2.88kw system with 2.5kw inverter ?

[Scobo]

Hello guys.
1st post here so please be gentle. :tongue3:
Just had a 2.88kw installed this week.
We were meant to get a 3kw Fronius IG Plus but I've just noticed the model number on the base of the inverter says Fronius IG 30 which is rated 2.5kw from what I've read.
The part number is 4,200,003.
Maximum output reading on the inverter so far is just over 2500 watts.
Does anyone know from the part number if this is indeed the lower rated model and if so, would we be better with the Plus model at 3kw ?

 

[whinmoor]

In general terms, you should have received what you were quoted for and what you ordered.

Please tell us the number of panels, make, model. Also, your rough location, the orientation and pitch of the roof. Is the inverter in the loft, garage or somewhere else?

 

[moggy1968]

depends a little bit where you are in the country and what the orientation of your array is. Your doing pretty well to get 2.5kW at this time of year from a 2.8kW system! The IG plus is more efficient so should have better yields, the IGTL even more so (around 5% more efficient). The inverter you have been given is also signnificantly cheaper than the plus or the TL, so you should have had a price reduction.

 

[Scobo]

Thanks guys.
Roof is south facing, 12 x REC 240Wp panels, inverter is in the loft, not sure about pitch and we're in Fife, Scotland.
I thought 2.5kw was pretty good for this time of year but the the guy who sold us the system said we should definitely hit 2.9kw later in the year with the setup we have.
Just not convinced that our inverter is the Plus model judging from the model number on inverter in which case I don't see how it will go over 2.5kw.

 

[babba]

TL and plus are more effecient you have IG30 peak 2.65kw but TL and plus may be a little too big.. Swings and roundabouts really..

 

[Scobo]

Yeah, I read in other posts that an inverter rated slightly lower than the max output of the panels is usually recommended so I guess the one we have should be ok in that case.
Just assumed you would need an inverter that at least matched the power output of the panels.

 

[babba]

I think you will be fine but I realise you have been mislead by the salesperson..

 

[Scobo]

Think it's maybe just been an oversight.
Otherwise the company were great.
They installed it in one day within a week of me contacting them and pulled out all the stops to beat the March deadline.
So you don't think there'd be any great advantage in changing it to the Plus model then ?

 

[babba]

no I would stay as you are not worth the hassle for no extra kwh..

 

[whinmoor]

Did you get the Fronius 20 year warranty? It shows the manufacturer has confidence in its products. I think a slightly undersized inverter is fine for your location so agree with babba above. The panels have a good reputation - either Swedish or Norwegian I think. It sounds like it's been installed correctly on the electrical side to be producing 2.5kW in early March. Assuming that the roofwork is ok, you should have a decent system for many years - enjoy it.

Fronius International GmbH - Keeping up-to-date - News overview

 

[Scobo]

Thanks for the speedy replies guys.
Yes, I'm sure the guy said the panels are from Norway.
Haven't got the warranty yet but will look into that, cheers.

 

[GaryM]

Haven't got the warranty yet but will look into that, cheers.

Was a warranty extension part of the package your installer offered?
If not then I doubt you would get it as it does have to be paid for. I think the standard warranty is 5 years.

 

[moggy1968]

I really don't think the extended warranties are worth the money TBH, they're very expensive.
It's like buying extended warranties on your white goods, just not worth it.

 

[dansk]

true, and by the time it needs replacing the actual cost will have dropped to the cost of the extension anyway.

 

[moggy1968]

Also some companies (SMA for example) will recondition an inverter for considerably less than the cost of a new one.

 

[GaryM]

I possibly wouldn't have paid for my extended guarantee but it was added as an extra to convince me to go with the company I did.
20 year piece of mind was a good addition for me as I feel there's a good chance the inverter will fail during that time.

 

[moggy1968]

there have been some offers on warranties from manufacturers so that may be why your installer chucked it in. With the offers it was more atractive.

 

[whinmoor]

Perhaps an under-sized inverter is more like to fail due to being max-ed out more often? Also, if it's in a hot loft, its lifespan could be shortened.

It really comes down to the customer. Some would like the peace-of-mind and go for it. Others would take the basic 5 years and hope for the best.

 

[GaryM]

there have been some offers on warranties from manufacturers so that may be why your installer chucked it in. With the offers it was more atractive.

Yes, it was part of Fronius' 20 year offer.

 

[Scobo]

Our inverter just rebooted and had state code 308 on the display panel which the manual says means the circuit voltage was too high.
Its now running fine.
First time I've noticed it do this.
Is it just something that happens from time to time or should I contact the installer ?

