5 LCS tool
5.2.5 Setting Limited Export
Figure 20: LCS-Tool - setting Limited Export
With the Limited Export feature in connection with a
Modbus-capable energy meter, a maximum defined AC
output power can be made available at the grid-connection
point (see figure 22). The total nominal power of all
inverters connected to the Inverter Manager is taken into
account. At the grid-connection point, the inverter's
maximum output power is increased or decreased by the
amount of self-consumption.
The limitation at the grid-connection point is complied with,
while all connected loads can still be supplied with energy
from the inverters.
The maximum setpoint of the nominal PV system power can
be assigned with static or dynamic attributes:
• Assignment of static attributes:
Set the parameter Active Power (P_ref) for the active
power limitation in menu Inverter Parameter under
Protection settings > Support settings >
Immediate controls (see Section 5.2.7 "Changing of
Inverter Parameters", page 28).
• Assignment of dynamic attributes:
In addition, the setpoint of the nominal PV system
power can be limited dynamically via I/O Box,
Modbus and direct marketer interface. If the value is set
dynamically, the parameter Active Power (P_ref) is
overwritten in the LCS-Tool. This applies to both the
regular feed-in operation and to the activated Limited
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Export function. A load-dependent control is not
possible without an activated Limited Export function.
The inverters are then directly limited to the setpoint
(see figure 23).
Procedure:
1. Open the LCS-Tool.
2. Log in as an Installer.
3. Call up the menu Setup.
4. Enter the respective values under Limited Export.
5. Select [Save] to save the changes.
The parameters Meter IP-Address, Meter Modbus Port,
Meter Modbus Unit ID and the register Meter Power
Modbus are used for the configuration of the energy meter.
With zero export as a special case of Limited Export, the
feed-in operation into the utility grid can be completely
prevented. The parameter Safety Offset indicated as
percentage of nominal PV system power is a safety margin
to the maximum value of the output power set at the
grid-connection point.
This safety value is preset for safety reasons and due to
sudden load changes. Thus, a safety margin to the setpoint
is ensured. With the activation process, the setpoint is
reduced to the safety value. Thus, the feed-in power is
always less than the actual setpoint.
SMA Solar Technology AG
Installation Manual