Inverter with my Solar system make a noise! why?

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General_Lee   10 W

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Inverter with my Solar system make a noise! why?

Post by General_Lee » Apr 26 2018 7:52am

Hi guys, I bought a PowerBright ML2300-24 inverter, I tested it and when I plug a devices the inverter make a inside noise. Is it normal? this noise is not good to ear!

I plug a PC computer on it and the power supply on this PC make a noise to.

What is the problem?

Thanks.

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Alan B   100 GW

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Re: Inverter with my Solar system make a noise! why?

Post by Alan B » Apr 26 2018 8:23am

Inverters often make some noise. This particular unit is putting out a "modified sine wave" which is actually a square wave with three states - low, zero and high. This causes the AC supply in the load to make noise. The square wave is not a nice clean 60hz sine wave that is the normal for AC power, it has harmonics across the audio spectrum that you can hear.

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General_Lee   10 W

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Re: Inverter with my Solar system make a noise! why?

Post by General_Lee » Apr 26 2018 8:34am

Alan B wrote:
Apr 26 2018 8:23am
Inverters often make some noise. This particular unit is putting out a "modified sine wave" which is actually a square wave with three states - low, zero and high. This causes the AC supply in the load to make noise. The square wave is not a nice clean 60hz sine wave that is the normal for AC power, it has harmonics across the audio spectrum that you can hear.

This is bad for the devices plugged on it? like I said, I use a computer and I ears a noise from the Power Supply. I not ear that when it plugged to home wall AC or APC UPS.

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Alan B   100 GW

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Re: Inverter with my Solar system make a noise! why?

Post by Alan B » Apr 26 2018 8:54am

General_Lee wrote:
Apr 26 2018 8:34am
Alan B wrote:
Apr 26 2018 8:23am
Inverters often make some noise. This particular unit is putting out a "modified sine wave" which is actually a square wave with three states - low, zero and high. This causes the AC supply in the load to make noise. The square wave is not a nice clean 60hz sine wave that is the normal for AC power, it has harmonics across the audio spectrum that you can hear.

This is bad for the devices plugged on it? like I said, I use a computer and I ears a noise from the Power Supply. I not ear that when it plugged to home wall AC or APC UPS.
If you do some searching on "modified vs pure sine wave" you can find articles and videos answering this question in more detail. In some cases it works fine even though it might make noise. In other cases it makes the power supply warmer than usual. In yet other cases it does not work or even causes damage. It depends on how the load reacts to this waveform.

billvon   100 MW

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Re: Inverter with my Solar system make a noise! why?

Post by billvon » Apr 26 2018 10:38am

General_Lee wrote:
Apr 26 2018 8:34am
This is bad for the devices plugged on it?
For some devices, yes. It depends on how they are designed. It's very bad for any motor based appliance (refrigerators, pumps.)
--bill von

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General_Lee   10 W

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Re: Inverter with my Solar system make a noise! why?

Post by General_Lee » Apr 26 2018 11:24am

billvon wrote:
Apr 26 2018 10:38am
General_Lee wrote:
Apr 26 2018 8:34am
This is bad for the devices plugged on it?
For some devices, yes. It depends on how they are designed. It's very bad for any motor based appliance (refrigerators, pumps.)
Thanks, Having known, I have not checked this before :oops: . My mistake, I know now the best is Pure sine wave.

robby p   1 mW

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Re: Inverter with my Solar system make a noise! why?

Post by robby p » Oct 09 2019 5:22pm

I had to chuckle at this. I work in utility PV and some of those 800-1800kW central inverter’s really can make some seriously loud, annoying noise at high gating intensities.

SMA is a very popular inverter and we’ve joked that it stands for Sound Making Apparatus.

robby p   1 mW

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Re: Inverter with my Solar system make a noise! why?

Post by robby p » Oct 09 2019 5:57pm

Here is the shortest clip I have that demonstrates the sound. I occasionally make these how-to videos for new hires & such where I work. This is just part of a longer video explaining how to perform one specific aspect a larger routine maintenance task. I’m essentially having to shout over the noise.

https://photos.app.goo.gl/WKCxFDtfpTvnjzC68

Hillhater   100 GW

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Re: Inverter with my Solar system make a noise! why?

Post by Hillhater » Oct 09 2019 6:10pm

robby p wrote:
Oct 09 2019 5:57pm
Here is the shortest clip I have that demonstrates the sound.

https://photos.app.goo.gl/WKCxFDtfpTvnjzC68
The link seems to be just a photo robby. ?
This forum owes its existence to Justin of ebikes.ca

robby p   1 mW

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Re: Inverter with my Solar system make a noise! why?

Post by robby p » Oct 10 2019 5:09am

That’s weird. Let me try again
https://photos.app.goo.gl/T2d1VchwvJHXS1p26

I guess I could put it on YouTube but I don’t think I’m ready to take “Robby’s PV TV” live yet :lol:

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