4000TL - not set up correctly

[langstroth2]

I'll be contacting my installer of course as well, but a second opinion is always helpful.

The 4000TL inverter had shut down this morning (early - so very little panel output) with a red light error indicator - but the error messages were in german so I don't know what the problem is. This makes me think that it's not set up for the UK correctly - or are the language settings no indication of setup.

I'm, sure I've read a similar thread on here somewhere, but couldn't find it via a search.

 

[SolarCity]

It does sound like the inverter was incorrectly set up. Do you have it linked to Sunny Explorer by chance?

 

[langstroth2]

It does sound like the inverter was incorrectly set up. Do you have it linked to Sunny Explorer by chance?

Unfortunately not yet - I've installed the sunny software, but my old bluetooth dongle isn't playing ball with Windows 7 (old drivers i think, no new ones available), so I'm going to have to get another one.

 

[SolarCity]

Did the system restart itself again or are the error messages still there?

 

[langstroth2]

Thanks for the quick replies. Don't know - unfortunately I'm not @home at the moment - had to leave for work. Will update later.

 

[langstroth2]

Did the system restart itself again or are the error messages still there?

It has re-started and is generating again apparently (quick call home)

 

[Mark.W]

Inside the inverter are 3 small dials, the first dial must be set to 5 and the second dial set to 8. This will ensure the inverter is set to UK settings. You cannot change it once the inverter has restarted more than 10 times and it will have to be programmed using sunny explorer! This is really easy to do and I'm sure your installer would be more than happy to do it for you! You also need to ensure that the inverter grid monitorng voltage is set to 261V not 253V!

Regards Mark

 

[SolarCity]

You also need to ensure that the inverter grid monitorng voltage is set to 261V not 253V!

Regards Mark

261v? For what reason?

 

[Mark.W]

261v? For what reason?

Not sure but this is what SMA told me themselves, it is the same with Fronius. I had a customer a while back that had an SMA installed and she was having problems with her inverter cutting out 10+ times a day. I contacted SMA who advised me to download Sunny Explorer and to check the settings of the inverter, they told me to set the grid monitoring upper voltage to 261V, which I did.... The customer has had no problems since!

Have a look at this attachment at the SMA under/over voltage actual setting!

http://www.wfsolar.co.uk/FileDepository/TechDocs/Inverters/SMA%20Sunny%20Boy%20Certificate%20G83%20-%201%20-%20SB%203300%20-%20SB%203800.pdf

 

[SolarCity]

I'm pretty shocked by that and concerned about the implications.

The DNO is responsible for maintaining a voltage below 253v. When someone connects a PV system, the voltage will inevitably rise - will the DNO blame the PV system for pushing the voltage high?

Looks like a compromise between SMA and the DNO and a pretty poor one at that.

 

[Mark.W]

The only real time to be concerned is if the mains voltage is above 249V, as this would mean the output voltage from the inverter would be above 253V. one could always ask the supplier to lower the grid voltage on their side! I suppose!

 

[SolarCity]

Install a few PV systems in a road and the voltage will be pushing 260, never mind 249v. A voltage of 260 will be damaging electronic equipment and should not be tolerated in my opinion.

 

[fiardor]

Ok I have 2 4000 TL's separately fed with 2 16A mcb's from a 2 way ccu 63A rcd main switch and the inverters fed with 4mm twin and earth (6mm sma reccommended i know)

The line voltage is before start up 243v.

When 1 inverter kicks in the voltage on that sunny boy display goes up to 251v.
When the 2nd one kicks in the voltage on both displays goes up to 261v and number 1 drops out and goes into start up.

Now this array is on a barn at the end of a 80 metre 10mm swa from the house.

The Ze is 5.20 ohms on the earth rod (the house is TN-C-S) and 243v at main head(inverters off)

My question is to you the legend that is Big Solar or similar clever PV dudes, Would the volt drop on the cable affect the voltage rise?

And if i upgraded the 80m swa run to 16mm would this reduce this over voltage rise that affects both inverters?

 

[Jeffo]

I've installed 2 4000TL's and both times the protection settings were incorrect the under voltage was set to 180 something volts and the over frequency was set to 51.5 Hz, Iv'e contacted SMA and am awaiting a reply. I set the dials correctly and then set sunny explorer to the correct country setting too with the same result. Has anyone else had this problem?

 

[SolarCity]

Ok I have 2 4000 TL's separately fed with 2 16A mcb's from a 2 way ccu 63A rcd main switch and the inverters fed with 4mm twin and earth (6mm sma reccommended i know)

The line voltage is before start up 243v.

