Good day to you all.I am glad to be on this platform.I was invited to check one installation was done using Mecer Sol-i-a-ax-5kp , as an electrician with minimum understanding of solar system.The system from the client point of view was supposed to cut the bill and assist on power outages.I have not yet worked on this type of inverter, when I saw it was very curious to understand how it works and how it can be useful.What I noticed is that the system is showing charging from both solar and utility.From explanation I got, once utility is off, the system will stop charging.The inverter is connected to Pylontech US3000 batteries.The client needs the system to be resolved to cut the bill.My questions are as follows, 1)The installer did not leave the manual for the inverter and softwear disc, how can I access these on line, I checked and only got some almost similar to the model. 2) What is the max number of US3000 batteries can be connected on this inverter. 3) The client wants to access the units online in order to check their performance, how can this be facilitated. 4) I am assuming these units can be connected in parallel, and I wandered why the installer decided to connect them separately. I will be very glad to hear from you experts as the client is keen to expand.

 

Regards

Kulumani

For remote monitoring get Solar Assistant (www.solar-assistant.io)

On 2022/07/30 at 8:30 PM, Kulumani Mangwana said:

one installation was done using Mecer Sol-i-a-ax-5kp ,

This is an Axpert King 5K-48.

On 2022/07/30 at 8:30 PM, Kulumani Mangwana said:

when I saw it was very curious to understand how it works and how it can be useful.

The Kings are different to other models in that they are double conversion; power can be converted from AC (utility or generator) to DC (the "bus") to AC (for loads). So it can switch from battery to utility instantly, and can blend utility and solar power.

On 2022/07/30 at 8:30 PM, Kulumani Mangwana said:

From explanation I got, once utility is off, the system will stop charging.

There is no reason that the battery can't be charging from solar when the utility is off. Of course, if you don't have enough solar, the difference has to come from the battery.

On 2022/07/30 at 8:30 PM, Kulumani Mangwana said:

1)The installer did not leave the manual for the inverter and softwear disc, how can I access these on line,

As posted elsewhere on this forum, the manual is here: https://www.mecerpc.co.za/pdf_downloads/10/102168_PDF2.pdf

The disc only has Watchpower, and very likely an old version of it. Some people think Watchpower is poor, others are happy with it. It can be downloaded from the Voltronic Power website, or slightly easier from here:

https://www.mppsolar.com/v3/download/ and choose your operating system under Monitoring Software.

On 2022/07/30 at 8:30 PM, Kulumani Mangwana said:

2) What is the max number of US3000 batteries can be connected on this inverter.

No real limit. Above about 8 you need a special gizmo, I forget what it's called.

On 2022/07/30 at 8:30 PM, Kulumani Mangwana said:

4) I am assuming these units can be connected in parallel, and I wandered why the installer decided to connect them separately. I will be very glad to hear from you experts as the client is keen to expand.

To parallel them you need one paralleling kit per inverter. These kits connect the inverters to each other via special cables; they talk to each other over these cables. Each inverter should have its own breaker between its AC-out and the load. It's not a trivial thing to set these up correctly, and there is a chance of blowing them up.

It's possible to split the loads and not run them in parallel, but then you have the hassle of running out of capacity on one inverter when the other is lightly loaded. Plus, it's two (or more) systems to configure etc.