SMA Sunny Data Control V.4.2 - Manual (Page 141)

SMA Technologie AG Transferring Data to the Internet
User Manual SDC-TEN080642 Page 141
The tool "SDC agent" serves as a communication intermediary between the Java
applets and Sunny Data Control. For this purpose, it is installed on the HTML web
server's computer. The communication between the applets and the agent, as well as
between Sunny Data Control and the agent, occurs via a dedicated TCP connection.
Two different modes of connection from the PV plant to Sunny Data Control serve as
the information source for the applets' display of measured values.
Direct Connection
The Sunny Boy Control is permanently in contact with Sunny Data Control via a direct
RS232 / RS485 connection. The measured values are queried directly from the
connected PV plant, and transferred to the Internet.
This mode enables the entire range of all different display types to be shown on the
applets. This mode is preferable, as it offers the most possibilities.
Offline Connection
With this mode, there is no permanent connection between the Sunny Boy Control and
Sunny Data Control (e.g. only a temporary modem connection). The only data source
is the content of the online data file (see section 12.5. 1 „Writing the Online Data File”
(page 134)).
This only enables the applets to show the device field display. No other display types
are possible.