Publication 1762-UM001D-EN-P - March 2004
4-12 Communication Connections
Grounding and Terminating the DH-485 Network
Only one connector at the end of the link must have Terminals 1 and
2 jumpered together. This provides an earth ground connection for
the shield of the communication cable.
Both ends of the network must have Terminals 5 and 6 jumpered
together, as shown below. This connects the termination impedance
(of 120 ohm) that is built into each AIC+ as required by the DH-485
specification.
End-of-Line Termination
Connecting the AIC+
The AIC+, catalog number 1761-NET-AIC, enables a MicroLogix 1200
to connect to a DH-485 network. The AIC+ has two RS-232 ports and
one isolated RS-485 port. Typically, there is one AIC+ for each
MicroLogix 1200. When two MicroLogix controllers are closely
positioned, you can connect a controller to each of the RS-232 ports
on the AIC+.
The AIC+ can also be used as an RS-232 isolator, providing an
isolation barrier between the MicroLogix 1200 communications port
and any equipment connected to it (i.e. personal computer, modem,
etc.).
Jumper
Jumper
Belden #3106A or #9842 Cable
1219 m (4000ft) Maximum
Jumper