GEN24, Tauro and Verto Country Setup Menu Operating Instructions

The "Country Setup" menu area is intended exclusively for installers/service technicians from authorised specialist companies. To request the access code required for this menu area, see chapter Requesting inverter codes in Solar.SOS.

The selected country setup for the respective country contains preset parameters according to the nationally applicable standards and requirements. Depending on local grid conditions and the specifications of the energy provider, adjustments to the selected country setup may be necessary.

1. General

The "Country Setup" menu area is intended exclusively for installers/service technicians from authorised specialist companies. To request the access code required for this menu area, see chapter Requesting inverter codes in Solar.SOS.

The selected country setup for the respective country contains preset parameters according to the nationally applicable standards and requirements. Depending on local grid conditions and the specifications of the energy provider, adjustments to the selected country setup may be necessary.

1. General

The "Country Setup" menu area is intended exclusively for installers/service technicians from authorised specialist companies. The inverter access code required for this menu area can be requested in the Fronius Solar.SOS portal.

Requesting inverter codes in Solar.SOS:

1.

Go to solar-sos.fronius.com in a browser

2.

Log in with your Fronius account

3.

On the top right, click on the drop-down menu   

4.

Select the menu item Show inverter codes

5.

A contract page appears on which the request for the access code to change the grid parameters for Fronius inverters is located

6.

Accept the Terms of use by checking Yes, I have read and agree to the terms of use and click Confirm & Save

7.

After that, the codes can be retrieved in the drop-down menu at the top right under Show inverter codes

1Go to solar-sos.fronius.com in a browser

2Log in with your Fronius account

3On the top right, click on the drop-down menu   

4Select the menu item Show inverter codes

✓A contract page appears on which the request for the access code to change the grid parameters for Fronius inverters is located

5Accept the Terms of use by checking Yes, I have read and agree to the terms of use and click Confirm & Save

6After that, the codes can be retrieved in the drop-down menu at the top right under Show inverter codes

1. General

The "Fronius Solar.start" app is needed for registration. Depending on the end device, the app is available on the respective platform.

1Start the installation in the app.

2Select the product to which the connection should be established.

3Open the access point by touching the sensor once    → Communication LED: flashes blue.

4Select the "Technician" user in the "User menu" and enter and confirm the password for the "Technician" user.

5Call up the "Safety and grid regulations" → "Country setup" menu area.

6Enter the requested access code (see chapter Requesting inverter codes in Solar.SOS on page (→)) in the input field "Access code country setup" and click the button "Activate".

7Adjust the parameters in the individual menu areas taking into account the nationally applicable standards and/or the specifications of the energy provider.

1. General

WLAN:

1Open the access point by touching the sensor once    → Communication LED: flashes blue.

2Establish the connection to the inverter in the network settings (the inverter is displayed with the name "FRONIUS_PILOT" and the serial number of the device).

3Password: enter 12345678 and confirm.
IMPORTANT!
To enter the password on a Windows 10 operating system, the link "Connect using a security key instead" must first be activated to establish a connection with the password: 12345678.

4In the browser address bar, enter and confirm the IP address 192.168.250.181.

5Select the "Technician" user in the "User menu" and enter and confirm the password for the "Technician" user.

6Call up the "Safety and grid regulations" → "Country setup" menu area.

7Enter the requested access code (see chapter Requesting inverter codes in Solar.SOS on page (→)) in the input field "Access code country setup" and click the button "Activate".

8Adjust the parameters in the individual menu areas taking into account the nationally applicable standards and/or the specifications of the grid operator.

Ethernet:

1Establish a connection to the inverter (LAN1) with a network cable (CAT5 STP or higher).

2Open the access point by touching the sensor once    → Communication LED: flashes blue.

3In the browser address bar, enter and confirm IP address 169.254.0.180.

4Select the "Technician" user in the "User menu" and enter and confirm the password for the "Technician" user.

5Call up the "Safety and grid regulations" → "Country setup" menu area.

6Enter the requested access code (see chapter Requesting inverter codes in Solar.SOS on page (→)) in the input field "Access code country setup" and click the button "Activate".

7Adjust the parameters in the individual menu areas taking into account the nationally applicable standards and/or the specifications of the grid operator.

