SMA SB 3800-U - Manual (Page 40)

5-12 SMA America SB3800U-12:SE2006
Connecting Communication Cables
Various data-communication options are available for the SB3800U. These options are
provided in the form of accessory Piggy-Back modules that can be installed and
connected either at the time the inverter is installed or at any time thereafter. These
modules are not included with the SB3800U. Please contact SMA America for
information. Refer to the instructions included with the communication module for
installation procedures.
The following subsections provide instructions for connecting the various communication
cables between a SB3800U with a communication module and a personal computer
(PC). The connection of a SB3800U to a Sunny Boy Control or a Sunny Beam wireless
monitoring unit is shown in those respective manuals.
RS-232 Communication
RS-232 is a communication standard for bidirectional transmission of data between a
Sunny Boy and a PC. Only one Sunny Boy can be connected with an RS-232 serial cable
to a PC.
Requirements for RS-232 Communication:
• The SB3800U must be equipped with an RS-232 Piggy-Back communication mod-
ule.
• The cable should be no longer than 15 meters (50 ft.) Use the cable type specified
in the RS-232 Tech Note on www.sma-america.com.
• RS-232 cables are available from SMA America.
• Conduit may be required for communication wiring, per local electrical code re-
quirements.
Connecting an RS-232 Cable
Use the following procedure to install an RS-232 data-communication network:
1. Run the communication cable from the location of the PC to the SB3800U.
2. Verify that the PC has a serial port and that it is activated in the BIOS and the
operating system.
3. Attach the appropriate DB-9 connector to the end of the cable near the PC. See
Table 5-2 and Figure 5-7 for the pin assignments for the serial connector. Record
the wire color used for each of the pins listed in Table 5-2.
4. Route the other end of the cable into the SB3800U through the communication-
knockout on the bottom left of the SB3800U (see Figure 5-1).