As monitoring engineering practitioners must master the monitoring technical knowledge! The method of calculating the storage capacity required for monitoring projects and selecting special hard disk parameters is very important and basic! Speaking of storage, let's talk about hard drives first. What is the difference between the monitoring hard disk of the security industry and an ordinary hard disk? What's better than a regular hard drive? How to calculate the space required for storage.
In insecurity engineering, monitoring the hard disk required the hard disk is required to operate all year round. The disks that operate continuously all year round must be specially designed for the storage system. The monitoring hard disk as a perennial uninterrupted hard disk and ordinary hard disk differences are mainly reflected in the working time, starting current, power consumption and heat dissipation, and stability of four aspects.
Hours of service
Monitoring requires the continuous operation of hard disks. In this respect, ordinary hard disks are very different from monitoring hard disks.
A normal hard drive is designed to work continuously for 5X8 hours (8 hours a day, 5 days a week)
The monitoring hard disk is designed to work continuously for 7X24 hours (24 hours a day, 7 days a week), which can achieve an average trouble-free working time of 1,000,000 hours a year. Therefore, in terms of stability and reliability, monitoring hard disks undoubtedly win.
Start-up Current
Monitor hard disks ≤2.0 amps and optimize power configurations
Common hard disks ≥2.8 amps
Start the power supply is small, especially in the use of multi-disc video recorder, you do not have to worry about too much hard disk, start the current is too large, resulting in the problem of power burn out!
Power consumption and Heat dissipation
Monitoring hard disks ≤8W/ disk
Common hard disks ≥14.5W/ disk
Low power consumption not only puts less pressure on the power supply but also reduces the heat dissipation pressure. Monitor disk easier to keep “calm” work!
Stability
Monitoring hard disks: a professional seismic solution for multi-disk systems
Common hard disks: does not consider the earthquake resistance of multi-disk system
Hard disks are very shaky, but they vibrate slightly when they work. Monitoring hard disks can avoid the impact of vibration among multiple hard disks and prevent damage caused by vibration.
Now you understand the difference between monitor-level hard drives and ordinary hard drives.
Extra Episode: Resolution and bit rate
What do we calculate? In addition to the number of cameras and the amount of time you need to record, there is another important number: bitrate! In general, the larger the resolution, the larger the bitstream, for example, we commonly use a 130W camera, and the bitstream is 2MB/S, which is 2,048 KBPS. Then we know the code flow, time, and channel number, and we can directly apply the formula to calculate.:
Technical Term | Resolution(Pixel) | Bit Rate |
QCIF | 176*144 | 128Kb/s |
CIF | 325*288 | 512Kb/s |
DCIF | 528*384 | 0.7Mb/s |
HaflD1 | 702*288 | 1Mb/s |
D1(4CIF) | 704*576 | 1.5Mb/s |
FULL D1 | 720*576 | 2Mb/s |
720P | 1280*720 | 3Mb/s |
960P | 1280*960 | 3.5Mb/s |
1080P | 1920*1080 | 5Mb/s |
3MP | 2048*1536 | 7Mb/s |