7
8
4.0 INSTALLATION
Once you have properly set the configuration switches and jumpers, you
are ready to connect the Model 2086 Series to your system. This section tells
you how to properly connect the Model 2086 Series to the RS-485 and RS-232
interfaces, and how to operate the Model 2086 Series.
4.1 CONNECTION TO THE RS-485 INTERFACE
To function properly, the Model 2086 Series
must have one or two twisted
pairs of metallic wire. These pairs must be”dry” (unconditioned) metallic wire,
between 19 and 26 AWG (the higher number gauges may limit distance).
For your convenience, the Model 2086 Series is available with either an
RJ-11 jack or RJ-45 jack.
4.1.1 4-WIRE CONNECTION USING RJ-11 OR RJ-45
The RJ-11 and RJ-45 connectors on the Model 2086 Series RS-485 side
are pre-wired for a standard TELCO wiring environment. The signal/pin rela-
tionships are shown below:
RJ-11
SIGNAL
RJ-45
SIGNAL
1...................GND*
1 .................N/C
2...................RCV-
2 .................GND*
3...................XMT+
3 .................RCV-
4...................XMT-
4 .................XMT+
5...................RCV+
5 .................XMT-
6...................GND*
6 .................RCV+
7 .................GND*
8 .................N/C
*Connection to ground is optional
In most modular RS-485 applications it is necessary to use a
"cross over" cable. The diagram below shows how a cross over cable
should be constructed for an environment where both the Model 2086
Series and the RS-485 device use a 6-wire RJ-11 connector. Similar
logic should be followed when using RJ-45 connectors or a combina-
tion of the two.
MODEL 2086 Series
RS-485 DEVICE
SIGNAL
PIN#
PIN#
RS-485 SIGNAL
GND
†
1 -------------------N/C
RCV-
2 -------------------4
XMT-B
XMT+
3 -------------------5
RCV-A
XMT-
4 -------------------2
RCV-B
RCV+
5 -------------------3
XMT-A
GND
†
6 -------------------N/C
4.1.2 2-WIRE CONNECTION
Most RS-485 devices employ a two-wire, half duplex configuration.
When using this configuration, be sure to first set the Model 2086
Series to "two wire" mode—then use
only the transmit (XMT) pair as
shown on the following page.
2086 Series SIGNAL
RS-485 SIGNAL
XMT+ ....................................XMT-A
XMT- .....................................XMT-B
The above wiring pattern applies regardless of whether you are
making the RS-485 connection via RJ-11 or RJ-45. For specific wiring
instructions, please refer to the previous page of Section 4.
4.2 WIRING FOR MULTIPOINT CIRCUITS
The Model 2086 Series supports multi-point applications using
either a star or daisy chain topology. Both topologies require special
wiring, as well as specific DIP switch settings for units.
Note: Refer to Section 3.0 for DIP switch settings.
1
2
3
4
5
6
7
8
1
2
3
4
5
6
Pair1
Pair 2
RJ-11
RJ-45
