Introduction to CCTV System

• A CCTV system is a television system, which operates on a closed loop basis.

• The main function of the CCTV system is to allow surveillance and remote viewing.

• Usually, it is a part of an overall integrated package. • Through these systems some of the on-going

hazardous processes are being monitored remotely from the control rooms.

• This is the only on line visual communication in the plant.

Existing CCTV System

• The simple system is a camera connected directly to a monitor by a coaxial cable.

• The camera generally mounted on a fixed platform or movable platform.

• The camera converts the optical signal into electrical signal (composite video signal) and at the TV end the electrical signal reverts into optical (video) signal.

The above indicates only the main constituents. The actual system may contain a combination of several accessories.

BLOCK DIAGRAM OF EXISTING CCTV

These are mainly, Plan and Tilt drive unit. Video Switcher. Video distribution amplifier. Protective housing. Cooling Jacket and Vortex Cooler.

Pan and Tilt drive unit:

• Pan and Tilt drive unit are used for remotely controlling the position of cameras.

• Using limit switches (individual for the P&T), the angular travel can be controlled.

• These limit switches are adjusted in the site in such a way so that the camera can move up to the desired area of observation.

Video switcher: • In a multi camera system video switching

facility is employed.• The 8 x 1 video switcher accepts eight

different video signals and selects any one at a time.

• The electronic video exchanges are microprocessor based and are user friendly.

Video distribution amplifier:

• The output from a single camera can be displayed on several monitors.

• The distribution amplifier also compensates for the loss of video due to increased length of cables.

• The unit requires 230VAC power for its operation.

Protective housing:

• In some cases camera are placed in some rigorous environments where temperature, dust, vibration humidity etc.

• This protective house is chosen in such a way that the camera, lens, power supply unit etc, can be accommodated in the housing.

• The front portion of the housing is made of special glass.

Cooling Jacket and Vortex Cooler:

• To protect camera from high temperature cooling jacket is used.

• For this type of housing one water inlet and one water outlet are there.

• Vortex cooler enclosure cooling systems is also used.

• Vortex converts compressed air into cool, filtered air without using refrigerants.

A four-camera system with video switcher

Lens

• It is fixed in front of the camera and is used to focus the required object.

• The specification of CCTV lens contains parameters like format, focal length, iris control, focus control and voltages in case of zoom lenses.

• The selection of lens mainly depends on the camera size, area of coverage and place of use.

Multiple Camera System

Conversion of analog cameras to digital

• For the conversion of Analog cameras to a Digital one a particular device named as DIGITAL VIDEO RECORDER is used.

Digital Video Recorder:

• DVRs were introduced marking the evolution of the second generation of CCTV.

• The beauty of the mechanical device was that it was something anyone could operate.

• The DVR allowed a video to be recorded in higher resolutions than VCRs and eliminated video tapes.

Video over IP Analogue image to Digital image Transmission process:

• The NTSC video signals from analog cameras are connected to video capture cards inside the DVR APPLIANCE OR PC.

• The capture cards take the analog signal and digitize it.

• Stored on a hard disk or a multiple disks. • The DVR software then allows the user to

monitor live cameras.• Connect remotely to the main unit via the

network.

CCTV SUGGESTED SYSTEM

• The proposed system would contain black & white and colour cameras.

• By assigning unique IP addresses to these digital devices on the Ethernet.

• The digital cameras utilize Super Dynamic function to capture natural images.

• In addition, this colour camera can also control external devices.

• The camera is designed for monitoring over a WAN or over the Internet a snap.

ANY

QUIRIES…?

ANY QUIRIES…?