4.9 kWp Solar Panel Installation: Coping with 253V Voltage Peak on SMA SB 4600 W Inverter

Hello.
I have recently had a photovoltaic installation - 4.9 kWp panels and a single-phase SMA SB 4600 W inverter. After connecting, it turns out that during the peak of energy production, the voltage reaches even 253 V and then the inverter disconnects. I will add that my connection is a 5x16mm? cable (copper) So I do not think that I could improve something more on my part. The voltage in the network is at least 240 V - so normal. During the production it has to be raised, normal, but to do that? on the supplier's side it is an overhead line (I do not know what cross-section, I think it is 32mm? Al) and the distance to the transformer is about 500m. Anyone know what can be improved in such a situation to eliminate this problem?

I'm surprised you opted for such power in one phase. I have 4.5 kW and similar problems. What is your wire size from the inverter to the meter?

1. Change the inverter settings.
2. Switch to another phase.
3. Load the phase on which the inverter is located, eg with a heater
4. As the inverter does not change to another country, the inverter is replaced.
5. Decompose the installation into 2 phases.
6 Report overvoltage goes to lower voltage.
Write what inverter you have.

Connection as I wrote - 16mm?, and 10mm? to the inverter

Added after 6 [minutes]:

1. Change the inverter settings.
2. Switch to another phase.
3. Load the phase on which the inverter is located, eg with a heater
4. As the inverter does not change to another country, the inverter is replaced.
5. Decompose the installation into 2 phases.
6 Report overvoltage goes to lower voltage.
Write what inverter you have.


1.Turns off at 253V so according to the standards.
2. They all have the same tension.
3.No sense.
4. See 1.
5.Single phase inverter.
6. The most sensible, but will the network operator be interested in such a small fence?
SMS inverter SB 4600 TL

As for point 1 you can set to a different standard and it will turn off at higher voltages. For me it is about 260V. The most sensible thing is to get along with the operator about lowering the voltage, but somehow I don't believe it.

DANIELijuz wrote:

Connection as I wrote - 16mm2, while to the inverter 10mm2

Added after 6 [minutes]:



1. Shuts down at 253v so according to standards.
2. They all have the same tension.
3.No sense.
4. See 1.
5.Single phase inverter.
6. The most sensible, but will the network operator be interested in such a small fence?
SMS inverter sb 4600 TL

Measure these voltages at the connection, maybe there is a voltage drop at the connections.
point 2- nevertheless test on the others, the stiffness of the tension is also important, i.e. how much it will rise on each phase.
Not necessarily the lowest voltage will be the best for the correct operation of the inverter.

Connecting heaters or other loads helps. In the long run, change the country and thus the tension through the Guard Code. Then you risk damaging the equipment of other customers on this transformer.

Jan_Werbinski wrote:

Then you risk damaging the equipment of other customers on this transformer.

May I have a further explanation of why?

253V is the maximum voltage that complies with the standard. The neighbor's household appliances that you burn by increasing the voltage on your street to 253V will be faulty and he is to repair it at his own expense. If you burn them at 260V and prove it to you, theoretically you have to cover all the damage.
I had a similar problem before changing the settings of the inverters. In the afternoon they turned off with the message of too high AC voltage. It was ad hoc to turn on the boiler and washing. Another reason was a drop by a few V due to makeshift and poor contacts - I changed the cable to the PV switchboard to 5x4mm2 and improved the connections, which eliminated the voltage drop. Finally, I changed the standard to EN50438 (no. From memory), the voltage ranges of which were greater than the country where the inverters came from.
Some people change to Germany and then the upper voltage is probably 260V. Get a Guard Code from SMA and you can change it at your own risk. You have to tell them you're an electrician.

What is the distance of the inverter from the meter? I had a similar problem, because I installed an inverter next to the panels, several meters from the meter. As a result of the existing resistance and voltage drop on the wires (and possibly poor contacts) there was a voltage difference of a few volts at the meter and the inverter, as a result of which the inverter tried to "catch up" with the voltage, it threw out after exceeding 253V. The problem disappeared after moving the inverter just beyond the meter. There was another one that I also dealt with, but that's a different topic.

wiekam1 wrote:

There was another one that I also dealt with, but that's a different topic.

Can a colleague develop a thought? It sounds interesting

A difference of a few volts over a dozen meters precludes the correctness of the installation.

Frog_Qmak wrote:

wiekam1 wrote:

There was another one that I also dealt with, but that's a different topic.

Can a colleague develop a thought? It sounds interesting

As the inverter was "more rigidly" connected to the network, it began to react to sudden load changes (it is about switching the 2 kW boiler heater on and off) and off. Changing the boiler power phase helped, because earlier the inverter was on the same phase.

Today I have a bad day, the SOLON model Satis 30/750 inverter has failed after 3 years and only displays the message "STS foul PIC". Probably a small chance, but maybe someone had to deal with this type and accident?

Added after 6 [minutes]:

Jan_Werbinski wrote:

A difference of a few volts over a dozen meters precludes the correctness of the installation.

Exactly, this was the case I had to deal with. I also noticed that the inverter itself shows a slightly higher voltage (in relation to the meter, assuming, of course, that it measures well) than it does, and I assumed that maybe a standard "overlap" is taken to make it within the accepted standard.

Hello
I show up here with another problem, my connection is at the very end of the transformer thread and I have very high voltage drops sometimes on one phase, sometimes on the other and for this reason the inverter turns off the photos from the application from the inverter please give a hint for which country what standard switch the inverter so that the inverter shutdown voltage is lower.
The inverter is SOFAR 6.6KTL-X

best regards
Sebastian

You can see a problem mainly with the S phase, the voltage drops below 190V and this is more than the permissible +/- 10% and I think that changing the country will not help here because the other phases are normal, then you would have to report to the operator by presenting photos with voltage indications from their own meter because that might be more convincing

Perhaps the problem would be solved by replacing it with an Elnix inverter and setting the lower operating voltage to 180V in the installer menu.

MichałS wrote:

Perhaps the problem would be solved by replacing it with an Elnix inverter and setting the lower operating voltage to 180V in the installer menu.

If you had too little air in one wheel, you would deflate the other three to improve - a brilliant idea, especially with this Elnix crap.

You have to report the problem to the operator and they will act correctly, increasing the voltage.

But the "blemish" found up to 184V inverter should work normally.

You went for advice, if you have a problem with the network, do not report it to the operator, just replace the inverter for a few thousand, brilliant.