Axis 2120 User Manual page 57

AXIS 2120 User's Manual
The Physical Connector
A single 9-pin D-sub connector provides the physical connection for the RS232 serial interface of
the AXIS 2120. This connector is dedicated for use with an external modem and is suitable for
speeds up to 115kbps.
A diagram of the RS-232 connector complete with pinout information is shown below.
Pin Function
1 CD (Carrier Detect)
2 RXD (Receive Data)
3
TXD (Transmit Data)
4
DTR (Data Terminal Ready)
5
GND (Ground)
6
DSR (Data Signal Ready)
7
RTS (Return To Send)
8
CTS (Clear To Send)
9 RI (Ring Indicator)
The IO Connector
A 4-pole connector is provided for auxiliary IO connections to the AXIS 2120.
Physical Connector
The IO connector provides the interface to a single digital output and a single digital input. A
diagram for the connector, complete with a pinout table, is provided below:
Pin Function
1
Common Ground
2
Positive Connection for DC Power Input or Output:
Electrically in parallel with the derived DC power for the unit, this pin may be used as a
power input or output. As a power input it can be used for remote applications to supply
the AXIS 2120 via an external direct current source; for example, a 9-15V DC battery
supply. Used as a power output, it can drive the photo coupled input or other equipment;
such as an infrared sensor. The output voltage level is dependent upon the input voltage to
the unit. A maximum current of 50mA can be sourced from the DC output.
3 Digital Input (photo-coupled anode):
Voltages 5-24V DC will activate the input. It is possible to use pin 2 to source the input.
4
Digital Transistor Output:
With a maximum load of 100mA and maximum voltage of 24V DC, this output has an
open-collector NPN transistor with the emitter connected to pin 1. If it is to be used with
an external relay, a diode must be connected in parallel with the load for protection
against any voltage transients - as detailed in the Schematic Diagram, on page 59.
Important! Connecting AC to the transistor output will damage the unit.
Appendix C - The Unit Connectors
A view of the RS-232 connector as seen from
the rear of the AXIS 2120
1 2 3
6
7
4 5
9
8
4
3
2
1
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