Predefined setups can be selected in the "Country setup selection" menu. The selected country setup for the respective country contains preset parameters according to the nationally applicable standards and requirements. Depending on local grid conditions and the specifications of the energy provider, adjustments to the selected country setup may be necessary.

1. Country setup

Predefined setups can be selected in the "Country setup selection" menu. The selected country setup for the respective country contains preset parameters according to the nationally applicable standards and requirements. Depending on local grid conditions and the specifications of the energy provider, adjustments to the selected country setup may be necessary.

1. Country setup
2. Country setup selection

Predefined setups can be selected in the "Country setup selection" menu. The selected country setup for the respective country contains preset parameters according to the nationally applicable standards and requirements. Depending on local grid conditions and the specifications of the energy provider, adjustments to the selected country setup may be necessary.

1. Country setup

These parameters can be used to set the grid monitoring times before the inverter is switched on.

• The permissible range for the mains voltage is defined in the menu area "Grid and system protection" → "Voltage" → "Startup and reconnection" (see chapter Voltage).
• The permissible range for the grid frequency is defined in the menu area "Grid and system protection " → " Frequency " → " Startup and reconnection" (see chapter Frequency).

1. Country setup
2. General

These parameters can be used to set the grid monitoring times before the inverter is switched on.

• The permissible range for the mains voltage is defined in the menu area "Grid and system protection" → "Voltage" → "Startup and reconnection" (see chapter Voltage).
• The permissible range for the grid frequency is defined in the menu area "Grid and system protection " → " Frequency " → " Startup and reconnection" (see chapter Frequency).

1. Country setup
2. General

Ramp rates limit the maximum rate of change of effective power in special situations. Rising ramps ("Ramp-Up") limit the increase in effective power at the inverter AC output. Falling ramps ("Ramp-Down") limit the reduction of effective power at the AC output of the inverter.

Note that the lowest rate of change is applied if there are multiple rate of change specifications. An "Irradiation Ramp" can thus be rendered ineffective by, for example, a lower "Startup Ramp" or another function affecting the rate of change (e. g., P(U) or P(F)).

"Ramp-Up at Startup and Reconnection"
When connecting the inverter, the maximum rate of change of the effective power can be limited by a rising ramp with a defined gradient. As soon as the effective power increase is influenced due to the available PV power or another control, the ramp is terminated.

"Ramp-Up/Down Irradiation"
The "Irradiation Ramp" is a permanent limitation of the rate of change for the effective power. If the PV power changes rapidly due to passing clouds, the rate of change of the inverter output power is limited with the "Ramp-Up Irradiation Rate" or the "Ramp-Down Irradiation Rate".

Example: Effective power limitation by "Irradiation-Ramp-Up/Down", which was caused by a change in the available PV power.

"Ramp-Up/Down Communication"
This is a limitation of the effective power rate of change when changing external specifications for effective power. These can be, for example, power limitations via I/Os or Modbus commands. If smaller rates of change are specified via Modbus command, these are applied. Larger rates are limited by the parameter "Ramp-Up Communication Rate" or "Ramp-Down Communication Rate".

1. Country setup

Unintentional islanding
In the event of a grid failure or disconnection of a small part of the grid from the higher-level utility grid, it is possible under special conditions for local loads and inverters to establish unintentional islanding. If the generation and load (of both active and reactive power) are balanced, the AC voltage and frequency can remain within the allowable limits. In this case, the inverter (without additional islanding detection) will continue feeding energy into the grid, will not automatically shut down, and will supply power to the local loads. This is an unwanted condition. To prevent these situations, active or passive islanding detection methods can be used.

Active islanding detection
The inverter's active islanding detection function detects unwanted islanding situations, the inverter stops feeding energy into the grid and disconnects from the AC grid at all poles.
The detection process is carried out using a grid frequency shift method (Active Frequency Drift): In the event of short-term grid frequency changes, the inverter feeds in an alternating current with a changed frequency (frequency shift). In the event of an interruption to the grid, the AC voltage will also change its frequency. There is a co-feedback effect, whereby the frequency is shifted so much that it exceeds or falls below the permissible limits. This causes the inverter to stop feeding energy into the grid.
In the case of three-phase inverters, the method is also able to detect islanding on any individual phases. This function is an active islanding detection method, since the inverter specifically changes its feed-in behaviour during the detection process.

