My Solar Panel System of 2940 Wp

Posted by Harm Otten in Solar energy 9 Comments»

20090430-zonnepanelen_On April 29’th 2009, finally my solar panels are installed! 14 panels of 210 Wp (Watt Peak) each (Suntech STP210-18/Ub). In total 2940 Wp (Watt Peak). Not a small one. Especially if I tell you that my last year’s usage in electricity has been around 1600 kWh. That’s why I bought it also for the future. If I had an addition to the family, and an electric car! My choices: Hybrid plug-in, or pure electrical, depending on what models will be available. But I will write an article about that some other time. Now more about this installation…

The roof has a slope of about 35°, and is pointed south-south-west (approximately 220°). 15 panels just didn’t fit because of the outlet pipe of the heating, and a bigger inverter would be needed. That’s why it is 14. But in the future I can still use the lower part of the roof.


More than a year ago I took the first step in obtaining a pv-installation. The most (waiting) time took the subsidy settlement of SenterNovem. Keep in mind that this is the settlement of 2008. The new one in 2009 is a bit better. You need to fill in the form digitally, and it will be validated immediately. The costs for the CertiQ subscription will be compensated for, even with retroactive effect for 2008! But it remains a lot of bureaucratic paperwork. So you have to go through it all to get it done. Finally I have a subsidy arrangement for the amount of 2000 Wp. That means, until now I haven’t gotten any money yet, but the last papers are on its way. The 2000 Wp is the power I requested originally, not knowing the installation would be much bigger in the end. But during the request period you can not change it anymore. That is the “Stimulating” effect of the SDE (Dutch subsidy on renewable power generation). So far, it has only slowed me down. I arranged the subsidy settlement myself, but for the expansion of the meter cupboard, and the installation of the panels I hired a company (VLS-Energie). From that I only have to bargain once. After that, someone from Enexis installed the new electricity meters.

The Electricity Meters

The picture on the left shows the old meter in the meter cupboard, on the right you see the 2 new digital ones. Old meter in cupboardnew digital meters Personally I like the old meter, because it’s very satisfying to read it. From the speed of it you can see very nicely how much juice is consumed or produced. On the digital meter, only a small LED blinks once in a while and a small arrow is displayed. When you look at the new meters, the left one is the Gross production meter (necessary for the subsidy), and the right one is the main meter. They are identical and both have 4 counters. 2 for using electricity, low and high tariff, and 2 for delivering electricity back to the net. In the Gross production meter only 1 counter is used.

The inverter

As you can see, I already had an empty pvc-tube which ends up on the attic. So it was only a matter of getting the wires through it, and connect them. On the next picture you can see the inverter.Mastervolt Sunmaster XS3200 Inverter It is the Mastervolt Sunmaster XS3200. It has an integrated display on which you can read the most important values. I use the grey cable (RS-485) on the right, to read the data of the last 30 days with a small laptop and create graphics of them on the computer. I don’t use the standard software from Mastervolt, because it falls short badly. I unravelled the communication protocol, and wrote a small program myself. Inside of the inverter there is a fan, which will run faster in proportion with the produced power. Not suitable to install in a bedroom, unless you like to be awakened up by the “sound of the sun” every morning ;-). Below the inverter there is an extra switch to cut the power. Despite the fact that the inverter will switch of automatically when there is a power cut, it is mandatory. At the bottom of the inverter there is another switch to disconnect the solar panels. These are connected with the red and black connectors in the middle. It all works automatically, so you don’t have to do anything. At night it will switch of automatically, and when there is sufficient light, it will switch on again.

Energy Supplier

In march I changed from energy supplier and went to GreenChoice. Compared to other suppliers, this one has a number of advantages, and in most cases it is even cheaper too! Look, I am not involved in this company or whatever, but I don’t see why you shouldn’t change to it. Only advantages, and you get real clean power. Or you deliver it yourself when the sun shines ☺.

The results

All in all I’m really satisfied with my pv-installation. In the month of May, I had a profit of 384 kWh, and June was even a tiny bit better. My expectation for this year is a profit of approximately 2500 kWh. So, until I own an electric car, I will definitely be a producer of power. I am already looking forward to this year’s final bill of my supplier, or in my case “client” ;-).

9 replies on “My Solar Panel System of 2940 Wp”

am an installation thecnician on out door solar lighting i have saw some of your project pictures and your indoors installation pictures.i want to know more about your indoor installation.i also whant to make enquiering on your solar panels,led lights,poles and battries and the boxes.I would like to be getting supplies from your company and your product.PV solar panels is what i need,ranging from 130-440watts and lihgt LED lights 45-150watts,Low Pressure Sodium (LPS)36-46watt,High Pressure Sodium (HPS)66watts and above. All this should be along with mountin arms and full couplling component including harness. Poles ranging from 5meter to 8meters gervernise stainless or any.If you can get it and their prices,i will be glad getting those items from you in short while,ther is a project for me that this items can be use for.I will be glad for your urgent respons.Thanks… Emmanuel.O.Agbukor

Looking to try it out but is it really easy to set it up? And yes I agree with you we should always try everything to save our lovely environment.

I have a Sunmaster XS3200 and i try to deassembling the Mastervolt Qs Data Control for understand the comunication protocol e write my own software…with poor results! Can you give me some information about the comunication protocol or the small program that you have wrote?


I found your post interesting. I’m leaving in France near to Toulouse and I had a working PV installation of 3 Kwc since August 2010. I’m also interested to have some information about the XS3200 communication protocol in order to try to write my own software. I deeply appreciate if you can help me.
With all my best.

I´m also trying to read data from a XS 3200. Managed to read my parents soladin inverter, but having problems with this one, can you give me some info on the protocol? Thanks!!!

Hi, I’m also really interested about a way to log the data in my MySql database. Can you tell me more about the XS3200 sw you wrote to read data from it? I will be really happy to receive your help!
Best regards,

Relates to the “RS485 / XS3200 Sunmaster communication protocol”, if someone else have some info, his contribution will be appreciate! Thanks!.

I have seen your website and I also would like to get some info on the XS3200 protocol. Any help will be really appreciated.


If you can provide any information how to read the Mastervolt RS485 protocol it would be really great.

Thanks in advance

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