Axis Communications 221 user manual Schematic Diagram Terminal Connectors

44AXIS 221 - The I/O Units Connectors

Pin	Function	Description
1	Output A	The external device output terminals (A and B) there is no distinction between +
2	Output 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.
3	Digital Input 1-	Photocoupled Input 1: Electrically isolated from the chassis and connectors, this
	Photocoupler Anode (+)	input can be supplied from an external DC voltage or the DC Power Input/Output on
4	Digital Input 1-	pins 9 (DC+) and 10 (GND).
	Photocoupler Cathode (-)
5	Digital Input 2-	Photocoupled Input 2. As above.
	Photocoupler Anode (+)
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.

Schematic Diagram - Terminal Connectors

o 1

o 2

o 3

	Optional
			o
		Relay		Appliance	o
	Switch		o
				o o
o o
24V DC				Mains Power
o o
Switch, etc.

				o						4
					o				5
						o		6
	A
RS-485			o									7
		o									8
	B												9
							+
							-10

+

Active

Control _ Device

External Device

Example schematic diagram of the AXIS 221 Terminal Block Connector - showing possible applications.