Hello! I have an EASUN SMW 8KW inverter with 2 strings East and West orientation and 10KWh AGM battery. My question is, is it possible to charge EASUN batteries with a separate MPPT charger and South facing string? I would like to ask your opinion on this.

4 minutes ago, Hanks77 said:

Hello! I have an EASUN SMW 8KW inverter with 2 strings East and West orientation and 10KWh AGM battery. My question is, is it possible to charge EASUN batteries with a separate MPPT charger and South facing string? I would like to ask your opinion on this.

Yes you can. 

Are you in the southern hemisphere? 

I am in Hungary, here the South orientation is the most ideal for solar panels. My two main strings are east and west facing because that's how I could manage it, I just want an extra string for low sun in winter to have more power in winter.

15 minutes ago, Hanks77 said:

I am in Hungary, here the South orientation is the most ideal for solar panels. My two main strings are east and west facing because that's how I could manage it, I just want an extra string for low sun in winter to have more power in winter.

If you buy a MPPT like Victron(expensive) Epever (reasonable) make sure it can support lithium settings as your next battery bank might be lithiums. Lead acid do not last long with daily cycling. 

You just key in the correct charge/dischsrge settings and connect this MPPT directly to the battery. 

Both makes have the model named on a Voc maximum for the series input and then the 2nd value is the charge rate to the battery. 

Good afternoon @Hanks77 and welcome to the forum.

I did not know the inverter that you mentioned so I googled and had a quick look and I see that the inverter is similar to the 7.2kW / 8kW Axpert Max and Kodak Max which have a dual 4kW 500Voc 18A solar inputs and I have the following questions:

A] What is the amount of solar panels, power rating and the Voc of the east facing solar panel array?

B] What is the amount of solar panels, power rating and the Voc of the west facing solar panel array?

C] Is it possible to post a photo or two from google earth that shows the roof of the property where you indicate where the new panels are going to be installed?

Kind Regards

GerhardK83

20 minutes ago, GerhardK83 said:

Good afternoon @Hanks77 and welcome to the forum.

I did not know the inverter that you mentioned so I googled and had a quick look and I see that the inverter is similar to the 7.2kW / 8kW Axpert Max and Kodak Max which have a dual 4kW 500Voc 18A solar inputs and I have the following questions:

A] What is the amount of solar panels, power rating and the Voc of the east facing solar panel array?

B] What is the amount of solar panels, power rating and the Voc of the west facing solar panel array?

C] Is it possible to post a photo or two from google earth that shows the roof of the property where you indicate where the new panels are going to be installed?

Kind Regards

GerhardK83

Welcome and thank you for your reply! I have 10pcs Canadian Solar 455W panels on the east side and also 10pcs on the west side on the roof. 10x41.2Voc is approximately 410Voc per string voltage. The two strings are connected to 2 different MPPT inputs on the inverter. The new panels are rotated 90 degrees to the south on another rooftop. My original question was whether I could connect an extra MPPT charger in parallel with the inverter 48v batteries, which would charge the inverter batteries from the South string. I cannot post a picture of the roof at the moment.

27 minutes ago, Hanks77 said:

Welcome and thank you for your reply! I have 10pcs Canadian Solar 455W panels on the east side and also 10pcs on the west side on the roof. 10x41.2Voc is approximately 410Voc per string voltage. The two strings are connected to 2 different MPPT inputs on the inverter. The new panels are rotated 90 degrees to the south on another rooftop. My original question was whether I could connect an extra MPPT charger in parallel with the inverter 48v batteries, which would charge the inverter batteries from the South string. I cannot post a picture of the roof at the moment.

Using this Epever MPPT you can connect 3 panels in series and be below the Voc level. 

It can charge at up to 50A for a 2500W charging power to your batteries. 

You can also use the 30 or 40A Epever. The great thing about the same Epever MPPTs is you can add up to 6 in parallel as long as you load the same battery settings to each one. This makes it very scalable. 

https://shop.thesunpays.co.za/products/epever-tracer-an-solar-charge-controller-50a-mppt

Edited December 24, 20232 yr by Scorp007

22 minutes ago, Scorp007 said:

Using this Epever MPPT you can connect 3 panels in series and be below the Voc level. 

It can charge at up to 50A for a 2500W charging power to your batteries. 

You can also use the 30 or 40A Epever. The great thing about the same Epever MPPTs is you can add up to 6 in parallel as long as you load the same battery settings to each one. This makes it very scalable. 

https://shop.thesunpays.co.za/products/epever-tracer-an-solar-charge-controller-50a-mppt

Ok. Thank you!

@Hanks77 I have a 5kW Axpert inverter with 3 x 3000 Pylontech batteries. I have 2 30Amp Epever mpptś conneted in parallel on the battery busbar. The system is running for 18 months with good results.The Epever mppt can be connected to your PC to do settings to match the BMS of the Pylontechs.

 

5 hours ago, Hanks77 said:

I have 10pcs Canadian Solar 455W panels on the east side and also 10pcs on the west side on the roof. 10x41.2Voc is approximately 410Voc per string voltage. The two strings are connected to 2 different MPPT inputs on the inverter. The new panels are rotated 90 degrees to the south on another rooftop. My original question was whether I could connect an extra MPPT charger in parallel with the inverter 48v batteries, which would charge the inverter batteries from the South string. I cannot post a picture of the roof at the moment.

Thanks for the answer, ok the reason why I asked how many solar panels you have is because some of the users of the installed solar system does not understand that there is a power limit on the solar input and that the installed panels are below the input limit because the installer of the system did not explain to the user that you can add a couple of solar panels to the system if the need arises.

To me it is clear that your installation is already over the power limit by 13.75% but I do not think that your solar panels generate over the inverter power limit otherwise you would have added a couple of solar panels to the existing strings. You want to utilize a MPPT so that you can add additional solar panels to the MPPT at a different part of your roof in order to generate more power without changing the solar panels already installed.

I found this calculator: https://footprinthero.com/solar-irradiance-calculator with a couple of links to other calculators where the optimal angles can be calculated according to the address provided for optimal solar power production in case that you want to make the angles of the new solar panels adjustable or optimize the angle of the new solar panels so that it favors a certain season.

When using Epver mppt there is a rated power and a max power. This can make a big difference on the amount of panels to be installed. Up to 50% exceeding the rated power.

 

 

Edited December 25, 20232 yr by Chris Louw

On 2023/12/24 at 4:52 PM, Chris Louw said:

@Hanks77 I have a 5kW Axpert inverter with 3 x 3000 Pylontech batteries. I have 2 30Amp Epever mpptś conneted in parallel on the battery busbar. The system is running for 18 months with good results.The Epever mppt can be connected to your PC to do settings to match the BMS of the Pylontechs.

 

Could you please share some pics of your setup if you don't mind?

The Axpert was installed 2015 and still growing.