Rockwell Automation 1440-VLF02-01RA XM-121 Absolute Shaft Module - Manual (Page 42)

Publication GMSI10-UM014D-EN-P - May 2010
34 Installing the Absolute Shaft Module
Figure 2.22 4-20 mA Output Connections
Serial Port Connection
The XM-121 includes a serial port connection that allows you to connect a PC
to it and configure the module’s parameters. There are two methods of
connecting an external device to the module’s serial port.
• Terminal Base Unit - There are three terminals on the terminal base
unit you can use for the serial port connection. They are TxD, RxD, and
RTN (terminals 7, 8, and 9, respectively). If these three terminals are
wired to a DB-9 female connector, then a standard RS-232 serial cable
with 9-pin (DB-9) connectors can be used to connect the module to a
PC (no null modem is required).
The DB-9 connector should be wired to the terminal block as shown.
ATTENTION
The 4-20 mA outputs are functionally isolated from other
circuits. It is recommended that the outputs be grounded at
a single point. Connect the 4-20 mA (-) to the XM terminal
base (Chassis terminal) or directly to the DIN rail, or
ground the signal at the other equipment in the 4-20 mA
loop.
XM-121 Terminal Base Unit
(Cat. No. 1440-TB-A) DB-9 Female Connector
TX Terminal (terminal 7) ---------------------- Pin 2 (RD - receive data)
RX Terminal (terminal 8) ---------------------- Pin 3 (TD - transmit data)
RTN Terminal (terminal 9) --------------------- Pin 5 (SG - signal ground)
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