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000481AG
7 - Operation
M
odbus TCP Gateway Functionality
The
Modbus TCP Gateway
functionality allows an external monitoring
or a
SCADA
system to exchange data with the inverter without being
directly connected.
Communication with the
SCADA
or external monitoring system must
take place through the Modbus TCP protocol. The VSN300 board server
/ gateway converts the Modbus commands which arrive and sends them
to the inverter (or to any device within which the board is installed). In
turn, the responses generated by the inverter will be converted and sent
to the Modbus client which has sent the commands.
R
ole of the Sunspec Adapter software
Integration of the VSN300 in a
SCADA
system is made possible mainly
thanks to the
Modbus TCP
communication protocol and the presence of
the
SunSpec Adapter
software.
The
SunSpec Adapter
is a software adapter that has two main functions:
it continuously polls
legacy ABB
inverters as fast as it can using the
Au-
rora Protocol
and caches data polled from these inverters in SunSpec
compliant Modbus data maps.