 

[babba]

whats the weather like...

 

[Scobo]

Very changeable.
Clear sky, bright sun one minute and getting 2kw, thick cloud the next and down to 200 watts.
It just restarted again with same status code.

 

[babba]

sound as if its grid voltage do you know what the grid voltage is..???

 

[Scobo]

No idea mate, will the inverter show that ?

 

[dansk]

Reading your OP, its seems like you have a IG Plus as ordered becuase the IG30 doesnt have a fault code 308. As Babba says its grid voltage.

How far is the inverter from the fuse board?

 

[Scobo]

Reading your OP, its seems like you have a IG Plus as ordered becuase the IG30 doesnt have a fault code 308. As Babba says its grid voltage.

Thats what I was begging to think too.
The manual we were given was for the TL models so I downloaded the IG and the Plus manuals and only the Plus manual mentions code 308.
But the Plus manual shows menu options our inverter doesn't have such as "yield".
Confused !!!???

 

[babba]

danst a voltage optimizator should sort this out...????

 

[dansk]

Poss - my next thoughts were AC radial to small for cable run. But without knowing a little more it would be hard to say.

Not too sure about Vphase units, not had much experience of them. Have you?

 

[babba]

only started to install Vphase but looking at it I think it would, not to familiar with IG 30 but we had a similar problem with a 4000 tl sma, took it out put in a power one and no problems.

 

[Scobo]

Forgot to say, inverter's in the loft about 5 metres or so directly above the fuse board.

 

[Earthstore]

Ah, Voltage optimizers, have been looking into these, there are various different one's on the market, some are better than others, however, you can not run PV back through them, PV has to be connected into the tails, after the meter and before the optimizer unit, so if over voltage from the grid is the problem an optimizer will not cure it.
As in most cases of overvoltage, it tends to be an install issue, not always though, granted.
I have my first voltage optimizer being installed this week, on a house that is a high energy user, so I will keep you all informed.

 

[dansk]

Would seem ok unless its on 1mm T&E!

Are you rural?

On the inverter you will be able to see max and min grid voltage - take a look would be good to know what the peak has been.

 

[babba]

If you are limiting V comming into the property to 230 from 250 I cant work out how this would not help..

 

[Earthstore]

If you are limiting V comming into the property to 230 from 250 I cant work out how this would not help..

As in my post, PV has to be connected before the optimizer, so voltage to PV would not be regulated.

 

[babba]

I got it after my post, I see what you are saying....

 

[Scobo]

You're losing me a bit now guys (I'm no spark).
The inverter is in constant standby mode now (I take it due to the sun having almost set) and it wont let me access the menu to see the max/min voltages.

 

[Earthstore]

Sorry, we are a bit like that.
The mains voltage coming into your house should be somewhere between 216V-253V, the DNO (people that own the electric wires, poles etc) have to keep it somewhere between these figures, sometimes the voltage can be on the high side, if you live in a rural location for example, however, sometimes a PV system, can make your voltage a little high.
On the inverter menu, there should be a menu for incoming supply, which should give a reading of around 220-240v AC,(between the figures above), and it may also store the history.
If the incoming supply goes to high for the inverter to cope, it shuts down to protect itself.
As someone explained about 1mm cable, if the install is not quite correct, this can also send your voltage up.
Me thinks you need an electrician who understands PV or the installer to pop back and have a look for you.
I hope this helps.

 

[Scobo]

Cheers (I can follow that).
I'd say we were semi-rural, not quite in the sticks but not in a big town or city.
A large village you could say.
The last status code was 306 which means its gone to sleep for the night according to the manual.
I'll check the voltage tomorrow when the inverter's running again

 

[noidea]

Hi
Sorry to hijack your thread but I have a similar problem. A friend of mine has a 4kw system, but with a 3kw inverter. The inverter in question is an Enasolar. There are 16 245w panels on the roof facing 170degrees with no shading issues on a bungalow roof in Kent. He was assured that the Inverter could handle anything from 2 - 5kw.??
Has anyone had any experience with these Enasolar inverters.

 

[Earthstore]

Just had a look at the spec, even though it should be able to cope, in my opinion it is a little small for that particular installation, a 3.6 would be more suitable, but Enasolar anly make a 3800, which is over 16A and therefore would make things a little more complex to install, so a different make would have been required, like SMA or fronius.
However this may not be the reason for inverter shutting down.
I hope this helps.