Its important to decide the purpose for which the camera will be used for :

Note : General Purpose Monitoring and Face Recognition CANNOT be done with a single equipment. General Purpose monitoring: If the requirement is general purpose monitoring, then you DO NOT need a very High TVL camera. You just need a camera which will do the Job. Any CCD camera above 480 TVL and below 600 TVL will do the Job for you. The Lens required would be around 3.6 MM which would cover 92 degree wide angle.

Face Recognition : For this purpose, you would need a Good camera with a Higher TVL and also higher lens focal. If the camera has to be fitted on a ceiling of normal height, you can use a 6mm lens that will cover a distance of good 10-15 meters and the angle will be narrow hence resulting in better clarity.

Various Digital Video Recorders (DVRs) are available in the market ranging from 4 Channels and goes upto 32 channels. The DVRs are available in various configuration and channel sizes.

The Bifurcations are as follows:
4 Channels
8 Channels
16 Channels
32 Channels

Number of Channels means the number of cameras can be attached to a particular DVR.

Size and Number of Days for Recording : This is indeed a very important question and the way it can be answered is mathematical. At a certain Frame Per Second (FPS- The Speed at which the motion of the camera is recorded), certain megabytes on the Hard drive installed in the DVR is consumed. So the Frame rate is directly proportional to the number of days the data will be stored for.

For Example:
For 16 Cameras :

Normal CIF Quality

1 Tera Byte Hard Disk will record 15 days of data @ 15 FPS.
1 Tera Byte Hard Disk will record 7 days of data @ 30 FPS.
2 Tera Byte Hard Disk will record 28 days of data @ 15 FPS.
2 Tera Byte Hard Disk will record 14 days of data @ 30 FPS.

Half D1 Quality

1 Tera Byte Hard Disk will record 10 days of data @ 15 FPS.
1 Tera Byte Hard Disk will record 5 days of data @ 30 FPS.
2 Tera Byte Hard Disk will record 15 days of data @ 15 FPS.
2 Tera Byte Hard Disk will record 7 days of data @ 30 FPS.

Full D1 Quality

1 Tera Byte Hard Disk will record 7 days of data @ 15 FPS.
1 Tera Byte Hard Disk will record 3 days of data @ 30 FPS.
2 Tera Byte Hard Disk will record 15 days of data @ 15 FPS.
2 Tera Byte Hard Disk will record 7 days of data @ 30 FPS.

Wires play a very important role in the whole CCTV installation process. Wires are available in different types and various aspects decide as to what kind of wires are to be used in the installation.

Generally, in all the CCTV installations the power to the cameras are given from the source where the DVR is installed. The Power to the cameras are given in Amperes and the strength of the power supply depends on the distance at which the camera is installed from the DVR.
There are 2 Types of Wires which are generally used in CCTV installations :
1. 4+1 (1 core Video and 2 pair extra) or 3+1 (1 core Video and 1pair and 1 core extra)
2. RG6 Wires with Separate Power Wire

4+1 or 3+1 Wires : We generally recommend 4+1 wires for longer durability and safety.
Where it is used : If the distance between the DVR and the Camera is less than 55 meters, we recommend using a 4+1 wire. As the name suggest that it has 1 core video and 2 pairs extra. Out of the 2 pairs, 1 pair is used to pump power to the camera from the source. (where the DVR is kept.)
The other pair can be used to attach a Microphone incase voice recording is needed.

NOTE: Voice recording is NOT a feature of an Analog cameras. Its is just a microphone installed separately. (Show a picture of the microphone)

Why a 4+1 wire is not recommended for more than 55 meters is because power pumped in from a distance of more than 50 meters distance drops till it reaches the camera. One power supply is used to power at least 4 cameras. So if One camera is installed at a higher distance, then the power required by that particular camera will be more hence resulting in loss of power to other cameras.

Types of 4+1 Wires :
Local Chinese wires: Ranging from INR 5 to INR 12 per meter.
Branded Indian – KP Plast, Finolex, Ploycab – INR 19-INR 43 Per meter.

In this Kind of architecture the power to the cameras can be given from the source or junctions can be created at various points to ensure that the power is distributed to the cameras evenly.

In an analog CCTV system, its mandatory that each signal cable should come directly to each channel of the DVR. We prefer NOT to have joints between the cameras and the DVR as it results in signal distortion, poor picture quality and heavy maintenance.

Hence when we quote for the wiring and installation for projects, wastage is also taken into account.

