Funny Electrical Discharge Noise

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Joined: Sat Mar 21, 2020 4:37 pm
My RE system: outback skybox inveters

Funny Electrical Discharge Noise

Post by dpallotta » Sat Mar 21, 2020 4:39 pm

I have 2 Outbox Skybox Inverters. Almost daily, both inverters make this strange sound and the best way to describe it is that its like a discharge of electricity and it usually lasts about 3-5 seconds before it goes away. Today I can confirm that I have heard it twice. I just want to know whether or not this sound is something that is normal and should be expected. If it is, what exactly is happening when I hear this sound? I get no errors or warnings. It just doesn't sound like something I should be hearing and I want to make sure this behavior is normal.

Something I should also note is that I only ever hear this noise when the PV system is producing electricity. I have never heard it at night.


Mike Curran
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Posts: 1394
Joined: Sat Aug 28, 2004 6:28 pm
My RE system: Outback - Garage roof:
- 8 (2x4) Evergreen 180's into one MX60 (2007)
- 6 (2×3) ALEO S79-300's into one FM80 (2017)
- 2 grid-tied GVFX3524's classic stacked for 120/240VAC (2007)
- 12 Surrette/Rolls 2V x 1766Ah (2007)
- Hub10.3, Mate3s, FNDC, RTS, OpticsRE. Tigo Energy ES maximizers on each PV module.

Westinghouse Solar - Barn roof: (2012)
- 30 (2x15) 235W panels with Enphase M215 microinverters, grid-tied, no longer AC- coupled

Outback Skybox - Barn roof: (2019)
- 14 (2x7) Talesun 275W (DC array input to SB charger)
- 3 SimpliPhi 3.8 batteries, 48V, 225Ah total
- AC coupled input from 14 Talesun 275W, Enphase M215 modules

All self-designed and self-installed
Location: Chagrin Falls, Ohio

Re: Funny Electrical Discharge Noise

Post by Mike Curran » Sat Mar 28, 2020 7:43 am

Mine does not make any noise like this.

Is it possible to observe the inside of the BOS when this is happening? Sounds like arcing?

Since you're only hearing this when there's PV input, I would check your PV connections inside the Skybox BOS to make sure they are secure.

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