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Hints and tips for the industry

ESDA has invited its members to supply hints and tips to the industry. This opportunity is open to all members of ESDA and is aimed to increase the level of professionalism in the security industry. The first submission is from Niall Beazley from Vision Catcher:

Installer lessons the hard way - digital installations

1. Frame speeds: Digital recorders using PCI cards have a number of BNC camera inputs - these cards allocate frame rates across the card, dependent upon number of processors, each processor normally supporting 25 frames per second. In the case of a 4-card input and one processor, the frame rate will be divided by the number of cameras used - allowance must be made for nonsynchronisation and this results in a theoretical frame rate in this example of 25/4 = 6,25 fps, but in reality gives nearer to 2,5 fps per input or 10 fps across the card. In a 16 camera DVR you will see four cards, averaged at 2,5 fps per input giving a total of 40 fps.

2. Prioritise on cameras: When connecting BNC's to a DVR with 16 channels it is important to put your four main cameras onto inputs 1,5,9 and 13. Your next set of four cameras onto 2,5,10 and 14 etc. The reason for this is to be able to prioritise on camera views, so that when you open a quad screen you will see your most important cameras. Likewise, in remote viewing you can de-activate through remote control the other cameras and increase the frame speed to a full 25 fps per camera.

3. Some camera pictures bounce up and down slightly: This is caused by power near the video cable or a loss of impedance owing to poor cabling, kinks in cable, poor BNC connections, wrong cable, or reduced power at camera point. Solutions are to check cable runs for each issue, check BNCs and voltage and amps at camera.

4. Lines on the picture: Depending on the lines you see on the picture this could be attributable to:

a. Ground loop (horizontal line, normally scrolling shadow lines) - Check phases and if necessary change power point.

b. Low power (horizontal line, with colour change in lines, but different from a) - check power ratings with a multimeter.

c. Noise (horizontal line, normally 0,5 mm thick scrolling) - check cable run and BNCs.

d. Induction (vertical line) - check cable run, power cable too close.

5. Static electricity: Unexplained errors, DVR crashes every time you touch it, software jumps, etc. A recent client discovered a static electricity problem; walking 5 m on a nylon carpet gave him an average of 60 000 V charge and this then discharged when he got within 6 cm of any grounded surface, in this case the DVR - resulting in a crashed DVR anytime anyone wanted to use it! Check all anti-static measures and if necessary lay down additional anti-static matting.

6. Slow performing DVR: On the Win 98/ME operating system, several weeks after the DVR installation your client calls to moan that the DVR is very slow and not appearing to perform, as it should. You have a problem with fragmented files on your hard-drive and need to restart the DVR, if the problem persists run scandisk (Win 98 or ME) and then carry out a disk defragment - this will take a number of hours. If you cannot resolve you will need to reformat the hard-drive and lose all data.

7. Insufficient airflow: This will cause your DVR to close down and then restart at a later time, to hang or to close individual programmes. Solution is to mount the DVR where it can get a reasonable airflow, preferably in a cabinet with good all round clearance and with sufficient extractor fans, or in a 24 hour air conditioned environment.

8. Remote, LAN, WAN, dial-in, etc set-ups: Most DVRs supply a manual with key data, which needs to be followed accurately. Some more specialised systems have F1 help keys and detailed manuals and support documents loaded on to the C: drive. It is important to work through the steps in the information given; otherwise you will spend a lot of time calling for more information. In other words Read the key data!

9. DVR still has problems with closing programs, hanging or repeated unexplained shutdowns: You more than likely have a hardware problem with either power supply or RAM. Your first test is to replace RAM, as it is the easiest, secondly in your BIOS check PC health voltage status. Ensure that:

a. v-core does not exceed 1.7v or lower than 1.65v.

b. 3.3v line must not exceed 3.4v and minimum 3.2v.

c. 5v line must not exceed 5.25v and 4.9v

If any of the above is a problem replace power supply.

Please note that these views are not necessary those held by the association. But are a contribution from an association member.

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