505U-K Radio Telemetry Module
Page 30
© April 2002
electrical noise environments, or if the analogue signal cable runs for a long distance
underground before connecting to the 505K module.
Voltage Input
Voltage inputs are connected to the AI+ and
AI- connections. The maximum voltage signal
that can be measured is 10V.
The analogue signal is set up for a 4-20mA
signal in the factory. To use a voltage input,
change the jumpers inside the module:
1.
Remove the lid from the unit.
2.
With the unit oriented with the antenna connector at the top of
the unit, locate a set of selector jumpers at the bottom right
corner of the box.
3.
Using long-nose pliers, remove the two jumpers bridging the
left-hand and middle pins, and insert the jumpers between the
middle and right-hand pins. When the jumpers are on the left
side, the analogue input is set for a mA signal; when on the
right side, it is set for a voltage signal.
Shielded cable is recommended for both mA and voltage analog
input loops to minimise induced noise and radio frequency
interference (RFI). The shield of the cable must be connected to
earth at one end of the cable only. Additional surge protection is
recommended in high electrical noise environments, or if the
analog signal cable runs for a long distance underground before
connecting to the 905K module.
3.5.4
RS232 serial port
An RS232 port is provided for connection of a PC for configuration and diagnostics. To
access the serial port DB9 connector, remove the front cover from the module by unscrewing
the four screws in the front panel. The serial port is a 9 pin DB9 male and provides for
connection to a terminal or to a PC for configuration, field testing and for factory testing.
mA V
⊂
+
-
AI+
505U-K
⊂
VOLTAGE INPUT
AI-
⊂
⊂
GND