QTech Data Systems DNP3 RTU - Manual (Page 3)

DATRAN XL4 DNP3 RTU – Quick Start Guide – v1 – May 2012
www.qtech.co.nz Tel: +64 3 3663713
The connector used for the XL4 RS485 port looks similar to the one used
on the Q03. Care must be taken as forcing a Q03 RJ10 plug into a Q04
can damage the socket.
If the RTU is to be supplied from 24V it is necessary to
change J27, located on the Q22 (bottom board) in the
RTU. This changes the low voltage shutdown voltage to
21V.
Power Supply Connections
The XL4 power connector has three connections:
-V = Power Supply Negative
+V = Power Supply Positive, 12 – 30 V DC
O/P = Control Signal Output. This allows the RTU to turn on devices when it
is powered up. This was previously labelled “C” on eXcel RTUs
The “O/P” terminal is an OUTPUT. Do not connect it to the supply.
The XL4 and associated peripherals should all share a common earth point.
RS485 Port
The XL4 RS485 port is an RJ12 connector, identified by having 6 contacts,
as shown. The previous Q03 RS485 connectors were an RJ10 connector
with 4 contacts. Ensure that the 6 contact RJ12 is plugged into the XL4
RTU. Do not attempt to insert the 4 contact RJ10 into the RTU, this must be
inserted in the expansion module (Q23/Q26 etc).
Digital Inputs
The RTU digital inputs are designed to interface easily with physical switching devices.
They have an internal pull-up resistor that will pull the input
terminal to the power supply ‘+’ when the input is open circuit
(the “OFF” state).
To turn a digital input ON, connect it (via a set of contacts if
necessary) to the common “G” terminal on the Digital Input
terminal block. All “G” terminals on the XL4 RTU are tied
internally to the “V-” terminal on the power supply connector.
The LED associated with each digital input will light up when the input is Active/On/Closed.
The pull up / pull down convention is different from some PLCs. If required, the
active state of I/O can be inverted in the XL4 RTU DLP control program or PLC
Low Voltage Drop Out
Threshold
J27
12V supply Installed
24V supply Open