TransCore MPRX, System Manual

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System Guide
TransCore Proprietary 4–12
Connecting Communications
The MPRX communicates through RS-232, RS-422, or Ethernet protocols.
Required Materials
You need the following materials to connect the communications cable to the host
device:
• Host device
• Any terminal emulation program such as Procomm Plus or Hyper Terminal operating
on a PC
• If the MPRX is connected directly to a TRU, all communications connections are
made through the MPRX-to-TRU cable assembly.
Connecting the MPRX to the Host
MPRX communications and customer interface signals are supplied from the MPRX to the
host through a multiwire cable. The connector for this cable is located on the end of the
MPRX (
Figure 4 – 6 ).
Plug one end of the MPRX communications/power interface connector into the M23
Host connector at the MPRX and the other end into the customer-supplied host device
connector. Refer to
Figure 4 – 7 and Table 4 – 2 for the pin assignments, numbers, and
wire colors.
Connecting Sense Input and Sense Output Circuits
The MPRX has two sense input circuits and a tag lock output circuit available. SENSE0
is used to enable RF on antenna ports 0 and 1 if enabled, and SENSE1 is used to enable
RF on antenna ports 2 and 3. The sense input circuits are used to notify the MPRX of train
presence and are designed to be connected to a free-of-voltage dry contact. The tag
lock output circuit is a single-pole, double-throw relay that provides a normally closed
and normally open dry contact. The relay contact is rated at 42.2V AC peak (30 Vrms) or
60V DC at 1 A maximum. If controlling an external gate or device requiring high current,
an isolation transformer is required.
Sense Input Circuits
The MPRX supports two sense inputs
–
SENSE0 and SENSE1
–
which require two
sense input lines (SENSEx and GND) for each loop sense or a total of four sense input
connections. SENSE0 is used to control RF power for the track that has antennas
connected to RF Ports 0 and 1. As shown in
Figure 4 – 7 , the sense inputs are wired through
the reader M23 Sense connector. The MPRX expects the SENSE0 circuit to close when a
railcar is present (on the track with antennas connected to MPRX ports 0 and 1).
SENSE1 must be closed when a railcar is present on the track connected to MPRX
antenna ports 2 and 3. The reader RF switches on to the appropriate RF ports
immediately upon detecting SENSEx.