Photovoltaic Inverter Shutdown During Sunlight: SMA Guard Codes and Parameter Settings

Question

Good morning,
I have a problem with the inverter, namely while the sun is shining due to high voltage in the grid, it turns off and stops working. I've read a bit about the guard codes from SMA, my question is whether with this application and this code you can change any parameter setting of the inverter of different brands and brands? Does anyone have this code? Can anyone recommend someone who provides these services for a fee? Regards.

noja102 · Accepted Answer

You are not allowed to change this NC-RfG grid code. Probably the problem is in the cables on your side (too small cross section or too long distance or both). And there is a lot of PV in the area and what voltage do you have after sunset?

slawo12311 · Accepted Answer

I will join the topic because I am wondering why the inverters turn off instead of trying to limit the output power and thus try to lower the voltage at the output? I understand that the network itself may have too much voltage, but the most likely cause is the inverter and it tries to exceed this voltage itself ...
Maybe there is some manufacturer that used such an algorithm?

noja102 · Accepted Answer

So you have to write to the DSO to lower the voltage in the network Added after 4 [minutes]: No, your inverter beats the neighbor and they raise the voltage to push as much power into the grid and thus kill themselves

noja102 · Accepted Answer

How much would he reduce the power if you have, for example, 10kWp installed and on Sunday afternoon you have the TV, router and fridge turned on? Up to 800W or what? If so, why do you need 10kWp? Do you collect for the winter? DSO asks, you won't collect it because you'll buy a shortage from us anyway, DSO will answer you that way. You thought you were a crook with a few thousand spent in PV, unfortunately we are bigger, OSD will answer you, and what will you do to them, you will cut yourself off from their network, you don't have enough money for complete autonomy, that's all, and OSD knows it perfectly well. Unfortunately, this is how the state protects us from monopoly, because it is their monopoly

Added after 6 [minutes]:

Kcpr98 - maybe a little but how much better to increase auto consumption (overvoltage relay) by 2-3%, and all the time together with the PV holders attached to this transformer torment OSD to lower the voltage

kosmos99 · Accepted Answer

Joke?

gimak · Accepted Answer

No, not tested, but logically it should work. Transformer reducing the voltage e.g. from 260V to 220-230V.

kosmos99 · Accepted Answer

After all, in order to pump energy into the grid, we must have a higher voltage, not lower. If 220V-230V was enough, the inverter would not pick it up. Therefore, 253V, because the supplier provides a phase voltage of 230V with a tolerance of -5 to +10%.

gimak · Accepted Answer

That's right. You wrote it yourself The transformer lowers the voltage, let's say, from 260 V to 230 V and we connect the inverter to this voltage, which tries to maintain such a voltage at the output (higher than 230 V) that will allow the transformer to pump the appropriate power into the grid.

AT PRO · Accepted Answer

But my friend is wrong. In another thread, a friend wrote about it, so I asked about it when replacing the meter. Transformers do not let anything into the medium voltage network. Everything must be consumed within the users connected to a given transformer. Therefore, with a large number of micro-installations in the local network, there is a problem with reception. It remains to either use more or count on lowering the voltage on the transformer, but this can cause problems with voltage drop at low production.

kosmos99 · Accepted Answer

Then why does increasing the voltage help? So as my friend writes: The voltage value should not matter? Since the transformer does not release, and the reception does not increase. Added after 2 [minutes]: But it is the inverter that increases it, it is not so high in the grid. The second thing is that the inverter would give energy through the same transformer, i.e. the voltage would jump again.

sq9fmc · Accepted Answer

Take a look at and forget about the transformer

Jan_Werbinski · Accepted Answer

I have Guard Code and set the appropriate voltages according to the standard so that it cuts off at 253V. Measure what voltage you have on the ZE meter when the inverter cuts off the power supply and what voltage it is when it is already cut off. Do not measure on the inverter, but on the meter!

Szyszkownik Kilkujadek · Accepted Answer

Unfortunately, the only hope is that the power industry will move the tap on the transformer and lower the voltage a bit. You have to band together with your neighbors and flood them with letters. It's about them seeing that something is going on and it's not an isolated incident.
The distribution (energy company) is here between the hammer and the anvil because, on the one hand, they are responsible for the quality of the supplied energy, but on the other hand, they do not supply all the energy.
In the case of a housing estate with a lot of PV, such problems will arise and without systemic solutions, the problem will sprout throughout the country.
I have to be interested in how the Germans deal with it.

gimak · Accepted Answer

But I suppose they are also interested in selling as much of it as possible.

