Dahua HD IR Vari-focal Dome Network Camera Quick Start Guide
6
Connect network cable to corresponding network port of the device cable according to
“Install
Waterproof Connector (Optional)
”.
Connect Alarm Input/output Port
Note
Some models do not support alarm function, which cannot be applied to this chapter.
Step 1
Connect alarm input device to the alarm input of I/O port.
When the input signal is idle or grounded, the device can collect the different statuses of the alarm
input port. When the input signal is connected to 3.3V or it is
idle, the device collects the logic “1”.
When the input signal is grounded, the device collects the logic “0”.
Figure 2-3
Step 2
Connect alarm output device to the alarm output of I/O cable, alarm output is collector open circuit
output which connects pull-up10K resistor to 3.3V externally.
Mode A
: Level application. Alarm output high and low level, alarm output is OC; it needs to increase
pull-up resistance externally to work normally. Max external pull-up level is 5V, max port current is
5mA. After external pull-up resistance is increased, the default of output signal is high level (external
pull-up voltage), and it switches to low level when there is alarm output (when the working current is
5mA, output voltage is less than 0.8V).
Mode B
: Switch application. Alarm output is used to drive external circuit, max current is 30mA, max
voltage is 5V, it is advised to add a relay if it is beyond the value.
