User manual

Page
64
Appendix 3.Hard disk capability calculation
Make sure the hard disk installed to the NVR for the first time. Pay attention to the IDE hard disk
lines connection.
1、 Hard disk capability
There is no limit for recording machine. We recommend 500G~1000G size to keep better
stability.
2、 Overall capability option
The hard disk capability formula is:
Overall capability（M）=channel number*time（hour）*capability in an hour（M/hour）
The recording time formula is:
Recording time（hour）=
overall capability（M）
Capability in an hour（M/hour）*channel number
The NVR introduces the H.264 compression technology. Its dynamic range is very large so the
hard disk capability calculation is based on the estimation values of each channel creating files in
an hour.
Example:
For one piece 1000G HDD,4 cameras record at 3Mbps,it will keep recording for about 7.7 days.HDD
spaces per channel is 1350M/H,if 4channels with 3Mbps at 24hours recording uninterrupted,it can
last:1000G/(1350M/H*24H*4ch)=7.7 days
Bit Rate Conversion：
1 Byte= 8 bit ,1MB = 1024KB ,1Hour = 3600secs
1 Kbps = 1/8 KBps = 1/8/1024 MBps = （1/8/1024）*3600 MB/H
1 Mbps = 1/8 MBps = (1/8) * 3600 MB/H = 450M/H