What about the notice of the power supply of the surveillance camera?
A: The notice of the power supply of the surveillance camera: Do not share the same one power supply for the whole monitoring systems!

The reasons are as following:
1) When the system is repaired, it is often necessary to turn on and off the power supply. All surveillance cameras start at the same time when the power is turned on, the starting current is particularly large, and the impact on the power supply is very large, and the power supply will be burned in serious cases. 
2) All surveillance cameras share a power supply. When the power supply fails, the entire closed-circuit monitoring the system is paralyzed. In particular, the images of some important entrances and exits cannot be monitored, which may cause unnecessary trouble.

So that, what should be done for it? As the above example, a commercial building has 100 fixed surveillance cameras, which require a total of about 800W of power. The correct configuration should be to choose 4pcs of 200W each power supplies. In this way, when a certain power supply fails, the surveillance cameras at important entrances and exits can be connected to other good power supplies without affecting the work of the entire system.