In contrast, there are passive methods that detect islanding based only on the measurement of AC network variables. This group includes, for example, "Rate of Change of Frequency (RoCoF) Protection".

1. Country setup
2. Safety

Unintentional islanding
In the event of a grid failure or disconnection of a small part of the grid from the higher-level utility grid, it is possible under special conditions for local loads and inverters to establish unintentional islanding. If the generation and load (of both active and reactive power) are balanced, the AC voltage and frequency can remain within the allowable limits. In this case, the inverter (without additional islanding detection) will continue feeding energy into the grid, will not automatically shut down, and will supply power to the local loads. This is an unwanted condition. To prevent these situations, active or passive islanding detection methods can be used.

Active islanding detection
The inverter's active islanding detection function detects unwanted islanding situations, the inverter stops feeding energy into the grid and disconnects from the AC grid at all poles.
The detection process is carried out using a grid frequency shift method (Active Frequency Drift): In the event of short-term grid frequency changes, the inverter feeds in an alternating current with a changed frequency (frequency shift). In the event of an interruption to the grid, the AC voltage will also change its frequency. There is a co-feedback effect, whereby the frequency is shifted so much that it exceeds or falls below the permissible limits. This causes the inverter to stop feeding energy into the grid.
In the case of three-phase inverters, the method is also able to detect islanding on any individual phases. This function is an active islanding detection method, since the inverter specifically changes its feed-in behaviour during the detection process.

In contrast, there are passive methods that detect islanding based only on the measurement of AC network variables. This group includes, for example, "Rate of Change of Frequency (RoCoF) Protection".

1. Country setup
2. Safety

Isolation monitoring ("Iso Monitoring")
The inverter performs an isolation measurement at the DC terminals of the PV generator before each connection (at least once a day). Isolation monitoring must be activated for both the isolation warning and the isolation error.

Isolation Warning
The measured value of the isolation monitoring is used for an isolation warning. Status code 1083 is displayed if the measured value falls below an adjustable limit value.

Isolation Error
The measured value of the isolation monitoring is also used for isolation error monitoring. If the measured isolation value is below the limit value "Isolation Error Threshold", feeding energy into the grid is prevented and status code 1082 is displayed.

1. Country setup
2. Safety

These parameters can be used to set the behaviour of the arc detection at the DC terminals of the inverter. The DC Arc Fault Protection function protects against arc faults and contact faults. Any faults that occur in the current and voltage curve are constantly evaluated and the current circuit is switched off if a contact fault is detected. This prevents overheating on defective contacts and possible fires.

1. Country setup
2. Safety

The inverter is equipped with a universal current-sensitive residual current monitoring unit (RCMU) in accordance with IEC 62109-2. This unit monitors residual currents from the PV module to the AC output of the inverter and disconnects the inverter from the grid in the event of unauthorised residual current.

1. Country setup
2. Safety

Devices for shutdown within the DC generator (e.g. in or on the module or within a string) can be controlled by the inverter. The condition for this is compatibility, especially with the communication of the inverter.

1. Country setup

This chapter deals with the protection settings for overvoltage and undervoltage. Mains voltage limits are defined for this purpose. These depend on the country setup and can be adjusted as described below.

• an undervoltage with associated protection time, or
• an overvoltage with associated protection time.

The protection time describes the duration for which the voltage may be outside the respective voltage limit value before the inverter switches off with an error message.
Three overvoltage and three undervoltage limit values can be used. The "Inner Limits" (U< for undervoltage; U>for overvoltage) refer to those limit values which are closer to the nominal voltage. The "Middle Limits" (U< for undervoltage; U>for overvoltage) have a greater distance to the nominal voltage. The greatest distance between the nominal voltage and the limit value is for the "Outer Limits" (U<< for undervoltage; U>> for overvoltage).
For expedient use of the "Inner Limits" and "Outer Limits", the respective "Inner Limit" must be linked to a greater time than the "Outer Limit". If the "Middle Limits" are also used, their time between "Inner Limit" and "Outer Limit" must be set, see example in the diagram.

