Inheriting a challenge

championc · 21-07-2022 2:38pm

Certainly sounds like it's raised alarm bells with them, which is good in that THEY will have an "issue" to resolve, rather than you having to tweak stuff to overcome the issue.

mp3guy · 21-07-2022 3:54pm

Yeah sounds like things are moving in the right direction.

championc · 21-07-2022 4:19pm

It may we'll be the more constant nature of voltage rather than possibly just spikes here and there.

Chris_5339762 · 21-07-2022 9:04pm

Another update! Thick and fast now. The ESB man came to the door today, and after a small bit of effort, had also confirmed that the neighbours house is high as well.

Saturday hopefully they're going to have a look at the transformer and change the dipstick on it. If the transformer does not have a dipstick, they'll put a new transformer in.

Whilst I still don't know for sure what the measurement was, in/around 249V constant I think, it has lit a bit of a fire under them all of a sudden. Hopefully this will solve the solar problem too and will mean we don't have to adjust the inverter - shouldn't need to if they drop the voltage a bit.

Chris_5339762 · 26-07-2022 2:27pm

Another update!

Two houses are served from our transformer. According to the ESB, that transformer was put in 30 years ago when the 5000V main supply was low, so the transformer was set to high. However now that the 5000V main supply has been well upgraded, the transformer needs to be reduced but it can't be.

So a new transformer is going to go in. The bad news: They can't do it for three weeks, until the corn in the field where the pole is has been cut and they can get their lorry in!

So more updates then. Interesting though that the voltage is the highest today that I've ever seen it- the solar hasn't switched on today at all. The inverter is reading 256V, so in reality its probably a stable 254V or 255V at the mains, which is ludicrous.

championc · 26-07-2022 2:58pm

It's possibly a transformer long forgotten about, or maybe was state of the art at that time. In any case, I think indeed, you've highlighted an issue which they need to solve for their own network

mp3guy · 26-07-2022 3:03pm

Nice! Sounds like you're home free. Great record for the many, many folks who will be running into this problem in the next few years :)

I just rang up my local ESBN office to see if they'll consider doing something similar for me.

Chris_5339762 · 26-07-2022 9:07pm

I hope so! A lot of hoops to jump through but we'll see.

Challenge after this: Big battery!

championc · 26-07-2022 10:06pm

A DIY 10kWh one ??? Or even go 20kWh !!!

10-10-20 · 27-07-2022 4:36pm

I don't understand this part:

"The engineer that put the monitor on actually said we're lucky to have it at the high end(!) He says that since the resistance in the house is constant, because we have a higher voltage we have lower current, so electricity costs us slightly less!"

The ESB charge by the kWh which is calculated by multiplying the measured voltage by the measured current, so how can you be lower in the current if the voltage is higher and have fewer watts used?

ie:

230v * 10A = 2300W

235v * 9.78A = 2300W

255v * 9.02A = 2300W.

Unless I'm missing something, he was possibly blowing smoke up your ass.

Tow · 27-07-2022 4:54pm

Did you ask to see his 'Engineering' qualifications 😜

championc · 27-07-2022 5:34pm

I bet all you were thinking was "I don't give two fools - just get it sorted" !!!

Hotblack Desiato · 27-07-2022 6:38pm

https://www.boards.ie/discussion/comment/119395132#Comment_119395132

Assuming a purely resistive load, P = VI = I²R = V²/R so increased voltage across the same load means more current and more power dissipated, in proportion to the square of the voltage

That might be OK with your 2-bar heater, you or the thermostat just turns it off sooner, not so good with incandescent light bulbs and the like (use more energy and go pop sooner)

championc · 27-07-2022 7:43pm

I think I must have missed that day in school 😂😂

Chris_5339762 · 03-09-2022 12:45pm

It's been just over a month now since my last update and things have been resolved at long last.... not quite in the way we planned but it was sorted in the end.

Recap: ESB told us that the grid voltage was too high (about 250V) and that they'd replace the transformer but couldn't do that until the field the pole is located in got harvested.

We didn't need to wait that long. There was a major power outage at the main substation in the town we live in about a week later. Something big went bang. When it came back later that day, things were badly wrong. The grid voltage started out at 252V, no solar at all - above the limit set in our Inverter. It crept up. 253V, 254V.... it got as high as 257V before something major in the town tripped again. Some tinkering later and the ESB had the power back on again, but now around 245V.

