No expert at all here, but...wouldn't the current rating just refer to the maximum the device COULD do, not what it actually throughputs all the time? I'm not understanding why the alternator would need to keep up?
I guess I'd expect an intelligent charger like that (basically an external BMS unless I'm wrong) would recognize the lower current needs of a lower capacity battery and adjust accordingly.
From my understanding of the Renogy dc-dc charger is that the unit utilizes max amp throughput to charge the aux battery. It has a 3 stage charging profile. If the aux battery is lower than (guessing) 80% or roughly 12.4V, it uses maximum charge. Within 10%-20% of full charge it uses a different charging profile, trickle charge. The last 10% uses a float charge to maintain and optimizes the battery.
With that said, the majority of the time when you're overlanding with a fridge, lights, etc... staying the aux battery overnight or several nights as soon as you start the truck it would try to use the maximum current (20A, 40A, or 60A) to charge. That's assuming the aux battery is below 12.4V.
Technically, your starting battery can have a 12.0V or above and it'll attempt to charge. The smart alternator and bms can only detect amp draws and provide the proper output in amperage to provide enough power. For instance, if my starting battery is above 80% my alternator my simply throttle at 12.0V-12.5V, but pump out 10A to keep the truck and accessories running.
Search the threads for charging issues. Here's 2 threads that I could think of.
Any LR techs on here, or anyone else ever figured a way to bypass or defeat the "smart" charging strategy these trucks use? I came across a report from a supposed LR engineer at one point that stated that the armored versions that LR produces do not have this "benefit". I would assume that...
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Ok, I've been battling battery issues for quite some time. If you don't know, I'm on my 4th battery. This time I got a Duracell Platinum AGM H8 850CCA 92Ah. I decided to change the battery type with my IIDTool in the CCF settings under Body Control and Battery type. I seriously tried all of...
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