Installing the PRO3200 Two-Reader Module
Communications
PRO3200 Two-Reader Module Installation Guide, Document 800-15493
7
Note: POLARITY for 12VDC power is important. Make sure the +12 VDC is connected to the terminal
l12V and the return is connected to the terminal labeled GND.
Communications
The Two-Reader Module communicates to the host controller via an RS-485 interface.The interface
allows for multi-drop communication of up to 4,000 feet (1,200 m) total per port. Use two twisted pair
(minimum 24AWG) with shield for communication. The default speed of this port is 38.4Kbps but it
can be downgraded to 19.2Kbps or 9.6Kbps if the line conditions or receiving equipment require it
(see
on page 3 for jumper settings and
on page 4 for DIP switch settings).
For wiring to an RS-485 port:
1. TR+ is the plus side of the transmit and receive differential signal.
2. TR- is the negative side of the transmit and receive differential signal.
3. GND is the signal ground.The wiring for this signal is required and
NOT optional
. This signal
must NOT be connected to chassis GND.
4. Use 24 AWG low capacitance, two twisted-pair, shielded cable (Belden 9842 or equivalent).
Note:
For RS-485 Communication Connections, twist the blue pair together and use as the
common; use the orange pair as your data pair, observing polarity. Connect the external drain
shield to the appropriate earth ground on one end.
5. When daisy-chaining RS-485 ports together, connect the TR+ wires from the upstream and
downstream boards to the TR+ terminal. Likewise, connect the TR- wires from the upstream
and downstream boards to the TR- terminal.
By factory default J1 is set open. If this board is the last board on the RS-485 bus, install jumper J1
across both pins (closed). Closing J1 provides the bus termination required.
Wiring
This section presents information on reader wiring, input wiring, and control output wiring. The
following figure shows the PRO3200 board and identifies its terminal block pin assignments.