Grid under voltage alarm

ac3tylene

Hi all,

I got solar pv with a solis inverter and pure drive battery a few months ago.

Everything usually works the way it is supposed to but in recent days I've been getting a recurring notification from the inverter saying "grid under voltage". After a while the alarm is 'restored'. When I look at the app it shows that during this time the battery is not used. Instead all energy is pulled from the grid.

The first time this happened (several weeks ago) I called the installer and they let me know that this is an anomaly of the Irish electrical grid and not to be concerned.

The issue I'm having is that in the last week the alarm has occurred multiple times per day.

There seems to be a tendency for it to occur often (but not always) between 4pm and 7pm. It is not occurring at all between midnight and 7am.

I'm just wondering if this is something others also notice?

Thanks in advance

graememk

If its alarming out for low grid, then either the settings on the inverter are wrong or the grid is actually going very low (sub 191 volts) Or the inverter is reading the voltage of the grid wrong (I have come across that, fixed via solis support with an update)

you should have some logging of the grid voltage on the app for your inverter

ac3tylene

So it appears to be alarming out when the voltage is below 220. Or else I'm reading this chart wrong.

graememk

https://www.boards.ie/discussion/comment/121632025#Comment_121632025

Need to move the selector a bit more to the right to that dip.

ac3tylene

That is at 211 volts

ac3tylene

Ok I opened a ticket with Solis support and they told me that the grid voltage is unstable here, and I need to adjust the grid code.

They suggested that I could make it 'user defined' but I wouldn't know what values to set for this, so I changed it to 'esb-micro' and haven't gotten any alarms in the last couple of days.

So hopefully that has sorted it, tbh I'm not really sure what it all means but at least I'm not getting notifications every hour now

graememk

https://www.boards.ie/discussion/comment/121642842#Comment_121642842

What was it set on before? Esb micro is the newer standard (and a bit looser on its settings)

ac3tylene

It was EN50549IE previously. I looked at the grid voltage a few times since and even though the voltage has dropped since changing it hasn't caused an alarm so I guess it's probably a better setting for this setup

jkforde

My RHI-5K-48ES-5G (FW 350025) inverter doesn't have the ESB-Micro option on it but the remote facility via the app offers it but it never sticks, I assume because the inverter needs it on it first! I've opened a ticket to Solis anyhow.

Jonathan

https://www.boards.ie/discussion/comment/121647531#Comment_121647531

That's an old enough firmware. It was added in a more recent firmware.

Would suggest changing grid settings manually on inverter screen. I tried changing via app before and it changed it to Brazil (60Hz!).

jkforde

thanks Jonathan, I opened the ticket on Monday morning and they updated the firmware on Tuesday morning, super service in fairness.

con747

https://www.boards.ie/discussion/comment/121642941#Comment_121642941

I had the same problem and changed the setting to esb-micro as well after seeing your post and seems to have sorted it but unsure with the power cuts here so no stable supply to find out 100% yet. I will say though I was getting 4+ a day due to I imagine farm related draws and I have none in 2 day's now so thanks for that.

KCross

https://www.boards.ie/discussion/comment/121632287#Comment_121632287

Maybe you should also check if ESB can improve your voltage.

Their default response will probably be that it’s within spec but might be worth an ask anyway.

graememk

https://www.boards.ie/discussion/comment/121663113#Comment_121663113

Esb micro is a bit more forgiving on the grid limits Vs en50549IE (I think it's minimum of 191 and max of 267... It's on the NC6)

Scoobydoobydoo101

Anyone having issues with the ESB Micro standard?

When the inverter goes offline the alarm goes off. When it come back online the alarm stays on until I change it back to EN50549IE. I can then change it back to ESB micro straightaway...

con747

https://www.boards.ie/discussion/comment/121664504#Comment_121664504

I have the hybrid inverter and batteries with no issues of it turning off, is your's a string inverter or hybrid with batteries?

Scoobydoobydoo101

I have a hybrid

con747

https://www.boards.ie/discussion/comment/121666242#Comment_121666242

Batteries?

Scoobydoobydoo101

That would be helpful! Yes I have a weco battery

con747

When you say it goes offline do you mean it shuts down or loses connection to the internet? It will help others who have much better tech knowledge than me to help!

Scoobydoobydoo101

Hi Con, so if the grid goes down the fault alarm turns on. The grid comes back the fault alarm stays on until I change the grid standard.

con747

https://www.boards.ie/discussion/comment/121668692#Comment_121668692

Maybe it resets to a default setting?