I live in Australia. A close neighbour of ours cheaped out and got a dodgy solar system which is emitting all sorts of RF, causing our internet speed to be slowed way down. The difference in speed with neighbor's inverter switched on/off is about 16 times (not joking). We asked that neighbour to turn her solar system off, slow speed issue immediately goes away. We also notice a difference in speed during day/night, since the solar equipment doesn't work during the night it's much faster. As soon as 5am hits when the sun rises, we get heaps of dropouts in the early morning.
Standing outside neighbour's house with an AM radio makes all stations unhearable and just filled with bzzzz sounds. This can be heard in this recording where I walk up to her home
https://instaud.io/2nrf. The government body responsible for dealing with this sort of thing (the ACMA) sent a technician out who identified AM noise from the solar inverter but doesn't think its significant enough to cause AM interference or internet dropouts (despite my tests). They are also a diagnostic service only, it's up to the neighbour to fix the issue. I've contacted my ISP who sent a Telstra technician out. He's known about this
specific solar company installing this dodgy inverter for years to heaps of other customers and he basically said he or our service provider can't do anything until NBN comes, then it's NBN's problem. This isn't an isolated situation as other people with these same model inverters from the same company are having identical issues. I have tried turning off the power at my powerbox and battery powering (DC) the modem with a laptop. With literally every single circuit breaker switched off at my circuit board, the issue remains, so I don't think it would be conducted through the mains cables if battery powering the modem gives identical symptoms.
More detailed pictures of the install:
https://imgur.com/a/1M5qS - The SDS3KW belongs to my neighbor, and the SDS4KW is
somebody a few streets away with the identical problem.Photo I found on facebook of a failed install, posted in January 2018. Seems like DC isolator was incorrect and melted. The solar installers are identical for all of these pictures.
Awesome guy sent me these pictures of his install of identical model, look slightly different. Pretty sure he was a sparkie but he said the capacitors on the inside had failed and there was oil inside the inverter. Solar company refused to warrant his product and ignored communication until he got the electrical safety officer involved.
Inverter model is a Sandi SDS3KW (company also gave out SDS4KW, the chinese manufacturer is now out of business). The neighbour is a lovely older lady, which she has been extremely cooperative. Her system is still under warranty so when she got it replaced again as a result of me bugging her earlier this year, it died less than 2 weeks later and had to be replaced AGAIN (actually she's up to her 5th replacement within about 2 years). Solar company seems to have heaps of these cheap inverters lying waiting around for warranty repairs, which have
6+ year old production dates on the label.
The solar company responsible for installing knows about the issue and claims the inverters have nothing to do with RF and said instead that it's the mains cables being too close to the telecommunications cables, meaning a fault in the home's wiring. We had the neighbor's home checked out by the electrical safety officer for our area, he said there's nothing wrong with the mains wiring but can't say for the telecommunications (out of his area). The solar inverter was installed prior to Australian laws requiring an RCM approval mark on electrical equipment (pre-2015), meaning they are not required to comply with EMI standards, at least according to the Clean Energy Council.
My guess on the problem is that the inverter, being cheap chinese junk, is missing the required DC filtering to reduce the EMI. As a result, huge currents of the solar panels at frequencies identical to those used by AM radio (500k - 1600k) and by ADSL (25k - 2MHz) are being switched on and off, which is then producing huge electromagnetic fields. These electromagnetic fields are then being induced into the neighbours telecommunication cables, down the underground piping, down about 100 metres of cable between our modem and the neighbours property. The PWM generation of the inverter is probably the part being induced onto the line, which under normal conditions should be filtered but here it's not.
This graph is a plot of my ADSL connection's noise margin recorded over a period of the day. As the solar equipment starts working, you can see the connection quality (noise margin) takes a plummet. Then during sunset, it returns back to normal.
In this test in the morning, the router is trying to get a connection. As a result, you can see there are hours of dropouts during 5am - 8am where the router is constantly restarting and unusable.
My router will allow me to dump SNR and QLN values for each ADSL channel/bin. The colours represent different times the SNR values were recorded. When the solar equipment is on/off, the SNR of the channels/bins will significantly decrease, some will become too noisy to use (thus means less bandwidth/speed for the ADSL). In this graph I compare the SNR from 7am, 8am, 9am, 10am, 11am and 12pm as the solar equipment operates during the day.
Around bin 115, the SNR goes from about 37dB at 7am down to 0db!!!!!!These were captured at night time. I tried to use my Rigol DS1102E scope to check out the telecommunications line using the math FFT, but for some reason it only shows the upload portion of the ADSL signal. No idea what that jumpy signal is towards the end, maybe part of the ADSL?
This is when I disconnected the ADSL router, showing this signal correlates with ADSL (well it is between 26khz and 130khz)
I've tried putting ferrite core rings wrapped on our telecommunications line with hope to get rid of some of the noise, but no luck. We currently use ADSL2+, but later this year are going to be upgraded to NBN which uses VDSL2. VDSL2 uses frequencies up to 25MHZ, I wonder if it will continue to be an issue. I also considered putting a faraday cage around the neighbours inverter, but I don't know how she'd feel about that. I've had suggestions of putting a filter on the DC side of the inverter but that would come at my expensive to hire an electrician to do that.
Any ideas?
Feb 2019 - Edit: My neighbour got this in the mail:
We are getting NBN in likely 2 weeks. Will post update then.
Please read my update