QTech Data Systems DNP3 RTU - Manual (Page 10)

DATRAN XL4 RTU – Owners Manual – v1.1 June 2012
www.qtech.co.nz Page 10
The connector used for the RS485 port looks similar to the one used on
the Q03. Care must be taken! The connectors are NOT the same.
Forcing a plug intended for a Q03 into a Q04 can damage the socket.
Connections Connections Connections Connections
The following connection ports available on the XL4:
RS485 Port RS485 Port RS485 Port RS485 Port
The RS485 port is used for inter-module long distance, high speed communications. The RS485 port features
2,500Volt galvanic isolation and both 2 and 4 wire operation.
The RS485 port has inbuilt provision for line termination. In RS485 applications, especially over long lines, the
RS485 transceivers at either end of the line should be terminated with a 120 ohm load. In multi-drop RS485
applications only the far end RS485 transceivers should be terminated. The RS485 serial can operate in a multi-
drop configuration allowing a maximum of 32 devices to be connected to the RS485 line.
The RS485 port can be extended up to a maximum distance of approximately 1000 meters with appropriate cable
and installation. It is generally recommended to install a 3
rd
party surge protection devices on any exposed RS485
cable runs, or runs exceeding 200 meters in length.
Function
Pin 1 Not Used
Pin 2 Not Used (Yellow)
Pin 3 485 + (Green)
Pin 4 485 – (Red)
Pin 5 Ground (Black)
Pin 6 Not Used
Note. RJ12 cable connector pin numbering
RS485 – RJ12 Connections
RS232 Ports
The XL4 RTU contains two RS232 serial ports used for specialised communication devices and peripherals.
These include PLC Interfaces, Cellular modems, Data Radios, modems etc. The specific application and required
settings are configured using the QTech Workbench configuration software. The RS232 serial port connectors are
both 8 way RJ45 connectors. One is located on the Q04 processor board, labelled RS232-A, while the other is
located on the Q22 I/O board, labelled RS232-B.
The RS232-B port can be configured via J23 on the Q22 I/O board to provide an output voltage (+V
sup
) on pin 8.
This is of specific use for the Q71 external 1200bps modem. Please refer to the Q71 Quick Start Guide for further
details.
Standard 8 way RJ45 crimp plugs are used in making up serial port interconnection cables. These plugs are
designed for use with stranded (24/26 AWG) 8 core flat data cable. An RJ45 crimping tool must be used to crimp
the RJ45 plugs onto the data cable to ensure proper and reliable crimping. Improperly crimped connectors can
damage the RJ45 socket and cause unreliability.