Ready to jump in the solar world

[JimboC]

I have a question for the group. How do you deal with multiple 12 v power sources, I have a WFCO 3785 that puts out 13.5 volts, 7 pin connector wiring from truck putting out 12-13 volts and the MPP2424 sending up to 14+ volts to batteries. The WFCO is not a lithium charger. Right now they are all tied together sending power to the lead acid battery. I have not hooked up the lithium batteries to the wiring harness, waiting to get some advice on this. I had to get a 24 - 12 volt converter that I will connect to the RV wiring harness.
Thanks Again

 

[sunshine_eggo]

Charging from multiple sources

One can have as many independent charging sources running concurrently as they like provided they are programmed properly for the voltage of one's battery bank. Examples (some or all at once, even multiples of a single type, different brands, etc.): Solar PV via MPPT Solar PV via PWM AC-DC...

diysolarforum.com

Since your sources are different, typical behavior is that once the battery has raised above the source voltage, the source just sits there doing nothing UNLESS the voltage raises too high beyond its output. In the vast majority of cases, devices labeled as "chargers" deal with it just fine.

There is no need for a "Lithium" charger. Lithium is essentially a drop in replacement for lead acid. Lithium charges great at 13.8-14.4V and floats fine at 13.5-13.8, but 13.5 is preferable.

The "converter" needs to be a "charger," or you might get unwanted behavior. If it's only putting out 12V, that's not enough for the batteries.

 

[JimboC]

Charging from multiple sources

One can have as many independent charging sources running concurrently as they like provided they are programmed properly for the voltage of one's battery bank. Examples (some or all at once, even multiples of a single type, different brands, etc.): Solar PV via MPPT Solar PV via PWM AC-DC...

diysolarforum.com

Since your sources are different, typical behavior is that once the battery has raised above the source voltage, the source just sits there doing nothing UNLESS the voltage raises too high beyond its output. In the vast majority of cases, devices labeled as "chargers" deal with it just fine.

There is no need for a "Lithium" charger. Lithium is essentially a drop in replacement for lead acid. Lithium charges great at 13.8-14.4V and floats fine at 13.5-13.8, but 13.5 is preferable.

The "converter" needs to be a "charger," or you might get unwanted behavior. If it's only putting out 12V, that's not enough for the batteries.

Thanks for the reply. The converter I bought to supply 12 volts is rated at 40 amps. I disconnected the WFCO converter, no need to have 2 converters doing the same thing. I will put a disconnect on the 40 amp 12v converter when I drive. The truck will put out 12-13 volts, my thought is I can charge as I drive and use the 120 volts to run the Propane/Electric fridge. When I stop I will disconnect the 7 pin, then connect the 40 amp converted 12v to run the trailer 12v system. Now I have the best of everything. Turn a couple of disconnect switches and then I do not have any issues of the power sources. That will also prevent the truck battery from losing its charge if I run the batteries to low.
This might be overblown for some people, just trying to make sure it all works for me.
Thank You

 

[JimboC]

Thanks for the reply. The converter I bought to supply 12 volts is rated at 40 amps. I disconnected the WFCO converter, no need to have 2 converters doing the same thing. I will put a disconnect on the 40 amp 12v converter when I drive. The truck will put out 12-13 volts, my thought is I can charge as I drive and use the 120 volts to run the Propane/Electric fridge. When I stop I will disconnect the 7 pin, then connect the 40 amp converted 12v to run the trailer 12v system. Now I have the best of everything. Turn a couple of disconnect switches and then I do not have any issues of the power sources. That will also prevent the truck battery from losing its charge if I run the batteries to low.
This might be overblown for some people, just trying to make sure it all works for me.
Thank You

The 24 - 12 volt converter will not be charging the batteries, just running the 12 volt trailer needs. The battery charging will be done by solar or plug into chore power.