Graphic illustrating the limits

IL	"Inner limit" - inner limit value
ML	"Middle Limit" - middle limit value
OL	"Outer limit" - outer limit value
(1)	Trip range
OV	Overvoltage
UV	Undervoltage
tx	Protection time

These voltage limit values are not active in backup power mode. Under "Device configuration" → " Inverter" → "Backup power", the voltage limits that apply in backup power mode can be configured.

"Inner Limits"

"Middle Limits"

"Outer Limits"

"Long Time Average Limit"
This function calculates a moving average voltage value over the set time and compares it with the set overvoltage protection value. If the overvoltage protection value is exceeded, a disconnect occurs.

"Fast Overvoltage Disconnect"
Fast overvoltage disconnect for voltage spikes that can respond within one period.

"Startup and Reconnection"
Before the inverter is allowed to connect, the connection conditions for voltage and frequency must be fulfilled for a certain time.

A distinction is made between:

• "Startup": switching on the inverter during a normal startup process (e. g. at sunrise) and
• "Reconnection": the reconnection of the inverter after a grid fault (see table "Grid faults") (e. g. if a fault occurs in the AC grid during the day which causes the inverter to disconnect).

Which limit values are used when checking the connection conditions depends on whether a mains fault has occurred and which "Mode" is defined. The "Mode" only influences the limit values and not the monitoring time. The monitoring time is determined by the parameters described in "General" / "Startup and Reconnection". The monitoring time used depends on whether it is "Startup" or "Reconnection" and applies equally to frequency and voltage limits. After the grid monitoring has expired, the previously mentioned "Interface Protection" values are active. In backup power mode these "Startup and Reconnection" parameters are not active.

1. Country setup
2. Interface Protection

This chapter deals with the protection settings for overvoltage and undervoltage. Mains voltage limits are defined for this purpose. These depend on the country setup and can be adjusted as described below.

• an undervoltage with associated protection time, or
• an overvoltage with associated protection time.

The protection time describes the duration for which the voltage may be outside the respective voltage limit value before the inverter switches off with an error message.
Three overvoltage and three undervoltage limit values can be used. The "Inner Limits" (U< for undervoltage; U>for overvoltage) refer to those limit values which are closer to the nominal voltage. The "Middle Limits" (U< for undervoltage; U>for overvoltage) have a greater distance to the nominal voltage. The greatest distance between the nominal voltage and the limit value is for the "Outer Limits" (U<< for undervoltage; U>> for overvoltage).
For expedient use of the "Inner Limits" and "Outer Limits", the respective "Inner Limit" must be linked to a greater time than the "Outer Limit". If the "Middle Limits" are also used, their time between "Inner Limit" and "Outer Limit" must be set, see example in the diagram.

Graphic illustrating the limits

IL	"Inner limit" - inner limit value
ML	"Middle Limit" - middle limit value
OL	"Outer limit" - outer limit value
(1)	Trip range
OV	Overvoltage
UV	Undervoltage
tx	Protection time

These voltage limit values are not active in backup power mode. Under "Device configuration" → " Inverter" → "Backup power", the voltage limits that apply in backup power mode can be configured.

"Inner Limits"

"Middle Limits"

"Outer Limits"

"Long Time Average Limit"
This function calculates a moving average voltage value over the set time and compares it with the set overvoltage protection value. If the overvoltage protection value is exceeded, a disconnect occurs.

"Fast Overvoltage Disconnect"
Fast overvoltage disconnect for voltage spikes that can respond within one period.

"Startup and Reconnection"
Before the inverter is allowed to connect, the connection conditions for voltage and frequency must be fulfilled for a certain time.

A distinction is made between:

• "Startup": switching on the inverter during a normal startup process (e. g. at sunrise) and
• "Reconnection": the reconnection of the inverter after a grid fault (see table "Grid faults") (e. g. if a fault occurs in the AC grid during the day which causes the inverter to disconnect).

Which limit values are used when checking the connection conditions depends on whether a mains fault has occurred and which "Mode" is defined. The "Mode" only influences the limit values and not the monitoring time. The monitoring time is determined by the parameters described in "General" / "Startup and Reconnection". The monitoring time used depends on whether it is "Startup" or "Reconnection" and applies equally to frequency and voltage limits. After the grid monitoring has expired, the previously mentioned "Interface Protection" values are active. In backup power mode these "Startup and Reconnection" parameters are not active.

