How to choose security monitoring and power supply plan

Power supply for security monitoring equipment is the most concerned issue for security engineers. In recent years, almost all security monitoring manufacturers are pushing PoE cable power supply, but why is the security monitoring equipment powered by strong power and centralized power supply? Let us first understand the three modes of security monitoring and power supply.

The security monitoring power supply mode mainly includes: point-to-point independent power supply (commonly known as deploying strong power, using power adapter to supply power), centralized power supply, and PoE network power supply.

First, point-to-point independent power supply mode

Point-to-point independent power supply means to directly draw 220V AC from the monitoring room, use the wire/combination line (network cable + wire) in the middle, then connect a separate DC12/24V power adapter to the camera, and then connect it to the surveillance camera. Each power supply only Provide power to a camera.

1. Advantages of independent power supply

Easy to repair and replace: When the camera malfunctions, it can quickly detect the fault and repair or replace the equipment;

The power supply distance is far: the use of strong 220V output, can be cascaded, the power supply distance is long, and basically no loss.

2. Insufficient independent power supply

The cost is relatively high: the cost of deploying multiple independent monitoring power adapters is higher than that of a centralized power supply with the same power output;

The safety and stability are weak: the strong electricity is weaker than the weak electricity, and the line aging + rat damage is easy to cause short circuit or even fire. Moreover, the independent monitoring power supply and the camera are mostly in an outdoor environment, and are susceptible to external force damage factors such as lightning strikes.

Second, centralized power supply mode

Centralized power supply means that 12/24V 4A centralized power supply is connected to the 220V power supply, and then connected to the camera by 2*1.0 red and black power supply/combination lines, without installing a power adapter on the front end of the camera. The biggest difference in this mode compared to the point-to-point independent power supply mode is that one power supply can provide power to multiple cameras.

1, the advantages of centralized power supply

Lower cost: Thanks to the high cost performance of centralized power supply, the power supply system with centralized power supply mode has lower cost;

Simple maintenance: adopt centralized power supply mode, convenient route laying, convenient construction and easy management.

2, the disadvantages of centralized power supply

Complex deployment in the early stage: The power of centralized power supply is not simply the sum of the power of all surveillance cameras, but also the loss of power. The wire rods on the market are uneven, so this method requires high engineers.

There is a system risk: If the UPS power supply is not used, if there is a problem in the power supply system in the centralized power supply mode, the entire monitoring system will not work properly and will be in a paralyzed state.

Third, PoE network cable power supply mode

PoE network cable power supply refers to the mode that can supply power to the front-end network camera and transmit data through a network cable without any modification in the existing Ethernet cabling structure. There are two main types of power supply methods for mainstream PoE cables on the market.

1, 12/24V passive PoE network cable power supply (commonly known as non-standard PoE power supply)

advantage:

The lowest cost: generally use the 45+78-line power supply of the network cable. With the corresponding rotating voltage separator, many front-end devices that do not support the power supply of the network cable can solve the problem of power supply and data transmission only through one network cable.

Disadvantages:

The deployment is more complicated: you need to know the voltage of the powered device, choose the corresponding switch and splitter. It is not recommended to choose the 12V passive power supply switch and the straight-through type splitter, because the transmission distance of the 12V passive power supply switch is basically only when transmitting the same power. At 30 meters, there will be insufficient voltage and serious power loss. 24V can be used for power supply below 15W, and the distance can reach 100 meters.

Poor security and stability: Most of the existing 24V/12V network cable power supply switches on the market are direct-supply, and the power supply is basically a poor quality power supply without 3C certification. The switch ports also have no lightning protection, which brings potential safety hazards to the subsequent use of the products.

In response to the above problems, a highly reliable 24 volt PoE power supply switch is introduced. The full range of products adopts 3C certified power supply with 6KV protection. All ports of the switch support 6KV lightning protection and three-speed dial power switch control. With 24V to 12V splitter, it can solve the problem of complicated deployment of non-PoE camera, access control, bridge and other front-end equipment during project deployment.

2, 44-57V standard PoE network cable power supply

advantage:

Strong security compatibility: Contains PSE chip, which detects the access to the standard equipment before it is powered. Non-standard PD devices such as PCs, switches, and NVRs can also be connected casually without burning the device; they conform to the af/at standard and are plug and play.

Disadvantages:

The cost is relatively high: the front-end equipment needs to add the PD chip, and the switch needs to add the PSE chip, so the overall product price is relatively high.

Fourth, the choice of security monitoring power supply mode

How to choose the power supply mode depends on the customer's installation environment and actual needs. The recommendations are as follows:

1. If the on-site strong power deployment is already good, the power is convenient and the cost is low. Then choose the point-to-point power adapter or centralized power + common switch to solve the data transmission and power supply problems of the front-end equipment.

2. If the front-end device does not support the terminal equipment powered by the network cable, the deployment of strong power is troublesome and the cost is high. Then choose the corresponding buck separator +24V non-standard network cable power supply switch is to solve the data transmission and power supply problem of the front-end equipment cost-effective choice.

3. If the front-end device is a terminal device that supports the power supply of the network cable, the deployment of strong power is troublesome and the cost is high. Then choose the corresponding 44-57V standard PoE network cable power supply is to solve the problem of cost-effective choice for front-end equipment data transmission and power supply.

V. PoE network cable power supply prospects can be expected

More and more PoE equipments displayed by large and medium-sized enterprises in the security exhibitions in the past two years can be seen that PoE network cable power supply technology is gaining momentum. However, because the cameras produced by several major security giants in China do not support the PoE power supply and PoE power supply, the PoE power supply switch has higher cost and uneven equipment quality. Some manufacturers have poor lightning protection performance, large power consumption and heat dissipation. Poor and other reasons, the engineering business friends think that PoE equipment is not reliable, prefer to use independent power supply or centralized power supply to solve the power supply problem of surveillance cameras, making PoE power supply has not become mainstream.

It is believed that with the gradual decline in the price of products supporting the front-end PoE power supply equipment, more and more manufacturers are launching cost-effective PoE network cable power supply switches, and the labor costs of engineering projects are gradually increasing. Engineers are beginning to realize the application of PoE splitters and PoE power supply switches. Value, PoE power supply technology will eventually become the mainstream of security monitoring power supply.