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In the following system level technical description, the precise functions are explained to the in-
staller, as well as the user, which are required for the installation, operational start-up and handling 
of the solar inverter.
The content of renewable energy with respect to overall power consumption worldwide is increasing 
annually by approximately 25%. The reason for this rise can be primarily attributed to the constantly 
increasing demand for power, the increasing interest in environmentally friendly technologies, as 
well as the increasing costs of non-renewable energy.
By the use of renewable energy sources, the earth’s atmosphere can be enormously relieved of 
increases in CO2 and other harmful gases which result from power generation.
The solar inverter converts direct current from the solar cells into alternating current. This enables 
the inverter to feed self-produced solar energy into the public grid.
Thanks to ecient MPP tracking, maximum capacity utilization of the solar energy plant is ensured 
even in cases of misty and cloudy skies.
The string concept means that PV modules are always connected in series (in a string) and/or that 
strings with the same voltage are connected in parallel to the solar inverter with the aim of signi-
cantly reducing the photovoltaic system’s cabling requirements.
The fact that the modules are connected in strings also means that the photovoltaic system can be 
perfectly matched to the solar inverter’s input voltage range. 
The inverter is transformerless type without galvanic isolation. Therefore, the inverter may only be 
operated with ungrounded PV arrays. Furthermore, the PV arrays must be installed in accordance 
with the locally valid regulations for ungrounded PV arrays. Additionally, the PV array (PV modules 
and cabling) must have protective insulation and the PV modules used must be suitable for use with 
this inverter. PV modules with a high capacity to ground may only be used if their coupling capacity 
does not exceed 1,200 nF with 60Hz grid.
2.1 System
Delta Ex_BDI series were tested to the UL 1741 SB for CA Rule 21 and other Source Requirement 
Document (SRD) including “PG&E Electric Rule No.21 Hh” Jul,2017, “SCE Rule21 Hh”, “SDGE 
Rule21 Hh” and “HECO SRD V2.0”.
Contains NCC ID: CCAJ11LPxxxxTx
Delta Ex_BDI inverters qualify as PV Rapid Shutdown Equipment (PVRSE). It was evaluated with 
both SMART RSS and MCI device together.