1. Country setup
2. Interface Protection

This chapter deals with the protection settings for overfrequencies and underfrequencies. Grid frequency limit values are defined for this purpose. These depend on the country setup and can be adjusted as described below.

• an underfrequency with associated protection time, or
• an overfrequency with associated protection time.

The protection time describes the duration for which the frequency may be outside the respective frequency limit value before the inverter switches off with an error message. Two overfrequency and two underfrequency limit values can be used. The "Inner Limits" (f< for underfrequency; f>for overfrequency) are those limit values which are closer to the rated frequency than the "Outer Limits" (f<< for underfrequency; f>> for overfrequency). For the sensible use of both ranges, the respective "Inner Limit" must be linked to a larger time than the "Outer Limit".

Graphic illustrating the limits

IL	"Inner limit" - inner limit value
OL	"Outer limit" - outer limit value
(1)	Trip range
OF	Overfrequency
UF	Underfrequency

In backup power mode, the inverter itself determines the frequency and the frequency limits are therefore not active.

"Inner Limits"

"Outer Limits"

"Alternative Limits"
For the inner frequency limit values there is an additional second parameter set, which is only relevant for Italy. In order to activate this second parameter set, the alternative frequency limit value must be set to "On" on the user interface of the inverter and activated/deactivated via an external signal as follows:

• Activate: http://<IP>/status/SetSignaleEsterno
• Deactivate: http://<IP>/status/ClearSignaleEsterno

Each time the inverter is restarted, the "Frequency Alternative Limit" does not have to be set to "On" again, but the external signal to activate it must be sent again. If it is not sent, the inner frequency limit value is used.

"Startup and Reconnection"
Before the inverter is allowed to connect, the connection conditions for voltage and frequency must be fulfilled for a certain time.

A distinction is made between:

• "Startup": switching on the inverter during a normal startup process (e. g. at sunrise) and
• "Reconnection": the reconnection of the inverter after a grid fault (see table "Grid faults") (e. g. if a fault occurs in the AC grid during the day which causes the inverter to disconnect).

Which limit values are used when checking the connection conditions depends on whether a mains fault has occurred and which "Mode" is defined. The "Mode" only influences the limit values and not the monitoring time. The monitoring time is determined by the parameters described in "General" / "Startup and Reconnection". The monitoring time used depends on whether it is "Startup" or "Reconnection" and applies equally to frequency and voltage limits. After the grid monitoring has expired, the previously mentioned "Interface Protection" values are active. In backup power mode these "Startup and Reconnection" parameters are not active.

"Rate of Change of Frequency (RoCoF) Protection"
This function allows the RoCoF (Rate of Change of Frequency) ‑detection and ‑switch-off to be activated and adjusted. In the event of frequency changes that are above a set value and last longer than the set time, the inverter is shut down. RoCoF detection can be used as a passive stand-alone operation detection method.

1. Country setup
2. Interface Protection

DC injection means the injection of an AC current into the public grid that is unintentionally contaminated with a DC component. This DC component causes a shift of the pure AC current on the Y-axis (offset).
Due to the way the inverter works, no DC injection takes place in normal operation. However, in order to be protected against faults or inaccuracies, many connection rules require monitoring of the DC injection and shutdown if limit values are exceeded.
Internal and external limits can be defined for the limit values. Inner limits have tighter limits and longer protection times by default, outer limits have broader limits and shorter protection times, so that shutdown occurs more quickly with higher DC components. For both limit values there is a protection time which defines the maximum overshoot duration.

"Inner Limit"

"Outer Limit"

1. Country setup

In the event of faults in the grid, there is a risk of a large number of generation plants being shut down unintentionally and thus a risk of network collapse. Grid voltage disturbances (Voltage Fault, Gridvoltage-Disturbance) are short-term voltage dips or surges in the grid. These voltage changes go beyond the normal range of the operating voltage (e.g. nominal voltage +/- 10 %). However, the duration of the voltage changes is short, so that the normal operating voltage is reached again before the system is shut down (due to "Interface Protection"). Voltage Fault Ride Through means that the inverter can ride through such a grid voltage fault without shutting down prematurely. If the shutdown conditions of the protection settings ("Grid and system protection" or "Interface Protection") are reached (time and value), the inverter always shuts down, thus terminating VFRT operation. The requirements for the exact behaviour of the inverters during the fault depend on the respective grid connection rules. The following parameters determine this behaviour.

