Can I parallel a 150/100 and a 250/100 smart solar MPPT or do they need to be the same input voltage? Thanks
asked
Mixing MPPTs
Since you mention the input voltage, i assume you want to feed both MPPTs from the same PV string?
I skimmed over the manual for the 250/100, i have not seen that this would be explicitly forbidden.
But i also cant imagine that a config like this would offer a good efficiency. Im imagining both MPPTs hunting for the maximum powerpoint, each influencing the other, and thus not reaching a stable state. Or they let the magic smoke out.
On the battery side, you can use mutliple MPPTs in parallel, the model of MPPT does not matter, so you can use a 150/100 and a 250/100 on the same battery
You cannot share PV, this is EXPRESSLY unsupported. The docs show how units can be paralleled. In no way is there an example that shows shared arrays, and no vendor will create documentation based on detailing everything you should not be doing.
I have lost track of how many similar questions have been answered with this guidance, all available via a simple search.
If you aren't sure, rather don't imply that it could be done.
Each MPPT needs its own string, they can be completely different to any other string on other MPPT's, they just need sufficient voltage to start the charger and to keep it running.
The whole point of multiple MPPT's is to cater for different array sizes, shading etc.
Thanks for the replies. It's 2 x controllers for 2 separate strings - 150/100 will have 3S5P and the 250/100 will have 4S4P, both to the one battery bank.
@johnp It's 2 x controllers for 2 separate strings - 150/100 will have 3S5P and the 250/100 will have 4S4P, both to the one battery bank
That's a better question. GIGO.
Yes, you can have 2 different arrays with 2 seperate mppt's, with each mppt having different input voltages (within the mppt's input limits) charging the same battery bank.
Do make sure the mppt's battery settings are the same.
