SMR-MPPT1575 is a sort of tracer MPPT solar controller. This sort of tracer solar charge controller is fit for 12V/24V automatic recognition as well as 15A charge and discharge current. How to choose solar charge controllers? For PV systems, there are divided into on-grid and off-grid systems....Send Inquiry
SMR-MPPT1575 is a sort of tracer MPPT solar controller.
This sort of tracer solar charge controller is fit for 12V/24V automatic recognition as well as 15A charge and discharge current.
How to choose solar charge controllers?
For PV systems, there are divided into on-grid and off-grid systems. As the name suggests that “on-grid” systems are connected with electrical grid, the PV panels generate DC current, through inverters, input AC current into the electrical grid. Normally on-grid systems are very big. “off-grid” means the solar systems separate from electrical grid, or there is no electrical grid at all. So the PV panels generate DC current, through solar charge controllers, charging the energy into the battery, (lead acid battery or lithium battery). Then battery will provide energy to the load, like lamps, fans, freezers… Solar charge controller is just like the heart of the off-grid systems. But how to choose solar controllers is very important for off-grid systems? Let us introduce to you.
Normally there are 3 kinds of panels, applied in off-grid systems.
First is 36 pcs cells, the panel working voltage at 18V, can be applied in 12V battery. Then you can choose 12V solar controllers. The rated current of PWM solar controller must be bigger than Imp of PV panel. For MPPT controllers, like 10A 12V, only can connect with 130W PV panel, Imp is only around 7.3A. And 10A 24V MPPT can connect with 260W panel. If the PV panel Imp is bigger than the rated current of solar controllers, maybe it will damage the controllers. But some controllers have over current limit protection function, then that is good. But it also means some energy wasted when the charging current exceeds the rated current.
Second is 72 pcs cells, the panel working voltage is at 36V, can be applied in 24V battery. Then you can choose 24V solar controllers. You can choose PWM solar controller according to the above methods. Also you can choose suitable MPPT, like in 12V battery, 10A—130W, 20A—260W, 30A—390W; in 24V battery, 10A—260W, 20A—520W, 30A—780W…
Third, the panels are 60 cells, these panels are mostly applied in on-grid systems. But they can be applied in off-grid systems, only you choose MPPT controllers. The most important is that you must notice the rated input voltage of controller must be higher than panel open circuit voltage. For 60 cells panels, the power is from 250-280W, so you can choose 20-30A MPPT controllers in 12V battery systems.
Normally you must leave about 25% free safety capacity for the solar controller, which is very important.
Anyhow, how to choose solar charge controller, it is very professional, you need to consult with technical engineers from manufacturer.
If you have any request for solar home system controllers, pls refer to the website: www.lumiax.com, to find suitable products.