The solar has been absolutely fine without cutting off once since then. And last week, the transformer got replaced at long last, and our voltage is now around 235V, which is perfect and does not stress out our electronics. It turns out there are only two houses on this transformer as well, but god knows what the rest of the area is like. The only remaining problem is that ESB are seeing 60V on the negative which suggests leakage somewhere, but they are fairly sure it is on their side, not ours. Self-installed garage and shed electronics were all disconnected in case, but it's not them. (My dad installed them, he used to be an electrical engineer and although he wouldn't have Irish qualifications is perfectly competent).

So the solar is now working without a hitch. We will now pay the installers their final batch of money, wait to get the grant, and then get at the very least a battery.... maybe another rake of panels on our other roof (Along with a new inverter sadly, they only gave us a 3kW one).

Longer term: Still more panels and an electric car. Probably a few years though.

Hotblack Desiato · 03-09-2022 2:20pm

Totally mad that the ESB would allow a domestic supply voltage to exceed 250V. All domestic sockets, plugs, appliances etc. are only rated to a maximum of 250V (some appliances less than that). It's unsafe.

bullit_dodger · 03-09-2022 3:06pm

https://www.boards.ie/discussion/comment/119564885#Comment_119564885

Ahh not that I condone it, but a few volts wouldn't make stuff unsafe. The official SLA from ESB is 230 +/- 10%, so that's a low as 207v and as high as 253v. Within that range they are fulfilling their legal obligations. If you pushed to 255v or even 260v things wouldn't suddenly become a death trap, things wouldn't have such tight tolerances..... but yeah, it's not good for things.

Great that you got sorted Chris - and also for keeping the folks here updated. It's been quite the journey.

allinthehead · 03-09-2022 3:53pm

Are installers fitting surge protection?

Chris_5339762 · 13-09-2022 10:53am

Just when I thought all was calm on the western front.... an order has gone in for a 5kW battery and four more panels.

Installer says we should be fine on our 3kW inverter as they will be on a seperate string... I'm guessing we'll have about 4.5kW peak without any shadowing.

I think we are marginally overpaying for this, but its not my money at the end of the day. It'll all hook into the Eddi as it stands. In years to come I'll put up 8 or 10 west facing panels on the garage room and maybe a ground array on the lawn to deal with an EV, but thats in the future. For now, it'll be good to get the battery in but I'm a little jaded from dealing with things up to now!

bullit_dodger · 13-09-2022 11:03am

https://www.boards.ie/discussion/comment/119611244#Comment_119611244

Installer says we should be fine on our 3kW inverter as they will be on a seperate string... I'm guessing we'll have about 4.5kW peak without any shadowing.

Just to clarify that your aware, you might have 4.5Kwp in generation power, but a 3Kw inverter will still only "draw down" 3kw max from your panels. That said, with the extra panels you'll see an overall bump in your production for the year, as while you will experience "clipping" for some days, but for many where you were previously generating (say) 1.2Kw, that will rise now to 1.8Kwp or something.

slave1 · 13-09-2022 1:16pm

What he said.

We "oversize" in Ireland due to not having a perfectly South shadeless option possiblly but definitely Winter months with low sun and a lot of rain/clouds throughout the year , you'll need 4.5kWpotential to give you 3kW actual generation

Chris_5339762 · 13-09-2022 3:10pm

We get 3.3kW "delivered" peak off our current setup and I do see clipping even now - on a good sunny day it doesn't go above 3.3kW and flatlines at that level... so I guess we'll just have to get used to more of it but an improvement overall. It's a bit frustrating but I don't think getting a 5kW inverter is justified on top of all of this, given our 3kW one is only 6 months old.

Battery will still fill up and thats the main thing I guess - and it'll fill up for longer as we have more generating potential.

slave1 · 13-09-2022 5:31pm

Your "flatlining" will soon be over, we've had a great August and now the past few poor days are over it looks good again for the next short while

championc · 13-09-2022 6:55pm

https://www.boards.ie/discussion/comment/119612768#Comment_119612768

It more means that the battery will fill up sooner. That array would support a 10kW battery

Chris_5339762 · 14-09-2022 10:25am

I was pushing for 8kW but the price for 5kW vs 8 was nuts.

