American Fibertek RR-944C - Manual (Page 5)

5
TYPICAL SYSTEM DATA CONNECTIONS
The RS422 or RS485 four wire interconnection between the RR-944 and the copper device to which it
is attached is based on industry standard EIA terminology for the transmission of electronic data
signals. Using this terminology, the driver of an electronic signal is labeled TX or Data Out.
Correspondingly, the receiver of an electronic signal is labeled RX or Data In. Following this standard,
the TX or Data Out of the copper device is connected to the RX or Data In of the RR-944. The plus
terminal of the copper device is connected to the plus terminal of the RR-944 and the minus is
connected to the minus. The reverse flow of data from the RR-944 to the copper device follows the
same pattern. Not all manufactures follow standard EIA terminology. Consult the installation
instructions for your copper device if you are unsure which two wires are the drive (data out) wires and
which two wires are the receive (data in) wires.
Please note that Data In on the RR-944C becomes Data Out on the MT-944C or the RT-944C after
going across the fiber. The reverse flow follows the same orientation.
DATA CONFIGURATION SWITCHES
NOTE: This unit is shipped with the Data Channel in the RS485 4-wire configuration.
For other configurations of data channel, please refer to the drawing below for changes to the default
switch settings. These configuration switches are located on the top of the unit and can be switched
without opening the unit.