Slawek K. · Accepted Answer

The energy distributor does not sell anything, the Trading company is responsible for this. Distribution's tasks include network and transmission management. Regards

Jan_Werbinski · Accepted Answer

Imported SMA inverters. I had other countries set, with different voltage ranges. I set the standard that applies in Poland and for this I needed the SMA Guard Code. I got from SMA. In those years, they gave it without much fuss. After setting the correct standard, the cut-off voltage was 253V and that's enough for me. In addition, I corrected the diameters of the cables and tightened the loose screws. Why were they loose? Unsolved Mystery.

Jan_Werbinski · Accepted Answer

Three-phase won't help.

fazik · Accepted Answer

It is better to stay with single-phase and load the phase that is connected to the inverter to the maximum.

Szyszkownik Kilkujadek · Accepted Answer

Not better. Because that's not always the case. Or you can simply exceed the protection current. So what then?

sq9fmc · Accepted Answer

You stubbornly try to convince yourself that raising the voltage above the established norms is the way to go, and it is not.
Forget about solving the problem of overvoltage like this.
Someday they'll hang the recorder next door and you'll be the scapegoat.

Kcpr98 · Answer

Yes, there are a lot of PV in the area, after sunset the grid voltage is around 240-250, while the sun is shining it increases even to 265V. The inverter is about 50 meters away from the meter, the wires have a thick vein (I missed it)

Kcpr98 · Answer

It has already been reported to the DSO several times, however, after their visit to the transformer, they claim that everything is within limits and they do not lower the voltage. That's why he's doing something on his own. Would moving the inverter next to the meter stabilize the voltage spikes?

gimak · Answer

Just lower the voltage at home.

Kcpr98 · Answer

Okay, how exactly do you do that? Added after 6 [minutes]: Added after 6 [minutes]: Kcpr98 - maybe a little but how much better to increase auto consumption (overvoltage relay) by 2-3%, and all the time together with the PV holders attached to this transformer torment OSD to lower the voltage Have you or anyone used this overvoltage relay? I understand that I plug it into the circuit and it manages the voltage on a given phase? Will it help?

kosmos99 · Answer

After all, the transformer works both ways and if there are no loads on the low side, it transforms to medium. The problem is with the line impedance. For example: let's assume that the line impedance at the inverter connection point is 1ohm, and you want to feed 10kW to the grid, with no loads on the low side. So the calculated voltage drop is over 13V and the inverter must increase the voltage by that amount in relation to what is on the transformer terminals. The limit for the inverter is 253V and hence the problem.

gimak · Answer

Part of the answer was given by kosnos99. It is enough to install a transformer with the appropriate power and ratio at home.

Kcpr98 · Answer

The exact limit of the inverter is around 253V, I thought to somehow raise this limit parameter, of course, not by several dozen V so as not to burn the neighbor's fridge.

Kcpr98 · Answer

What brand of inverter do you have? Did everything go back to normal after adjusting the voltage? Where did you get the code from?

Kcpr98 · Answer

Thanks to everyone who shared their knowledge on the subject. It remains to harass and wait until the voltage drops or think about a 3-phase inverter. Regards.

[Solved] Photovoltaic Inverter Shutdown During Sunlight: SMA Guard Codes and Parameter Settings

Can I use an SMA Guard Code to change inverter settings from different brands, and how do I stop the inverter from shutting down at high grid voltage?

Topic summary

FAQ

Quick Facts

Why does my photovoltaic inverter shut down around 253 V?

Can I legally raise the cut-off limit using SMA Guard Code or similar?

Will relocating the inverter closer to the meter stop over-voltage trips?

Does a three-phase inverter solve the problem?

Is it true that LV/LV transformers block power flow to the MV grid?

How can I get the DSO to lower voltage?

What role does cable cross-section play?

Could an over-voltage relay (load dump) help?

What is an edge-case failure to watch for?

Are there inverter brands with active power-curtailment algorithms?

How big is the curtailment issue nationally?

Can a household step-down transformer fix high voltage?