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Anyone using a Dc to Dc charger for a second battery?

SelfmodJT

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Juat curious if anyone has this setup? Any issues because of the smart alternator or issues with the ESS?
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You mean a third battery? There's two already............... the main battery and then the aux for the electronics when the engine is down.
 

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It's late, the cats are even sleeping..........
 

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SelfmodJT

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Thought i would go this route instead of a battery isolater. Any thoughts shadow?
 

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Lol, you know what i mean.
:scratches head

Thought i would go this route instead of a battery isolater. Any thoughts shadow?
So you want to take a 12V battery, stuff in a DC-to-DC converter, and use it to charge another 12V battery?
That's REALLY inefficient.
What's wrong with an isolator, or even just use a couple of diodes?

Kevin
 
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SelfmodJT

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What's wrong with using a dc to dc charger for second, I mean third battery in the bed to take the load off the alternator? I dont have the upgraded alternator. How is that inefficient? And if I want to add solar panels down the road it seems like the better route.
 
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SelfmodJT

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:scratches head


So you want to take a 12V battery, stuff in a DC-to-DC converter, and use it to charge another 12V battery?
That's REALLY inefficient.
What's wrong with an isolator, or even just use a couple of diodes?

Kevin
Any what is a dc to dc convertor? Please explain mr electrical engineer.
 

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Juat curious if anyone has this setup? Any issues because of the smart alternator or issues with the ESS?
Actually a common and contemporary setup for those running a fridge, lights, air, water and other RV like DC loads. Here is the setup I am building but I went with and SOK LiFePO instead of the cheaper Amperetime as depicted. I have a Renogy DC to DC because it has dual inputs and accommodates the Gladiator's smart alternator.

I have heard there are folks out there that have smoked their smart alternator not realizing it is smart and LiFePO's can suck some serious amperes on charge.

PS. Extremely efficient but not designed as third starter battery. This setup 'saves' your starter batteries for starting.

Jeep Gladiator Anyone using a Dc to Dc charger for a second battery? 1630475874674
 

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SelfmodJT

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Actually a common and contemporary setup for those running a fridge, lights, air, water and other RV like DC loads. Here is the setup I am building but I went with and SOK LiFePO instead of the cheaper Amperetime as depicted. I have a Renogy DC to DC because it has dual inputs and accommodates the Gladiator's smart alternator.

I have heard there are folks out there that have smoked their smart alternator not realizing it is smart and LiFePO's can suck some serious amperes on charge.

PS. Extremely efficient but not designed as third starter battery. This setup 'saves' your starter batteries for starting.

Jeep Gladiator Anyone using a Dc to Dc charger for a second battery? 1630475874674
So I did some research on that charger, what is the best connection for that blue wire for ignition that senses the voltage? Getting different answers.
 

bsteg7

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So I did some research on that charger, what is the best connection for that blue wire for ignition that senses the voltage? Getting different answers.
Mine is still in the box, just got my battery yesterday. Not sure what you mean by blue wire. The IGN lead is red with a green connector. The manual simply states connect the IGN to an ignition source. I will probably connect mine to the ignition lead from the factory 4 aux switch option but any lead that is hot when the ignition is on should work fine.

It doesn't say it senses voltage. I think it simply tells the unit the ignition is 'on'. This is probably because the smart alternator often drops charging to low voltage near 12v under acceleration and therefor the Renogy unit would not be able to tell if the car is on or not. You don't use the IGN lead with a traditional 'dumb' alternator because its obvious to the unit the engine is started because the voltage jumps from 12v to 14v.
 
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SelfmodJT

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Mine is still in the box, just got my battery yesterday. Not sure what you mean by blue wire. The IGN lead is red with a green connector. The manual simply states connect the IGN to an ignition source. I will probably connect mine to the ignition lead from the factory 4 aux switch option but any lead that is hot when the ignition is on should work fine.

It doesn't say it senses voltage. I think it simply tells the unit the ignition is 'on'. This is probably because the smart alternator often drops charging to low voltage near 12v under acceleration and therefor the Renogy unit would not be able to tell if the car is on or not. You don't use the IGN lead with a traditional 'dumb' alternator because its obvious to the unit the engine is started because the voltage jumps from 12v to 14v.
Ok, for some reason on article I read said to connect to the actual ignition circuit? Someone used the cigarette lighter wire and it didnt work right for some reason? Maybe cause it an accessory wire and it shows power even when the car is off in the run position?
 
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SelfmodJT

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I guess using a switch is the best option.
 

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Well I've started with wiring that system (Renogy Dual Input DC-DC 30A) in mine to charge the LiPo battery to run my fridge freezer and other stuff, right now it's just powering my radio. I've not hooked it in to Jeep electric system yet. It would have been done a few days back but I've been tied up with some other problems as of late.
A big thanks to "Dan G. Of the road chose me" who is a member here. I was about to install a different company solar charge controller MPPT type. "It will be going into my RV now"
The trigger wire needs to be hooked to a engine running circuit only it's recommended to not be the 12 v power port due to being on in acc mode too. As you have found out. I'm thinking about trying to use the 5th wire from Aux switch group in cab as a test to save me from needing to run another wire up to engine compartment.
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