8 Operation
SMA Solar Technology AG
Operating manual
STP8-10-3AV-40-BE-en-12
64
Make the settings for systems with manual setpoint
1. In the tab
Active power mode
set the switch
Grid connection point regulation
to [
On
].
2. Enter the total PV array power in the field
Nominal PV system power
.
3. In the drop-down list
Operating mode active power setting
, select whether active power
limitation is to be performed via a fixed specification in percent or in watts.
4. In the field
Set active power limit
, enter the value to which the active power at the grid-
connection point is to be limited. The value must be set to
0
for zero power output.
5. Set the
Active power setpoint
to [
On
].
6. Select the entry
Manual setpoint in %
or
Manual setpoint in W
for manual specification
and enter the respective setpoint value.
7. If the inverter itself is to control active power at the grid-connection point, perform the following
steps:
• In the drop-down list
Operating mode active power setting
, select the entry
External
setting
.
• In the drop-down list
Fallback behavior
, select the entry
Apply fallback values
.
• In the drop-down list
Grid disconnection for 0% active power setting
select the entry
No
.
8.13 Configuring the Modbus Function
The Modbus interface is deactivated by default and the communication ports 502 set.
In order to access SMA invertes with SMA Modbus
®
or SunSpec
®
Modbus
®
, the Modbus interface
must be activated. After activating the interface, the communication ports of both IP protocols can
be changed. For information on commissioning and configuration of the Modbus interface, see the
technical information "SMA and SunSpec Modbus® Interface" at www.SMA-Solar.com.
For information on which Modbus registers are supported, see the technical information "Modbus®
parameters and measured values" at www.SMA-Solar.com.
Data security during enabled Modbus interface
If you enable the Modbus interface, there is a risk that unauthorized users may access and
manipulate the data or devices in your PV system.
To ensure data security, take appropriate protective measures such as:
• Set up a firewall.
• Close unnecessary network ports.
• Only enable remote access via VPN tunnel.
• Do not set up port forwarding at the communication port in use.
• In order to disable the Modbus interface, reset the inverter to the default settings or
disable the parameter again.
Procedure:
• Activate the Modbus interface and adjust the communication ports if necessary (see the
technical information "SMA and SunSpec Modbus® Interface" at www.SMA-Solar.com).