Classification into regions
The voltage fault detection of the inverter detects severe or rapid mains voltage fluctuations and classifies them into so-called regions according to the level of the fault voltage (voltage level during the fault). Each region is assigned a specific mains voltage value range. Three individual regions (R1, R2, R3) can be configured. Each individual region has an adjustable detection threshold and several parameters that determine the behaviour of the inverter within that region. The detection limit is a relative voltage level and is specified in percent derived from the AC nominal voltage. A value above 100 % means that the associated region describes an overvoltage disturbance (High Voltage Ride Through HVRT). A value less than 100 % means that the associated region describes an undervoltage fault (Low Voltage Ride Through LVRT). Figure 1 shows an example of a typical arrangement of the three regions (shown here with horizontal bars) by selective choice of detection thresholds: R1 threshold 110 %, R2 threshold 90 %, R3 threshold 40 %. The voltage range between the limits of Region1 and Region2 (white bar) comprises the voltage range for normal operation (here: 90 to 110 % of the nominal voltage). Region 1 comprises overvoltage disturbances, Region 2 consists of slight undervoltage disturbances (from 90 to 40 %). Region 3 consists of severe undervoltage disturbances (below 40 %).

Division of the grid voltage range into three fault regions by selecting the detection thresholds.

IMPORTANT!
The length of the bars represents trip times for overvoltage and undervoltage detection of the "Interface Protection" function group. This has no significance for the VFRT functionality.

• The R1 threshold must be higher than the R2 threshold, and so on.
• The use of identical thresholds for multiple regions is prohibited.
• Using the threshold value 0 % is allowed.

To deactivate a specific region, its threshold can be used:
An HV region (R1) is deactivated by adjusting the threshold to 200 %. An unused LV region (usually R3) is deactivated by adjusting the threshold to 0 %.

General VFRT settings
The following setting values apply equally to all regions.

Region 1
These setting values define how the inverter behaves within Region 1. The choice of setting has no effect on regions 2 and 3.

Region 2
These setting values define how the inverter behaves within Region 2. The choice of setting has no effect on regions 1 and 3.

Region 3
These setting values define how the inverter behaves within Region 3. The choice of setting has no effect on regions 1 and 2.

1. Country setup
2. Grid Support Functions

In the event of faults in the grid, there is a risk of a large number of generation plants being shut down unintentionally and thus a risk of network collapse. Grid voltage disturbances (Voltage Fault, Gridvoltage-Disturbance) are short-term voltage dips or surges in the grid. These voltage changes go beyond the normal range of the operating voltage (e.g. nominal voltage +/- 10 %). However, the duration of the voltage changes is short, so that the normal operating voltage is reached again before the system is shut down (due to "Interface Protection"). Voltage Fault Ride Through means that the inverter can ride through such a grid voltage fault without shutting down prematurely. If the shutdown conditions of the protection settings ("Grid and system protection" or "Interface Protection") are reached (time and value), the inverter always shuts down, thus terminating VFRT operation. The requirements for the exact behaviour of the inverters during the fault depend on the respective grid connection rules. The following parameters determine this behaviour.

Classification into regions
The voltage fault detection of the inverter detects severe or rapid mains voltage fluctuations and classifies them into so-called regions according to the level of the fault voltage (voltage level during the fault). Each region is assigned a specific mains voltage value range. Three individual regions (R1, R2, R3) can be configured. Each individual region has an adjustable detection threshold and several parameters that determine the behaviour of the inverter within that region. The detection limit is a relative voltage level and is specified in percent derived from the AC nominal voltage. A value above 100 % means that the associated region describes an overvoltage disturbance (High Voltage Ride Through HVRT). A value less than 100 % means that the associated region describes an undervoltage fault (Low Voltage Ride Through LVRT). Figure 1 shows an example of a typical arrangement of the three regions (shown here with horizontal bars) by selective choice of detection thresholds: R1 threshold 110 %, R2 threshold 90 %, R3 threshold 40 %. The voltage range between the limits of Region1 and Region2 (white bar) comprises the voltage range for normal operation (here: 90 to 110 % of the nominal voltage). Region 1 comprises overvoltage disturbances, Region 2 consists of slight undervoltage disturbances (from 90 to 40 %). Region 3 consists of severe undervoltage disturbances (below 40 %).