When 1 inverter kicks in the voltage on that sunny boy display goes up to 251v.
When the 2nd one kicks in the voltage on both displays goes up to 261v and number 1 drops out and goes into start up.

Now this array is on a barn at the end of a 80 metre 10mm swa from the house.

The Ze is 5.20 ohms on the earth rod (the house is TN-C-S) and 243v at main head(inverters off)

My question is to you the legend that is Big Solar or similar clever PV dudes, Would the volt drop on the cable affect the voltage rise?

And if i upgraded the 80m swa run to 16mm would this reduce this over voltage rise that affects both inverters?

It does sound like voltage drop is the issue. The inverters will try and produce a voltage which is higher than the grid voltage. Are you measuring 243v at the cut out or at your inverter? If you are measuring it at your inverter then there is a good chance that the voltage at the cut out will be somewhat higher because of the volt drop in the cable. So, for example, the grid voltage may be 248v. The inverter will then need to produce a voltage that is higher than 248v yet still allow for the volt drop. It therefore has to produce at 254v (again, for example) to produce a voltage at the cut out which is higher than the 248v of the grid (allowing for the volt drop). The inverter will only allow 253v before it cuts out (although recent developments seem to suggest that this has been relaxed somewhat) and this is what sounds like is happening in your system. Upgrading the cable is perhaps the only (and expensive) option.

To be fair, it is not a concept that I fully understand and I believe it was BruceB who explained it to me so hopefully he'll be able to help you out more.

 

[BruceB]

Bluntly, the design is poor.
- 16A mcbs are small for a 4000TL
- rcd main switch is not wise unless 200mA or more (ie 2 x 100mA because x2 inverters)
- 80m 10mm2 SWA is undersized
- 4mm2 is undersized unless very short

Assume both inverters were pushing out 16A, then the VD in the 80m SWA cable would be 12.5V (using TLC calculator). That ties in with your numbers, because your first inverter causes a voltage rise of 8V measured at the inverter. That will be 12.5/2 plus 1.75V from voltage drops in other cables in the installation and from the DNO's cable back to the transformer. That is way outside the 1% you are meant to be designing to on the ac side.

Biggs, you might be right that some inverters are set to cut out at 253V, but that is wrong in this country. The max voltage for the delivered mains at the service head here is 253V. The G83 limit for inverters to cut out in this country is 264V.

Fiador might just get away with the inverters operating at 261V if they are both set up right, but the smallest mains glitch would trip them.

Again using the TLC calculator, it looks like increasing to 16mm2 cable would give you a 7.42V drop at 32A so you would be 5V better off at the inverters.

Another option is to put the dc down swa cables and have the inverters near the service head.

It needs a proper re-design.

Regards
Bruce

 

[fiardor]

AS always guys you have been amazing and i will adhere to, learn from and implement most of the above (except move the inverters close to the main head as i would then have 80m of d.c to contend with lol).

This is the first job my company has done outside G83 and clearly this needs a lot more thought and designing rather than just doubling a residential 4KW system to 8KW to concur with G59.

Thanks again you two.

Fiardor.

 

[kmcgold]

contact sma get a personal sma grid guard code
you need to connect to the inverter and change the settings to g83 (locks the settings after 10hrs)
speak to dno for a 4kw system you might have to change the freq setting to 51.5 hz and 500ms

 

[kmcgold]

sorry didnt read all the threads

check resistance between l - n if over 1 ohms inverter shuts off
10mm for two inverters under sized if over 80 mtrs
do cable cals

 

[moggy1968]

The language problem is solved by moving a little jumper block inside the inverter. it tells you in the instructions. should have been done on installation. you shouldn't have to change the country settings dial if the inverter is UK spec supplied.

 

[Graeme Harrold]

The jumper block is there to over ride the counry specific settings, If set right on the dials, the language will also be set to suit.

 

[Deleted member 38070]

you'll have to get your installer to change the grid parameters as they will have to obtain a grid guard code to access the grid monitoring values, if its set to (a)5,(b)8 it will be set for uk with g83 compliant settings settings, that said i did have one that thought it was an sb5000tl and was not a happy bunny, so it might be a firmware c**kup, we had one which had to have the upper frequency cutout changed from 50.5 to 51.5 (western power) for this problem too.. bad news when the dno agree to specific values then move the goal posts... :-( when you find out what the problem was post it on here. what size system do you have is it over 3.68KWp?