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

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.

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?

noja102 wrote:

You are not allowed to change this NC-RfG network 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?

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)

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?

Kcpr98 wrote:

noja102 wrote:

You are not allowed to change this NC-RfG network 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?

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)

So you have to write to the DSO to lower the voltage in the network

Added after 4 [minutes]:

slawo12311 wrote:

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?

No, your inverter beats the neighbor and they raise the voltage to push as much power into the grid and thus kill themselves

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?

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

Kcpr98 wrote:

That's why he's doing something on his own.

Just lower the voltage at home.

gimak wrote:

Kcpr98 wrote:

That's why he's doing something on his own.

Just lower the voltage at home.

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[/quote]

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?

noja102 wrote:

How much would he have to 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?

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.

Kcpr98 wrote:

gimak wrote:
kcpr98 wrote:
That's why he's doing something on his own.

Just lower the voltage at home.

Okay, how exactly do you do that?

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

gimak wrote:

It is enough to install a transformer with the appropriate power and ratio at home.

Joke?

kosmos99 wrote:

noja102 wrote:

How much would he have to 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?

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 more than 13V and the inverter must increase the voltage in relation to what is on the transformer terminals.
The limit for the inverter is 253V and hence the problem.

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.

kosmos99 wrote:

Joke?

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

gimak wrote:

but logic should work. Transformer reducing the voltage e.g. from 260V to 220-230V.

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.

Kcpr98 wrote:

Exactly the limit of the inverter is around 253V

Therefore, 253V, because the supplier provides a phase voltage of 230V with a tolerance of -5 to +10%.

kosmos99 wrote:

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.

That's right. You wrote it yourself

kosmos99 wrote:

After all, a transformer works both ways

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.

kosmos99 wrote:

After all, the transformer works both ways and if there are no loads on the low side, it transforms to medium.

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.

Then why does increasing the voltage help?

So as my friend writes:

AT PRO wrote:

Transformers do not let anything into the medium voltage network.
Everything must be consumed within the users connected to a given transformer.

The voltage value should not matter?
Since the transformer "does not release", and the reception does not increase.

Added after 2 [minutes]:

gimak wrote:

Trafo lowers the voltage, say, from 260 V to 230 V and we connect the inverter to this voltage,

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.

Take a look at https://www.elektroda.pl/rtvforum/topic3621980-30.html#18658532] and forget about the transformer

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!

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.

Szyszkownik Kilkujadek wrote:

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

gimak wrote:

Szyszkownik Kilkujadek wrote:

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

The energy distributor does not sell anything, the Trading company is responsible for this. Distribution's tasks include network and transmission management.
https://www.totalmoney.pl/artykuly/2224,energ...iedzy-dystrybucja-a-dostarczaniem-energii,1,1

Regards

Jan_Werbinski wrote:

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!

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

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.

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.

Three-phase won't help.

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

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

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.