Q-See QC40108 - Manual (Page 31)

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CHAPTER 8 HARD DISK DRIVE
PICTURE 8-1
PICTURE 8-2
STEP 2 . Remove the screw from the
hard drive cover. The cover will slide
upward for removal.
STEP 3 . Slide out the old drive (if
present). Insert the new drive into
the slot and slide into position. It
should fit snugly into the connectors
at the bottom.
DO NOT FORCE! If
the drive does not fit firmly, remove,
check alignment and reinstall.
Whether installing the drive for the first time or removing the old one to install a new one, the
steps are largely the same:
STEP 1 . Disconnect the DVR from the power source as well as any other connections.
STEP 4 . Replace the hard drive cover.
8.2 CALCULATING THE RECORDING CAPACITY OF A
HARD DISK DRIVE
While the physical data capacity of a hard drive is fixed, how much video you can record upon it depends
on your recording configurations. Higher quality recordings will take up more space on the drive and setting
the DVR to record for more frequently will fill it up more rapidly.
To determine the optimal capacity for your purposes, the chart below to estimate the size of hard drive that
you’ll need.
VIDEO
FORMAT
RESOLUTION FRAME
RATE
(FPS)
VIDEO
QUALITY
BIT
RATE
(kbps)
SPACE
USED
(MB/h)
NTSC CIF 30 Highest 1M 465
Higher 768k 297
Medium 512k 230
Low 384k 173
Lower 256k 115
Lowest 128k 56
D1 Highest 2M 910
Higher 1.5M 712
Medium 1M 468
Lower 768K 297
Lowest 512K 241
PAL CIF 25 Highest 1M 466
Higher 768k 295
Medium 512k 235
Low 384k 175
Lower 256k 112
Lowest 128k 56.4
D1 Highest 2M 915
Higher 1.5M 700
Medium 1M 465
Lower 768K 297
Lowest 512K 241
The formula for calculating the required disk space is:
Total Recording Capacity = Used space per hour (MB/h) x Recording time (hour) x
number of channels
Example: A customer is using the NTSC format (30 frames per second), CIF resolution
with video quality set to Lowest and a total of 16 Channels. He wants the unit to record
continuously for a month. Therefore, the calculation will look like this:
56(MB/h), x 24 (hours/day) x 30 (days) x 16 (channels) = 645,120MB or 650GB
Installing a 750GB SATA hard drive should provide enough space for one month’s continuous
recording time at those settings.