Welcome to the
"Technical Section"
of
Doktor Jons

Guide to Closed Circuit TV (CCTV)

TRUSTED - Target Recognition Using Surveillance Technology for Evidence and Detection - A campaign to improve the effectiveness of existing video surveillance security systems.


CCTV Camera Operation - in a little more detail (continued)

- Television Scanning Systems & Power Supplies -


So whilst we now know that CCIR and EIAJ refer to the actual make up of the image (as you've probably guessed, they are not compatible!), we can now look at 'PAL' (which is the colour standard used in the United Kingdom, and various other countries around the world); 'NTSC' (which is the colour standard for the Americas & parts of Asia), and 'SECAM' (which is the standard for France, parts of Europe and again, various countries around the globe.

Guess what, not only are the three standards incompatible, but .... and you're going to love this bit .... there are actually country specific variations of each type.

For the moment, don't worry too much about these standards, as Doktor Jon will explain more after the next specific factor, which is the CCTV cameras ....

Power Supply

If the unit is intended to be powered from the mains electricity supply, then quite obviously it should be capable of operating on that specific voltage (obviously, the same principle applies to any item of electrical equipment).

So for example, the mains supply in the United Kingdom is 240v AC 50 Hz. ('Hertz' - used to be known as 'cycles per second'), in some parts of Europe it's 220v AC 50 Hz., and in the United States it's 110v AC 60 Hz.

Nowadays, many cameras operate on much lower voltages, either 24v AC (make sure it's manufactured for the correct 'frequency' e.g. 50Hz.), 12 v DC which is actually a very flexible option (more about 12v later), and even occassionaly 'line powered' where the cameras power supply is carried up the same co-axial cable as the video signal.

With this type of camera, it is of course essential to make sure that the power supply unit or adaptor, is designed to operate from the available mains voltage.
 


More about CCTV camera power supplies>

IMPORTANT: No material may be reproduced, copied or redistributed from this site,
without the express written consent of doktorjon.co.uk

All the detailed information on this site is provided in good faith; and as such, Doktor Jon
does not accept responsibility for any consequential loss, injury or disadvantage
resulting from any individual or organisation acting on the details contained herein.

© doktorjon.co.uk 2004 - 2008

Homepage...:...Gateway...:...Technical Gateway....:....Quickfind Index....:....Equipment Directory
Site Index...:...About this site....:....CCTV Helpdesk....:.... The Forum ....:....Contact Doktor Jon