4 Product Description
SMA Solar Technology AG
24
STP5-9TL-IA-en-10
Installation Manual
4.7 Slot for the Power Control Board
The inverter has a slot for the Power Control Board. The Power Control Board can be retrofitted or
installed at the factory, if a respective order is placed.
The Power Control Board enables the inverter to perform grid management functions (you will find
installation and configuration instructions in the installation manual of the Power Control Board).
4.8 Grid Management
The inverter is equipped with grid management functions.
Depending on the requirements of the network operator, you can activate and configure the functions
(e.g. provision of reactive power, active power limitation) via operating parameters (for information
on the functions and operating parameters, see the Technical Description "Measured Values and
Parameters" at www.SMA-Solar.com).
4.9 SMA OptiTrac Global Peak
SMA OptiTrac Global Peak is a more advanced form of the SMA OptiTrac MPP tracking.
MPP tracking is a feature that determines the highest usable power in the PV plant at any given time.
The power generated by the PV array depends on the level of solar irradiation and the temperature
of the PV modules. As a result, the optimal operating point for the maximum power (MPP) changes
constantly throughout the day.
SMA OptiTrac ensures that the operating point of the inverter always coincides exactly with the MPP.
Moreover, the inverter detects the presence of several maximum power points in the available
operating range via SMA OptiTrac Global Peak, as they can occur with partially shaded PV strings.
Thus, the full power of the partially shaded PV strings can be almost completely fed into the electricity
grid.
SMA OptiTrac Global Peak is deactivated by default. With partially shaded PV modules, it should be
activated and set via a communication product (see Section 9.6).
4.10 Varistors
Varistors are voltage-dependent resistors that protect the inverter against overvoltage. The inverter is
equipped with thermally monitored varistors.
Varistors can become worn and lose their protective function with age or repeated strain as a result
of overvoltage. The inverter detects if one of the varistors is defective and indicates an error.
The varistors are specially manufactured for use in the inverter and are not commercially available.
You must order new varistors directly from SMA Solar Technology AG.