DVR User Manual
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Appendix 3.Hard disk capability calculation
Make sure the hard disk is installed to the DVR 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 120G~ 250G sizes 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 DVR 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 500G HDD, real time CIF for recording, it will keep recording for about 25 days.
HDD spaces per channel is 200M/H, if 4 channels real time CIF at 24hours recording uninterrupted,
it can last: 500G/ (200M/H*24H*4ch) =26 days.
