8 arc-fault circuit interrupter (afci), 9 sd card slot, 10 varistors – SMA SB 3000TL-US Installation User Manual
Page 24: 11 sma optitrac global peak

4 Product Description
SMA America, LLC
24
SB3-5TLUS22-IA-en-16
Installation Manual
4.8 Arc-Fault Circuit Interrupter (AFCI)
In accordance with the National Electrical Code
®
, Article 690.11, the inverter has a system for the
recognition of electric arc detection and interruption. An electric arc with a power of 300 W or
greater must be interrupted by the AFCI within the time specified by UL 1699B. A tripped AFCI can
only be reset manually. You can deactivate the automatic arc fault detection and interruption (AFCI)
via a communication product in "Installer" mode if you do not require this function. The 2011 edition
of the National Electrical Code
®
, Section 690.11 stipulates that newly installed PV systems attached
to a building must be fitted with a means of detecting and disconnecting serial electric arcs (AFCI) on
the PV side.
4.9 SD Card Slot
The inverter is equipped with an SD card slot. You can use the SD card when required to update the
inverter firmware.
4.10 Varistors
The DC Disconnect is equipped with four varistors on the DC side. Varistors are voltage-dependent
resistors that protect the inverter on the DC side against surge overvoltages. It may be necessary under
certain circumstances to replace the varistors (see Section 11.6 "Replacing DC Varistors", page 76).
Despite this protection against surge overvoltages, PV arrays must be designed in such a way that the
maximum system voltage of the inverter is not exceeded (see Section 13 "Technical Data", page 82).
4.11 SMA OptiTrac Global Peak
SMA OptiTrac Global Peak is a further development of the MPP tracking tool SMA OptiTrac. MPP
tracking is a process that determines the highest usable power in the PV system 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 optimum operating point for maximum power (MPP) changes
constantly throughout the day.
SMA OptiTrac ensures that the operating point of the inverter always follows the MPP exactly.
In addition, with the aid of SMA OptiTrac Global Peak the inverter can detect the presence of several
maximum power points within the available operating range, such as may occur with partially shaded
strings in particular. The available power of the partially shaded strings can therefore be almost
completely fed into the utility grid.
SMA OptiTrac Global Peak is deactivated as standard and should, in the event of partially shaded
PV modules, be activated and set via a communication product (see Section 8.7).