Use the General I/O Interface (GPIO) on the front end of main unit to access an external wired alarm devices like PIR sensor, Gas Detector, Infra-red pool alarm and etc.

The terminal definitions are described below :

POWER: This terminal can provide DC power to a wired alarm devices. The max power for external device is 12VDC ± 5%, 0.5A.

This  is a optional, you can  use the alarm device with an external power supply.
WARNING: The maximum rating voltage of alarm device CAN NOT less than 12VDC, or you will damage the alarm device.

DO: With a maximum load of 400mA and a maximum  voltage of 40V DC, This terminal has an open-collector NPN Darlington transistor with the emitter connected to the GND  terminal.

If used with an external relay, a diode must be connected parallel with the load, for protecting against voltage transients.

Please refer to the following diagram for the connection method.

Be careful about choosing  Open or Grounded when connecting to an alarm or other device, you need to make the relevant settings to the camera as the picture below:
(Login web application –> Task –> Digital I/O Setup )

The Grounded  means that  DO short  to GND  inside the camera.
The  Open  means  that  DO is floating  inside the camera.

DI: This terminal which is used to connect the relay output of wired alarm device like PIR sensor, Gas Detector, Infra-red pool alarm and etc.

Be careful about choosing  Open or Grounded  when connecting to the terminal  of  alarm output, you need to make the relevant settings to the camera, do it like this: setting–> Task–> Digital I/O Setup–> you can do it as the picture below:

The  Grounded means that DI is shorted to GND. In this way, DI should be connected to N.O(Normal Open) terminal.
The  Open means that DI is floating from GND. In this way, DI should be connected to N.C (Normal Close) terminal.

GND: This terminal used to COM terminal for Relay output of alarm device. When Terminal 1 connect +DC terminal of alarm device, please connect  this terminal to GND or –DC terminal of the device.
This is an optional, you can use the alarm device with an external power supply.