2 solar chargers in parallel

geogr Registered Users Posts: 6
Regards to everyone in this very educational forum,

My question is the following:

I have a 24V off grid system and 6 PV modules of 80W = 480W
There is already a Steca tarom charger 45A and a relatively large battery system of 12 2V PzS 460Ah.

I would like to add more PV power to this system adding 2 X 230W Solar panels in series using a second solar charger of Phocos MPPT 20.

What are the limitation adding in parallel different solar chargers with different kind of solar panels?

My guess is that there is no problem doing that since both chargers sense a lower battery voltage than the one they can deliver and thus meaning flow of electricity.

However I would like to have a second opinion before I apply my thoughts in practice...

Thanks in advance Giorgos, Greece


  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: 2 solar chargers in parallel

    Charging one battery bank with multiple PV/charge controllers is not a problem. The worst you'd experience would be the usual 'unable to harvest all the potential power' scenario that all PV systems suffer from. In other words, once the batteries are fully charged you have a lot of power potential going nowhere.

    Multiple charge controllers will not interfere with each other; they just adjust according to how they interpret the battery's state of charge as influenced by the other controllers. You can mix MPPT and PWM units too. You can also charge from PV and a generator powered battery charger at the same time.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: 2 solar chargers in parallel

    you will be fine and the extra pvs are needed as it seems you were undercharging your batteries. your about doubling the pv capacity and that puts you near 6% which is good if the pvs are able to replace all of the power that was used.
  • Photowhit
    Photowhit Solar Expert Posts: 6,003 ✭✭✭✭✭
    Re: 2 solar chargers in parallel

    Some simple charge controlers have an over voltage prtection, that might be triggered during an equalizing charge. I think my first ASC controller had this feature.

    Edit - Well I wrote this and it's what I recall, but doesn't make any sense...lol
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.