User's Manual

905U-K Radio Telemetry Module User Manual
 ELPRO Technologies Pty Ltd 2001 Page 26
3.5.2 Shaft Encoder Connections
⊂
⊂
⊂
COUNT
DIRECTION
GND
DIN2
DIN1
905U-K
⊂
⊂
⊂
PHASE 1
PHASE 2
GND
DIN2
DIN1
905U-K
INCREMENTAL SHAFT ENCODER
QUADRATURE SHAFT ENCODER
Analogue input The analogue input has a positive and a negative terminal, and may be placed
at any point in the current loop, as long as neither input rises more than 24V above COMMON
or ground. A 24 VDC 30mA supply is provided for powering analogue loops. The analogue
loop may be powered from the internal supply or may be externally powered.
⊂
⊂
GND
AI-
905U-K
⊂
⊂
+
-
AI+
905U-K
⊂
LOOP POWERED TRANSDUCER
EXT POWERED TRANSDUCER
⊂
⊂
⊂
+
-
AI+
AI-
ANALOG
SUPPLY
Shielded cable is recommended for analogue 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. Each input has a loop resistance of 150Ω and zener diode protection against
overvoltage and reverse voltage. Additional surge protection is recommended in high
electrical noise environments, or if the analogue signal cable runs for a long distance
underground before connecting to the 905U-K module.
3.5.3 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.
Communication is via standard RS-232 signals. The 905U-K is configured as DCE equipment with
the pinout detailed below.