Axis Communications Axis 211A - Manual (Page 56)

56 AXIS 210A/211A - The I/O Terminal Connector
3. Once devices are connected, connect the terminal connector to the camera,
making sure that all cables are securely fastened.
Schematic Diagram - Terminal Connectors
Switch
Mode
Power
Supply
3.3V
PS-K 9W
e.g., doorbell
Relay
Device
GND
- +
+
2
1
3
4