The good news is that its a modular battery that you can buy in 5, 10 or 15kW variants. The 10 or 15 are just three 5kW ones stacked with a control module. So maybe after a while we could buy our own 5kW, do a bit of youtubing and some begging for advice on here, and upgrade it to 10kW.

bullit_dodger · 14-09-2022 12:10pm

https://www.boards.ie/discussion/comment/119616158#Comment_119616158

There's a whole thread on it (Solar batteries), but with the FIT being as lucrative as it is (€0.13-0.14 for most and some reaching €0.20) a larger battery is a questionable endeavor. Definitely think a small-medium battery which you have Chris is a good thing to have, not least of which it will help in winter lessen your bills by being to able to charge at night rate and use during the day saving you some day rate usage. Also ultimately it will help when we have to contend with "peak rate" on the smart meters that you can ride through those 2-3 hrs.

That said, it's not all about money either.

Chris_5339762 · 15-09-2022 9:21pm

I've pushed my folks away from getting a smart meter - we did have to get a new meter as part of the original works and I said a categoric no to a smart... we have day/night rates and the smart day/night rates are absolutely awful by comparison. Maybe its not quite as bad as it used to be but yeah, I said no to a smart meter so we'd get the flat rate FIT if ever they sort that out.

Grant came in this afternoon for the original install! This got heavily delayed as we refused to sign off on it and they couldn't send the grant in until we were happy. Battery and additional panel install in a months time.

Chris_5339762 · 17-12-2022 12:02pm

Another update for those that are interested - we upgraded a few weeks ago. 3 additional panels plus a 5kW battery.

We now have

2x Old piped hot water on the main roof
8x 320w panels on the main roof
3x 400w panels on the side roof
5kW battery
3kW inverter (clips at 3.3kW) - not worth replacing as its less than a year old

All south facing, also we get a fair bit of reflection off the sea which I need correct cloud conditions to measure.

Voltage issues were solved as above and things are working well. The system is powerful enough to run the house and charge the 5kW battery in December if we get a sunny day and electric fires are not switched on.

There are a few new minor issues, with the installer so up the walls with work we just can't get them to reply to our queries at all.

1) The installer put the 3x 400w panels on the same string as the 8x 320w panels. This seemed odd, as the original plan was to put the 3x 400w panels on the second string. Is this an issue really? There will only be minor shadowing, if any, due to the height difference between the two roofs. Should we push them to put the 3x panels on the second string and what benefit would there be?

In time, I want to put another 8-10 panels on the westerly facing garage roof, to provide electric car or PHEV charging in the summer evenings after work. But that'll need a second inverter or an inverter upgrade so I'm not worried about the second string for that.

2) The installer said the inverter is fine up to about 4.5kW. Not sure what to think about that when it already clips at 3.3kW. Would putting the new panels on the second string increase the level at which the inverter clips? Or can the inverter only "invert" 3.3kW of power regardless of what string it is coming from?

3) The biggest issue. The installer has changed the default password on the inverter wifi and I can't access it. They won't respond to requests for the new password either. (Scanning the QR code doesn't work either) When we rang up about the battery config, the secretary said she could change things from her end. I don't want that. I want to decide, every night based on the weather forecast (which I do myself - weather nerd here), whether to charge the battery to say 80% off night storage. Is this set up through the FusionHome app, and is there a way to reset the password on the Huawei inverter without changing any other settings? (I doubt it or its a pretty big security hole).

Thanks a million!

slave1 · 17-12-2022 12:44pm

Your 400w panels being on the the same string at 300w panels are outputting at the lowest level of the string i.e. 300w
Your 3kW Inverter can take 4.5kW of panels but that's because rule of thumb you can oversize by 50%, this helps in cloudy days and poor times of the year. Your Inverter is maxed at 3.3kW, no matter how much you put into it, it will never produce more
Installer issue, I would not like that either

championc · 17-12-2022 7:46pm

Just to add

It's very likely that the startup voltage of 3 panels on a second string is too low.

Keep a look out for a cheap second hand standard PV inverter for the garage

Also, I'm surprised a 3kW hybrid inverter has inputs for two strings. Are you sure ?

Maybe you need to start researching being able to do a factory reset of a Huawei

Inheriting a challenge

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