Loud humming noise neighbor's solar panels

[May]

Is it possible the noise is not the solar panels and coming from a different source?

Andy

Thanks for asking. I don't think so Andy. The noise starts within minutes of the sun coming up. I am in the country. This is my childhood home. Super quiet for decades. The noise started last year within days of new new roof going up and panels going back on. The brighter the sun the noisier it gets. On dull days it's not quite as bad.

[May]

Frequency buzz source identifying can be misleading,
It could be worth asking the neighbor to make a test during the day when you are hearing it, and shutdown their solar system for a short while to see if the noise disappears.

Thanks for that. I will do that. However it all starts when the sun comes up as soon as it's daylight. This is my childhood home. Quiet for decades until the new roof went up last September and their panels put back on. It was so quiet during winter. I thought it had gone away.

[May]

It would be good to know the frequency as suggested above. I suspect the power
line, 50 HZ for you? And does the strength rise and fall over the day. Really I do
not see how it could be the DC panels, but rather the inverter (a single string inverter?)
or its connection to the line. Good to check the inverter output numbers while this
is going on.

If it is micro inverters, the source will move to their mounting at the panels, likely
just one has a problem. good luck, Bruce Roe

Thanks Bruce. I don't know anything about frequencies. Yes the noise rises and falls during the day. Very loud on sunny mornings. Softer on dull mornings. It can stop late afternoon then start up again. I don't know if they are switching it off and on. I will ask them to record numbers if they can.

[May]

It's a great concept that, like many on paper look great, then get mucked about in the execution.

I have many friends in and also from Scotland as well as some shirttail kin.

Whaur urr ye located ?

Best Regards,

J.P.M.

Hi JPM. Am outside Glasgow in the country - South Lanarkshire. Not a bad accent! This is a nice, friendly site. It's so helpful for me. I want my life back! Lol.

[J.P.M.]

Hi JPM. Am outside Glasgow in the country - South Lanarkshire. Not a bad accent! This is a nice, friendly site. It's so helpful for me. I want my life back! Lol.

May: after rereading all the posts to this thread, my money would be with the inverter rather than the panels as the culprit but maybe if the system is equipped with microinverters rather than 1 or perhaps 2 string inverters, the connection or wiring between one or more panels and its inverter may have gotten loose.

Also, is the noise any louder in one portion of your dwelling than another ? Or, if the system uses string inverter(s), is the noise any louder near where they are located ?

I believe I understand your reluctance to get the system owners involved, but as onerous as it may sound, you may need their involvement if for no other reason than what you describe may be an indication of an unsafe condition that came about when things got moved.

As for accents, Thank you for the compliment. I take your comment as high praise, coming from a Scot as it is. My kith & kin have had me in training for about a half century.

[scrambler]

Thanks Bruce. I don't know anything about frequencies. Yes the noise rises and falls during the day. Very loud on sunny mornings. Softer on dull mornings. It can stop late afternoon then start up again. I don't know if they are switching it off and on. I will ask them to record numbers if they can.

If directly related to solar, it would go down with large shade on the panels, like grey clouds

[robbyg]

If directly related to solar, it would go down with large shade on the panels, like grey clouds

There is Audio spectrum software for the iPhone and Android phones that can pick up sounds beyond the hearing of humans and display it on screen like a spectrum analyzer. The software is typically like $5-$10. With that you can isolate the frequency of the sound. Once you have the frequency it's a lot easier to find out what is going on. Since your friendly with the Neighbor get the information on the Make and model of the Inverter and then call the company and ask for an engineer. Explain the problem and tell him the Frequency of the sound. If he is any good at his job he will know if that sound can be produced by the inverter and the reason why.

[sdold]

When you hear the noise, can you walk over and ask the neighbors if you can stand close to the inverter to see if that's where the noise is coming from? This should be an easy thing to do, unless the inverters are microinverters where one is under each panel.

Also, there might be a circuit breaker for the solar array that could be turned off to see if the panels and inverter are the problem.

Have you tried either of these yet?

[peakbagger]

A "high tech" tool to use is a long tube like a cardboard of plastic tube a bit larger than your ear, the longer the better. Now with the tube up against your ear move the end of the tube around pointing at different points on the installation. On a quiet day without a lot of background noise its a useful tool to pinpoint noise sources.

My guess is the fan on the inverter, One of my Fronius units makes a fairly noticeable hum when running. The fan cycle on and off during the day.

[PVAndy]

Thinking back we've had some inverter noise complaints. In some cases it's been a defective fan. In a couple of cases it was a vibration of the panel cables caused by the wind.

Most if not all current inverters use high frequency switching above the range of human hearing

Andy

[Batmain]

Hi, has anyone been able to find out where is the loud humming sound coming from? I have a rooftop installation and it sometimes gives off a loud humming sound like a boat motor running when it is bright and mostly happens around 9am about sunset. It lasts about 4 minutes each time.