The importance of proper selection of monitoring power

Surveillance cameras need power to work, otherwise they go on strike. The commonly used methods are nothing more than PoE power supply, centralized power supply and independent power supply. Here are some questions to discuss the importance of power supply.

1. The surveillance camera indicates the DC12V/AC24V universal. What kind of power source should be selected?

A: Select AC 24V monitoring power supply, because the same transmission distance, the higher the voltage, the smaller the loss. When the voltage is high, the load can get a sufficient voltage.

2. How to properly configure the monitoring camera power supply power of the entire monitoring system?

A: This problem often makes young, inexperienced engineers have difficulties. Many programs find that the original power supply capacity was inadequate and they needed to add additional equipment. In fact, because the camera starts at a momentary instant and the starting current is very large, coupled with the loss of long-distance transmission over the project, the power required by the surveillance camera is not simply the sum of the rated power of all cameras.

The correct approach is to add the rated power of the camera of the entire surveillance system by a factor of 1.3. This is the actual power required by the surveillance camera, plus about 30% of the loss, and finally a 30% margin. As a future expansion.

If a business building has 100 fixed gun cameras and each surveillance camera has a rated power of 4W, how do we configure the camera's power supply?

According to the above calculation method, we calculated that the rated power of the surveillance camera is 4W*100 units=400W

The actual power used by the camera is 400W*1.3=520W

After considering the loss, the power required by the surveillance camera is 520W*1.3=676W

In addition to the power supply margin, the power required to configure the surveillance camera is 676W*1.3=878W.

Summarized as follows: Monitoring camera needs to configure the power power = rated power of the camera *1.3*1.3*1.3

(Note: If the monitoring distance is extremely long, it is necessary to increase the power supply and increase the power supply voltage.)

3, surveillance camera power configuration, the most taboo what?

A: The most taboo is: The entire monitoring system shares a power supply. The reason is as follows:

1) When the system is being repaired, it is often necessary to turn the power on and off. All surveillance cameras are started at the same time when the power is turned on. The start-up current is particularly large. The impact on the power supply is great, and the power will be severely burned.

2) All surveillance cameras share a single power supply. When the power supply fails, the entire CCTV system is paralysed.

What should be the correct approach? As the above example, a commercial building has 100 fixed surveillance cameras, which require a total of about 800 W of power. If PoE is required, the correct configuration should be to select 4 sets of 200 W PoE switches. This requires a 16-port PoE switch. Series and 24-port series PoE switches are satisfied. In this way, when a certain switch fails, the cameras at the important entrances and exits can be connected to other good switches so as not to affect the work of the entire system.

4, monitoring camera power supply selection also need to pay attention to what the problem?

A: First, when connecting the camera to the power supply, do not connect the camera with a long distance away and the surveillance camera with a short distance to the same power supply. If connected to the same power supply, if the power supply voltage is high, the camera at a short distance will be burned, the power supply voltage will be low, and the camera at a relatively long distance will have no image. You should try to connect the surveillance cameras that are far away from one another to the same power supply and connect the closer cameras to the same power supply.

Second: If the monitoring distance is too far, you need to configure a higher voltage power supply, such as 30V, 36V, etc., or even directly for 220V AC power, to the front and then change the pressure.

5, in the specific construction process must pay attention to the power connection. Especially when powering 220V.

If the system uses 220V power supply, when the power supply is changed, the power of this group of monitoring power lines must be completely disconnected to be replaced. How to use a plug in the early stages of construction is much more convenient, or it is now popular.

Fengrunda provides a variety of monitor-specific PoE switches, with dozens of different types. Welcome to do monitoring and consulting.