4 Product Description SMA Solar Technology AG
18 SB13_21TL-IA-en-65 Installation Manual
4.7 Operating Parameters
The performance of the inverter is controlled by various operating parameters. The operating
parameters of the inverter can only be adjusted using an SMA communication product
(for information on the operating parameters, please refer to the Technical Description
"Operating Parameters" at www.SMA-Solar.com).
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. active power limitation) via
operating parameters (for information on the functions and operating parameters, see
Technical Description "Operating Parameters" at www.SMA-Solar.com).
4.9 Varistors
Varistors are voltage-dependent resistors to protect the inverter against overvoltage. The inverter is
equipped with thermally monitored varistors.
Varistors are subject to wear with age or repeated strain as a result of overvoltage, which diminishes
their protective function. The inverter detects if one of the varistors is defective and signals an error
(see Section10.5.2 "Checking the Function of the Varistors", page55).
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.
4.10 SMA Grid Guard
SMA Grid Guard acts as an automatic disconnection device between a grid-parallel generator
(e.g. a PV plant or small wind turbine system) and the electricity grid.
Furthermore, SMA Grid Guard is a grid monitoring concept, which detects errors by permanently
monitoring grid impedance, mains voltage and mains frequency. For example, SMA Grid Guard
detects when a stand-alone grid is formed and disconnects the inverter from the electricity grid
immediately.
In some countries, the connection conditions stipulate installation of a device which protects
grid-relevant operating parameters from unauthorised changes. SMA Grid Guard performs this
function.
Some country data sets are automatically protected after the first ten feed-in hours. After the initial ten
feed-in hours, the protected country data sets can only be changed via a communication product and
by entering a personal access code, the SMA Grid Guard code (for information on how to change
parameters, see communication product manual). You can obtain the SMA Grid Guard code from
SMA Solar Technology AG (to apply for the SMA Grid Guard code, see certificate "Application for
the SMA Grid Guard Code" at www.SMA-Solar.com).
