There are four possibilities for the infrared light of the webcam and webcam not working:
There is a problem with the power supply of the equipment. The power of the webcam when the infrared light is turned on is larger than that when the infrared light is not turned on. Generally, the power is 2-3 times that when the infrared light is not turned on. If the power quality is not up to standard, or the wire diameter is not enough, or the total power supply UPS power is not enough, the infrared light will not be turned on.
The brightness of the environment where the camera is located is too high, and there are incandescent lights or other light sources around. The webcam will not enter the night mode, and the infrared light will not be turned on.
The infrared detector or camera is broken at all... Cover the infrared detector on the camera with your hand. If it is normal, the infrared light will be on.
Enter the camera settings menu, and some webcams can be forced to turn off the infrared mode, but they will not be turned on.