RFI and solar panel inverters

[VK4WTN]

Just an enquiry if anyone knows which the better inverters to use with solar panels in regards to RF interference.I am looking at getting solar panels installed and the two inverters that I have looked at are Sunnyboy and Delta.Has anyone used either of these and have they had any interference issues?
Any information would be appreciated regards Wayne VK4WTN

[VK3BY]

Wayne
I have a 1.5kw system and have the Sunnyboy SB1700 no problems with it. The first inverter was transformer less and was a qrm generator every 19khz. I also asked around and the replies I got indicated that the Sunnyboy by SMA Technology were ok. Most recommended German made inverters, regards David vk3by.

[VK4WTN]

Thanks for the reply David, always a worry installing something like an inverter never know whats going to happen.By most reports the Sunny Boy is one of the better inverters
regards Wayne VK4WTN

[VK2CBL]

I have just had a 3Kw system installed three weeks ago. I chose a Sunnyboy 4Kw inverter above all the Chinese inverters. I have over 20 years experience in the Switch Mode Power Supply repair business and felt that the German inverter would be far more superior to the Chinese ones. During installation I was able to install ferrite suppressors on both the DC lines and also on the AC lines. After installation I checked QRM on the HF bands and found that I had s9+10db of hash. I was not very happy and then decided to completely shut down the inverter. When the inverter was shut down I noticed that there was no change to the hash. It now appears that this hash is being generated by the solar installation two doors from me.
The two types of ferrites I used were 28-112-38 and M-HEX-SPLIT/F29. Both are available from Neosid 02 9660 4566.

Hope this helps.
Len

[VK4WTN]

Thanks for the response Len, I will organise some ferrites.Which of the two types of ferrite that you mentioned did you use on the DC side and which was on the AC side.Also how many turns did you wind onto the toroid
Thanks for the help regards Wayne VK4WTN

[VK2OT]

Hello Recently my fathers Sunnyroo inverter stopped working .Sunnyroo are now unable to be contacted for warranty purposes.Does any one know how to contact them ,i have tried email and there available phone numbers and no response.The sunnyroo system 8kw 2X 5000 watt inverters does not produce any rfi at this location. Lucky he had them insured so the insurance covered it. mike vk2ot.

[VK2CBL]

Wayne,

I used five of the 28-112-38 F19 Ferrite Tubes on the AC cable leaving the inverter. On each of the DC cables (total of four DC cables used on my system) I used two M-HEX-SPLIT/F19. The tube type ferrites need to be threaded on to the AC cable before completion of installation. However the split ferrites can be attached after the installation.

Hope this is some help. If you need to know anything more then it is best to phone me at my home QTH. The number is listed in the phone book.

Cheers,

Len

[VK4WTN]

Thanks for all of the information Len, Ill set mine up the same way as you have done.It wont be installed for a few weeks yet.Thanks again for all the help
regards Wayne VK4WTN

[VK2FAK]

Hi all.....

Len, you did the best you could on your solar power system......but nobody around you will be doing the same thing...

So where does this leave you......

The question remains though.....can it be simply fixed with some clip on ferrite's.


I have some bad interference on mainly 40m but can assume its on all bands to some degree.......and strangely enough it disappears after sundown.....

Maybe its time the WIA pushed the Fed's to have a serious look into this.....or do we have to wait till a Police station has problems, or an emergency service has issues .....

John

[VK2CBL]

John,

Just try using a heap of the split ferrites from Neosid. P/no M-HEX-SPLIT/F19.

Make sure that you buy twice as many as you need as they are sold as halves.

The specifications are: Z at 25 Mhz is 150 ohms and at 100 MHz its 240 ohms.

They are very easy to install using cable ties.

The fact that the QRM increases during the day and disappears at night is indicative of Solar.

The cheap inverters have very little filtering, especially at the DC i/p stages. This then means that the hash is then radiated via the DC cables going to the panels. Fitting the ferrites as close as possible to the inverter will greatly reduce the noise. Some of these inverters are landed in Australia for less than 250 bucks. By the time it goes thru all the mark-up, it usually will cost more than 1500 bucks or what ever they think they can get away with.

As to the problem with the QRM coming from my neighbours. All I have to do is to wait a couple of years and the crap inverters from China are bound to fail. Then when the customer realises the exorbitant price for a replacement then they will not bother. All will then be quiet again.

[VK2FAK]

HI all....


Len....I don't have solar.......just the result of other people having Solar...


With you adding those Ferrite's but still getting hash from others....how do you know what you have added has any impact.......have you done some testing......because if it is that simple.....the Fed's could make it that all systems have them on installation.....who knows...

Maybe grab a few clip on ones and go to the people 2 houses down and see if they will let you clip them on to there Solar system.........assuming you have some friendly contact with them at all...

You say a couple of years and they will break down.....but the problem is..more people get them, as you have, so the problem could go on for many many years....

John

[VK4BLP]

I've got a SMA SB5000TL here with some 33 panels attached to it, and I have no RFI issues at all with it.

My system is listed at http://pvoutput.org/list.jsp?id=4221&sid=3316&v=0 The gap in the last week was due to the timezone being incorrectly set in the inverter.... doh!