Division of the grid voltage range into three fault regions by selecting the detection thresholds.

IMPORTANT!
The length of the bars represents trip times for overvoltage and undervoltage detection of the "Interface Protection" function group. This has no significance for the VFRT functionality.

• The R1 threshold must be higher than the R2 threshold, and so on.
• The use of identical thresholds for multiple regions is prohibited.
• Using the threshold value 0 % is allowed.

To deactivate a specific region, its threshold can be used:
An HV region (R1) is deactivated by adjusting the threshold to 200 %. An unused LV region (usually R3) is deactivated by adjusting the threshold to 0 %.

General VFRT settings
The following setting values apply equally to all regions.

Region 1
These setting values define how the inverter behaves within Region 1. The choice of setting has no effect on regions 2 and 3.

Region 2
These setting values define how the inverter behaves within Region 2. The choice of setting has no effect on regions 1 and 3.

Region 3
These setting values define how the inverter behaves within Region 3. The choice of setting has no effect on regions 1 and 2.

1. Country setup
2. Grid Support Functions

Voltage-dependent Power Control
or also called Volt/Watt function or P(U) function, causes a change in effective power depending on the mains voltage. By reducing the effective power at high mains voltage (or increasing the effective power at low mains voltage), an unintentional switch-off of the inverter due to the overvoltage or undervoltage limits can be avoided. This makes the yield losses less than they would be if the inverter was switched off.

• is reduced according to a defined gradient if the mains voltage is too high (see example "System without storage" - red characteristic curve)
• is increased according to a defined gradient if the mains voltage is too low (only possible with hybrid inverters, see example "System with storage" - green characteristic curve).

• If the output power has already been reduced to 0 W when the voltage is too high and the voltage continues to rise, additional energy can be taken from the national grid (the battery is thus charged, see "System with storage and active grid support enabled" - blue characteristic curve in the lower "Power Input" area).
• If the charging power (drawn from the national grid) has been reduced to 0 W when the voltage is too low and the voltage continues to drop, additional energy can be drawn from the battery to increase the output power (see example "System with storage and active grid support enabled" - blue characteristic curve in the upper "Power Output" area).

Examples of active grid support:

General power curve depending on grid voltage.

• "Battery SoC Lower Limit" - The battery will not be further discharged when the lower limit is reached.
• "Battery SoC Upper Limit" - The battery will not be further charged when the upper limit is reached.

Power curve when "Activation Threshold Overvoltage" is exceeded.

Charge power limitation when "Activation Threshold Undervoltage" is exceeded.

• Overfrequency
• Underfrequency

• is reduced according to a defined gradient in the event of an overfrequency (in the case of an inverter with an energy storage device, discharge of the storage device is stopped first before the power of the PV generator is reduced).
• is increased in the event of underfrequency in accordance with a defined gradient (in the case of an inverter without an energy storage device or with active grid support deactivated, only possible in conjunction with a manual power reduction and corresponding priority).

• "Gradient": The gradient is given in %/Hz in relation to the device nominal power or the momentary power when entering the function (see example 1).
• "Stop Frequency": With this method, the gradient always results from the current power at entry to the function to the stop frequency set in the setup and power at stop frequency (see example 2).

• If the output power has already been reduced to 0 W at overfrequency and the frequency continues to rise, additional energy can be drawn from the grid (the battery is thus charged).
• If the charging power (drawn from the grid) is reduced to 0 W at underfrequency and the frequency continues to drop, additional energy can be drawn from the battery to increase the output power.

• "Battery SoC Lower Limit" - The battery will not be further discharged when the lower limit is reached.
• "Battery SoC Upper Limit" - The battery will not be further charged when the upper limit is reached.

• Mode: "On (without Hysteresis)"
  The inverter increases the power from the current reduced value to the original value in accordance with the same gradient used for power reduction.
• Mode: "On (with Hysteresis)"
  The inverter will not increase the power to the original value until the frequency is back in the target value range for a specific length of time.

General power curve with overfrequency and underfrequency without hysteresis with gradients.

General power curve with overfrequency and underfrequency without hysteresis with stop frequency.