Various Kinds of Wires available In the market:

– Local RG6 – very poor quality – ranging from INR 6 per meter
– RG6 (CCS) center core Steel- In the cross section of this type of wire, you would see the center core looks like copper, but its steel. Hence reducing the cost of the wire – average price – INR 9 to IR 13 per meter.
– RG6 copper – The center core of this kind of wire is copper. But NOT 100%. Upto 67% copper is a market standard. Price ranging from INR 19-INR 31 per meter (depends upon the brand.)

Second comes the breed of the wire guage inside the wire which surrounds the copper core. The Higher the density of the mesh (How closely they are held) decides the price of the wire.

Why its Important: You may use the best of the Cameras, but if the wires are average, you may not expect the result of the cameras to 100% because the signal transmission depends of these wires which carry the signals from the camera to the DVRs.

Design considerations. Typically, a fire alarm system is made up of the following components:

Initiating devices, capable of placing the system in the alarm state. These can be photoelectric smoke and heat detectors, ionization smoke detectors, heat detectors, in-duct smoke detectors, manually operated pull stations and sprinkler waterflow sensors.
Indicating appliances, whose purpose is to announce builidng occupants or at a remote location when the system enters the alarm state, such as horns, strobe lights, chimes, bells, or combination units. They are also available in weatherproof and hazardous location versions.
A control panel, containing programming and operating electronics and user interface, is fed by standard branch-circuit wiring and contains replaceable circuit cards — one for each zone. This includes an alphanumeric display, showing the state of the system and providing troubleshooting information, and a touchpad so that onsite personnel can silence an alarm or trouble signal, reset the system following an event, and reprogram if necessary
Sealed batteries similar to emergency light batteries, but listed for fire alarm systems. These are usually 6V batteries wired in series to make up 24VDC for a power-limited system. The batteries can be contained in the control panel or in a separate enclosure. When AC power fails, the batteries take over with no interruption in fire protection. Of course, there is also a charger.
Auxiliary devices, including remote annunciators with LEDs showing the state of the system, an alarm silence switch, and visual LED indication of the zone from which a fire alarm is initiated. Electromagnetic door holders (floor- or wall-mounted) are available. In case of alarm, the magnet is de-energized, allowing the door to swing shut. Later, it is reopened manually.

Initiating devices are connected to the control panel by a 2- or 4-wire initiating device circuit. In the case of a power-limited system, 24VDC is applied to two wires going to a string of initiating devices, which are wired in parallel. Neither wire is grounded, and they are isolated from EMT or other raceways, which are grounded through the connector at the control panel. Polarity is also critical. This voltage is used to power the solid-state circuitry within each detector. It’s also used by the control panel to monitor the state (alarm or no alarm) of the initiating devices and zone wiring.

A typical fire alarm system has numerous initiating devices divided among separate zones — each connected via an initiating device circuit to a central control panel. The control panel performs supervisory functions over the initiating devices, indicating appliances, all associated field wiring, telephone ties, and its own internal wiring and circuit cards.

Installation tips – During initial setup, all zone wiring, initiating device, and indicating appliance installation should be completed before the telephone tie is hooked up, typically by means of a ribbon connector. This is so that the monitoring agency won’t receive false alarms.

The control panel should be located where it can be responded to as necessary either around the clock or during operating hours. This can be at building security headquarters, adjacent to a telephone switchboard or in a maintenance office — whichever location offers maximum coverage. It should also be positioned in a fairly central location because if the system goes into alarm, a person needs to be able to race to the location and verify fire status before the alarm is silenced.

Operational issues – A fire alarm system operates in one of three (or more) states: normal, alarm, and trouble. The state is reported at all times on the alphanumeric display. If the system goes into alarm, the indicating appliances throughout the building go off. These could be very loud horns for some occupancies, or softer chimes in others, such as a nursing home.

The control panel monitors the initiating device circuits at all times for shorts and open wiring by means of the applied DC voltage. The initiating devices are normally open. In the event of a fire they become conductive at close to zero ohms. How, then, is it possible for the control panel to differentiate between a non-alarm state and an open wiring fault? This is accomplished by means of an end-of-line resistor.

A 4.7 kilohm (typically) resistor is placed across the line after the final device. When this resistance is seen by the control panel, normal status is maintained. If the resistance increases, it means that an open has developed, and the panel goes into the trouble state. A buzzer sounds to alert maintenance personnel but the much louder horns throughout the building do not go off. The alphanumeric display will read something like “Open Circuit in Zone Three.” The trouble alert can be silenced by pressing a touchpad location under the trouble alert LED.