4 replies to this topic

[Ruck_and_Roll]

This is a practical and theoretical question.

 

How do multiple charging sources interact?

 

For example,

I just installed the following:

-Renogy 160watt panel with Victron 75/15 charge controller

 

I have Surepower 1314 for DC-DC charging (currently unplugged).  Have plans to install BlueSea 7622 and 4 or 6 awg.

 

What happens when I connect to the truck? Can the battery simultaneously charge from the solar and the DC to DC with the SurePower?

 

Needless to say, I am confused.  

[Norsman]

Hmmmm. My 2019 Hawk front dinette with solar charges the truck battery all the time, mostly when plugged in to shore power.

[PaulT]

As long as you keep the battery chemistry the same in truck and camper, you will minimize any issues. That is, having AGM batteries in both places would likely be ideal.

 

Having LiFePO4 in the camper and lead acid in the truck may present some issues. I have experienced some of these after installing LiFePO4 batteries in the camper. My camper batteries at 13.3 volts appeared to be in a charging state as far as the truck electric system was concerned and tthe AGM battery in the truck at 12.8v or lower was being kept topped off at the expense of the camper batteries being drawn down over time while low solar input was available.

 

The truck battery had a constant draw due to the clocks, computers etc. in the truck. My camper batteries were happy to provide that energy.  Mind you, this may be a good thing if you are trying to keep the LiFePO4 batteries at 80% or lower in storage, but it woulds be imporetant to keep monitoring the situation.

 

I disconnected the truck to camper positive wire to test my theory and the camper batteries stopped being drawn down a little overnight  We each should be aware that there is at least, some interaction between the systems and handle it as we see fit.

 

Paul

[ntsqd]

I want to say that others better versed in this have said that the biggest bully wins and it's not really conflict. If the solar has more power then it does the bulk of the work. If the alternator has more power then it does the bulk of the work.

[Vic Harder]

+1 to what Paul said.  Both AGM is super easy, and:

 

1) Solar will charge both batteries

2) Alternator will charge both batteries

3) Alternator is dumb, Solar is "smart"

4) I have the Blue Sea 7622 with remote disconnect, and monitor the charge state of my camper batteries while driving and disconnect them from the alternator once they are at 90%, and let the Victron MPPT do the final bit of charging with more finesse.