Strange noises from inverter just after sunset

[WibbleWobbleWoo]

Hi,

This is my first post here and I'm hoping someone might know what this is. I had my system installed at the end of April. All seems to be working fine, but I've noticed that just after sunset each evening that there are some quite loud clicking, humming and arcing sounds coming from the top right rear corner of my inverter. Looking on the Fox ESS Cloud website there are some crazy spikes where I'm importing, exporting and charging the battery during these times. I can also see similar patterns just before sunrise in the graphs too, but that's too early right now for me to check if the same thing is happening. Here are a couple of screenshots:

I've mentioned this issue to my installer already but they haven't got back to me yet with any indication of whether this is normal or not. This issue seems to be causing most of my daily grid imports, so it would be great to get it sorted if this isn't meant to happen.

My inverter version numbers are: Master 1.48, Slave 1.02, Comm 1.49, and batteries: M: 00.01.004, S1: 01.00.01.01, S2: 02.00.01.01.

All help greatly appreciated, thanks!

Russ.

[WibbleWobbleWoo]

Hi,

Just wanted to post an update on this. It is still happening every evening, usually starting about 10 minutes after sunset (or earlier if cloudy) and it lasts for about 10-15 minutes. Last night while it was happening I looked at the display panel on the inverter and the Power value was rapidly flicking from around -3500 to +3500 the whole time. I took a couple of pictures:

I have noticed that if I throw the DC input breaker switch on the bottom of the inverter while it is doing this everything returns to normal. Switching the DC breaker back on again and the crackling/popping sounds start and the crazy flicking between large +/- values starts again too. I'd love to get to the bottom of this because I'm consuming upwards of 1kWh of grid electricity every day because of this issue.

All help appreciated!

Cheers,
Russ

[calum]

Cracking and popping sounds like arcing which is not something you want to continue. I'd get your installer back to check everything, could be a connection issue with the HV DC lines or an issue with the inverter itself.

If installer won't come back then you'd have to raise a ticket with Fox UK.

[JustinDallas]

We had the same arcing sound issues and +5000 to -5000w showing in the Fox panel. Our LED lights would also dim and flicker - also lasted around 10mins every morning and evening.

Fox were able to run a firmware update remotely - and that solved our issue. Ask your installer to arrange that for you.

[WibbleWobbleWoo]

Actually I can confirm that latest firmware fixes the issue for me also

My installer came out two weeks ago and replaced the inverter, but the problem continued. Both inverters were on the same 1.48 firmware so I guess that would explain why. Fox remotely upgraded mine on Friday and I've not had any problems since.

Cheers,
Russ.