General power curve with overfrequency and underfrequency with hysteresis with gradients.

Overfrequency

Power curve at overfrequency with hysteresis.

Underfrequency

Power curve at underfrequency with hysteresis.

General - Frequency-dependent Power Control

Application example with "Return Gradient 1 Alternative" and "Return Gradient 1 Alternative Threshold".

Application example with "Return Gradient 2 Mode".

Battery SoC Limitation for Grid Support

General - Active Power

1. Country setup
2. Grid Support Functions

The voltage in the national grid can be influenced by the controlled use of reactive power by the inverter. When using reactive power control, the effective power generated at the same time is not affected or is only affected to a small extent.

IMPORTANT!
The exchange of reactive power (in addition to the feed-in of effective power) increases the current by the factor 1/cos φ.

• In over-excited mode or capacitive mode, reactive power is supplied to the national grid. This increases the mains voltage.
• In under-excited mode or inductive mode, reactive power is taken from the inverter. The mains voltage is lowered as a result.

• Primo GEN24: Q_max = 60 % of S_n (or cos φ = 0.80 at S_n)
• Symo GEN24: Q_max = 71 % of S_n (or cos φ = 0.70 at S_n)
• Tauro: Q_max = 100 % of S_n (or cos φ = 0.00)
• Verto: Q_max = 100 % of S_n (or cos φ = 0.00)

The value range specified for the following parameters may be additionally limited by the selected country-specific settings.
The following figure shows the possible operating range of the inverter. All valid operating points defined by effective power P and reactive power Q are within the grey area.

Example: Primo GEN24

General settings

Depending on the selected mode, only the setting options in the respective subchapter and these general settings have an effect.

const cos φ
Reactive power default defined by a constant cos φ. The function is limited by the maximum apparent power and Cos φ minimum, the P/Q priority has no effect.

Q Absolute - Constant Reactive Power
Reactive power specification defined by a constant value [Var]. The function is limited by the maximum apparent power and by "Cos φ Minimum"

Q Relative - Constant Reactive Power
Reactive power specification defined by a constant value in percent [%], related to the nominal apparent power (S_n) of the inverter. The function is limited by the maximum apparent power and by "Cos φ Minimum".

Cos φ(P) - Power dependent Power Factor Characteristic
This function controls the cos φ depending on the momentary effective power according to a characteristic curve. The characteristic curve is defined by four data points (1‑2‑3‑4). If fewer data points are required, the identical parameters can be set for two points. The function is limited by the maximum apparent power and by "Cos φ Minimum". For the characteristic curves, the data points must be entered in the X‑axis (effective power) and in the Y‑axis (Cos φ).

Example: Curve defined by four data points.

General
In addition to the four points, the following parameters also come into play:

Q(P) - Power dependent Reactive Power Characteristic
This function controls the reactive power depending on the momentary effective power according to a characteristic curve. The characteristic curve is defined by four data points (1‑2‑3‑4). If fewer data points are required, the identical parameters can be set for two points. The function is limited by the maximum apparent power and by "Cos φ Minimum". For the characteristic curves, the data points in the X‑axis (effective power) and in the Y‑axis (reactive power) must be entered.

Example: Curve defined by four data points.

 In addition to the four points, the following parameters also come into play:

Q(U) - Voltage-dependent Reactive Power Characteristic
This function controls the reactive power as a function of the momentary mains voltage according to a characteristic curve. The characteristic curve is defined by four data points (1‑2‑3‑4). If fewer data points are required, the identical parameters can be set for two points. The function is limited by the maximum apparent power and by "Cos φ Minimum". For the characteristic curves, the data points in the X‑axis (voltage) and in the Y‑axis (reactive power) must be entered.

General
In addition to the four points, the following parameters also come into play:

Shift of the Q(U) characteristic on the Y-axis (Q-axis) via an offset factor.

Example: Curve defined by four data points.

1	U = 95 %, Q = 32 %
2	U = 97 %, Q = 0 %
3	U = 104 %, Q = 0 %
4	U = 105 %, Q = -32 %
(1)	Lock-Out P-Dependent (% of Nominal Apparent Power) = 5 %
(2)	Lock-In P-Dependent (% of Nominal Apparent Power) = 30 %
(3)	Cos φ minimum = 0.9