44
AXIS 221 - The I/O Units Connectors
Schematic Diagram - Terminal Connectors
Example schematic diagram of the AXIS 221 Terminal Block Connector - showing possible
applications.
Pin
Function
Description
1
Output A
The external device output terminals (A and B) there is no distinction b
and -. The terminals use a photocoupler and are electrically isolated from the other
internal circuitry.
The maximum load should not exceed 100mA and the maximum voltage should be
no higher than 50V DC. Note: Connecting AC to the output will damage the unit.
2
Output B
3
Digital Input 1-
Photocoupler Anode (+)
Photocoupled Input 1: Electrically isolated from the chassis and connectors, this
input can be supplied from an external DC voltage or the DC Power Input/Output on
pins 9 (DC+) and 10 (GND).
4
Digital Input 1-
Photocoupler Cathode (-)
5
Digital Input 2-
Photocoupler Anode (+)
Photocoupled Input 2. As above.
6
Digital Input 2-
Photocoupler Cathode (-)
7
RS-485 - A (non-inverting)
A half-duplex RS-485 interface for controlling auxiliary equipment.
8
RS-485 - B (inverting)
9
DC + Power Output
DC Power Output: It can drive the photo coupler inputs or other equipment. The out-
put voltage level is 3.0 V. A maximum current of 100mA can be sourced from the DC
output.
10
GND
Ground.
o
o
Control
Device
o
o
o
o
A
B
3
4
5
6
7
8
External Device
Active
_
+
o
o
1
2
RS-485
Mains Power
24V DC
Appliance
Optional
Relay
Switch
o
o
o
o o
o
o
o
o
9
10
+
-
Switch, etc.
