC charger before the third battery so it is regulated and there will be less strain on the alternator.

By adding a DC-DC charger in the jack off you won't have the ability to use the vehicle mounted AUX battery in the jack off as the DC-DC charger will isolate the two batteries. You want to be able to charge both the vehicle AUX and the jack Off AUX at the same time. If you ever add solar panels to the jackoff this will also let the trucks AUX battery to be charged from solar which is desirable.

What is rarely mentioned is that a DC-DC charger places a constant load on the alternator whereas a conventional isolator does not.

Umm what is a jackoff? You absolutely will be able to charge the batteries at same time, the alty does the starter, the DC-DC does the auxillary battery. You can bridge them if ever in an emergency (such as accidently running your starter flat while engine was off).

As to load ... a DC-DC charger will in theory place a little longer load on the alternator, becvause its putting more charge into the battery (ie charging it to 100% instead of 70%) ... not sure how this is percieved as an issue?

Once battery is charged and in float (or later stage of absorption mode), it doesn't put jack all load on the alternator.

With that said, the alternator is *always* under some form of load, just running the vehicle will suck between 20 - 40amps being ON (fuel pumps, computers, fans, AC, dashboards, ABS, ESP, headlights, foglights, spotlights, UHF, blah blah blah) ... so the notion of there being a bit longer of a load on alternator is moot. (besides, that's what the alternator is there to do ... service load ... and DC-DC charger is seem as a load device ... exactly as the other items are).

Another benefit of DC-DC is that IF you're having a shortfall in the alternator output (at idle they drop to around half of their peak rating) ... a DC-DC will actually switch itself off (thus meaning you get no charge to AUx battery, but allowing the alty to still dump power into the starter and/or prevent discharge scenario). ... though with that said, if you're having a regular short-fall scenario, then somehting is wrong and you have too much load (whether its 2 batts off the alty and not getting enough charge to them, or a DC-DC scenario with it cutting out ... you will still have a shortfall situation to address).

It all boils down to that for my mind, the starter is the critical battery, it needs priority, and needs to be left alone when engine is off. The Aux battery is there for being cycled a lot.

[Qwerty]

a smartpass coupled with a ctek dc-dc will make everyone happy.

It's the way I have gone for my duel battery set up.

For running three batteries, if the two auxiliary batteries were the same battery, bought the same time etc etc you could run them in parallel. I see no reason they then wouldn't receive 100% charge through the D250S and Smartpass.

Here is a bit of a demo on how they work.

geez that's a step up in the complexity stakes! I like it though ha ha. I just have a "simple" dc-dc scenario that I thought was cool!

Might stick these in for some charging

[Aquaholics]

geez that's a step up in the complexity stakes! I like it though ha ha. I just have a "simple" dc-dc scenario that I thought was cool!

I thought the same but went ahead and bought the set-up. I wired it all up on the bench and ran a few tests to help me understand how it all works (still learning). After seeing how it worked on the bench I installed it in the truck. I have been only running it a few weeks now and haven't had a chance to really test it (drain the second battery) but with the installation of the winch, spotties and lockers in the next month or so it will really get a workout.

[enthropy]

geez that's a step up in the complexity stakes! I like it though ha ha. I just have a "simple" dc-dc scenario that I thought was cool!

I thought the same but went ahead and bought the set-up. I wired it all up on the bench and ran a few tests to help me understand how it all works (still learning). After seeing how it worked on the bench I installed it in the truck. I have been only running it a few weeks now and haven't had a chance to really test it (drain the second battery) but with the installation of the winch, spotties and lockers in the next month or so it will really get a workout.

Mate, do you mind posting a pic of where you've installed your set-up?

[Aquaholics]

I have mounted the unit's behind the rear seat on the passengers side. There are some pics of the install in my build thread but none of the units mounted as they are not 100% finished. Still need to get some heat shrink.

Ben's Build Link.

I would have liked them a lot closer to the batteries but I couldn't find anywhere to put them. Thinking about revisiting this tho due to having to run some heavier cable for the portable compressor to run off the rear Anderson.

Leave it with me for a few days and I will grab some pics.

[Aquaholics]

As requested.

Ctek D250S and Smartpass paired behind rear seat of my dual cab.





Upgraded to 175amp mega fuses due to the current draw of my portable compressor.

[Qwerty]

very neat job! any sort of monitoring / dash readouts ?

[Aquaholics]

Thanks Qwerty, it hasn't come up too bad. I am running a Victron Energy BMV-602s which monitors the voltage of both batteries and detailed monitoring of the service battery. Through a 500amp shunt it records and reports voltage, the rate of charge and discharge in amps, estimated state of charge (%), Ah consumed, approximate time to go and all sorts of other stuff I haven't found a use for. It will also alarm or activate a relay at pre-set values if I required but the Ctek's do that for me already.

[enthropy]

Very nice install mate.
Thanks for the pics.

Sent from my GT-I9300T using Tapatalk 2

[Qwerty]

excellent, i was going to go the more advanced monitoring, but in the end just opted with volt meter ... which does me pretty well as I have it known in my head how long since last charge, what use i've been giving it ... and also given the redarc DC-DC has different voltages for different charge states (ie bulk charges at lower voltages but higher current etc) ... i can pretty much deduce where I'm at from a little knowledge and keeping an eye.

I freaked at one point seeing 13.3v whilst driving on the aux ... then realised she was on float charge ... moments earlier it'd been on 15.1v (the final stages of the absorption stage).

[Rustyau]

nice install Ben!

Just to throw another question out there.....

I'm looking at replacing my aux batt, as i think its RS. I was all for an AGM, but i noticed on one in the shop the other day that "WARRANTY VOID IF INSTALLED UNDER BONNET". That sux because thats where my aux lives, and i have no plans to change its home either. So, what type of deep cycle will be happy in the D4D engine room?

Currently there is a basic red arc isolator controlling the system, but im thinking of installing a ctek D250s and possibly a small solar setup.


Also, in plain english, what purpose does the smartpass serve in conjunction with the D250s?

[pjtaylor03]

Has anyone tried one of thoses newer model ARKpack boxes. I saw one at BCF. Pretty pricey, around $400-$500. I think it has a few 12volt outlets, 150w inverter, anderson plug and a DC DC charger option (only 6 amp though) and a built in 240v charger. All with an LCD display telling you whats going on.

[Double-n]

Hi people, just purchased a 2008 SR5 diesel dual cab and was looking at installing a 2nd battery - ARKPACK in the tub,has anyone had any experience with these, I will be running HD fused cables from main battery to an Anderson plug in the tub and then plug ARKPACK into Anderson. When camping or at home I can remove fridge and Arkpack and run off either solar, mains or genset. Any help or ideas would be appreciated as I am still not 100% sure if this is the right setup, I am only running a 40lt evakool fridge in the tray and a 12v shower and a 12v transfer diesel pump when required to top upthemain tank ( selector brand style diesel tank in the tub).

[mattwhite]

I'm not sure there's a right or wrong answer. I think a lot of people have them under the bonnet for convenience and space. If you can afford the room then great. Do you need a 12v supply at home?

[Double-n]

G'day mat white, def don't have room under bonnet have fitted ARB compressor and a pre filter where 2nd battery would go, don't really need 12v at home but I can plug Arkpack into mains to keep the charge upto the battery -any feedback or ideas are appreciated but I would love to hear from someone who has an Arkpack....

[Skog07]

Bump up for 07luxyTD
Only 62 pages back using the search function..