PICTURE
STEP 8. Place the HDD with the HDD cover back into the slot being careful not to pinch or bend the cables inside. Firmly tighten both thumbscrews.
PICTURE
STEP 9.
8.2CALCULATING 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 | RESOLUTION | FRAME | VIDEO | BIT | SPACE |
FORMAT |
| RATE | QUALITY | RATE | USED |
|
| (FPS) |
| (kbps) | (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.
CHAPTER 8 HARD DISK DRIVE
62 | 63 |