This article helps you to specify a CCTV system; the intended audience for this guide being either an installing company or an end user. You should be aware there are many types of CCTV systems available on the market; these range from cheap cctv systems for basic monitoring, best value security camera systems for some form of identification and to high resolution security systems that lead to identification and prosecution.
A good security camera system will offer best value for money without compromise on the quality. There are many products available on the market which makes it very difficult to identify what products are suitable for your requirement. Sometimes, it is equally difficult to identify areas that are vulnerable and a suitable cctv camera to target that area. Most people forget that a cctv camera system is a long term investment and they should discuss their requirements with a technical sales person before they make the purchase.
Understanding cctv terminology can also be daunting, see our FAQ section for more details.
Understanding your Security requirements
Main reasons for your requirement of cctv security cameras will reflect the type of system you need. Some of the reasons for needing a security system could be:
– Shop theft
– Shop or home break-ins
– Industrial espionage
– Danger to individuals from attack.
– Health and safety of individuals on the premises or site.
– To replace or reduce manned guarding.
– To supplement manned guarding, making them more efficient.
– To monitor persons entering and leaving the premises.
– To provide visual confirmation of intruders activating an alarm.
– To monitor a remote, unattended site.
Reasons for a system could be endless, but for a particular site, there will finite reasons for considering CCTV. If they cannot be listed, you probably don-t need it.
What is the possible solution-
Once a problem is understood, the next step is to find how a solution can be achieved. The solution could be in many forms – it could be an intruder alarm system, some form of deterrent (lighting, fencing and gates), a cctv system or manned guarding. Your need will depend on the circumstances and requirements on any particular site, but it is important to at least make a list and consider all the possibilities. Some options maybe impracticable and others maybe too expensive but you should finish up with a short list of possibilities. Quite often, the solution will point to a cctv system as this will be cheaper and more affordable.
Decided that you need CCTV Systems-
Before selecting the type of cctv system that will fulfill your requirements, you should consider; the type of cctv cameras you need, how you will monitor the system, will you require network access (remote internet access) and cabling.
Type of cctv cameras you need:-
Colour cameras generally require a higher level of lighting than their Black & White counterparts do. Colour cameras give the advantage of being able to easily distinguish and detect objects simply by their colours where Black & White cameras offer better resolution in low light conditions.
– Covert cameras. These cameras are so small they cannot be easily seen or are disguised as a different device (such as smoke detector, PIR etc).
– Day/Night cameras. These cameras switch from colour to black and white depending on lighting levels. They are ideal for variable lighting conditions.
– Night Vision cameras. These cameras have their own light source in a light spectrum that can’t be seen by the naked eye.
– Outdoor cameras. These cameras have hardened, waterproof outer bodies.
– Speed Dome cameras (Pan, Tilt, Zoom). These cameras allow for remote control of what the camera is pointed at and what it is focused on.
– Vandal Proof cameras. These cameras come in hardened cases that can resist physical abuse.
How you will monitor the cctv system-
– Main Output- Most CCTV DVRs have composite video output which can be viewed on standard TV Monitors (like AV input or SCART input)
– Spot out / Call output- This output is also composite Video which can be used to monitor cctv cameras in full screen mode in sequence.
– VGA output- this output is standard output used on PCs. Any VGA TFT LCD monitor can be used.
Network Access / Remote Access- CCTV DVR Access over the internet (broadband)
– Internet Access- Most CCTV DVRs now days have remote access via the internet
– Simplex- DVR can only perform either record or play back but cannot perform both simultaneously.
– Duplex- DVR can only perform two things simultaneously (record, play back or remote viwing but not all three simultaneously).
– Triplex- DVR will perform all three things simultaneously (record, play back and remote playback)
– Pentaplex – cctv DVR can carry record, playback, remote access, remote playback.
What type of cctv cables are there-
– Pre-made leads- these are pre-fabricated leads with BNC and power connectors already terminated on the cable. Very simple to install, no real skill required. These leads are design to carry low voltage (12V DC) upto a distance of around 35m. Distance greater than 35m will cause picture corruption with the camera.
– Local AC power – where the distance is greater than 35m, if cameras are powered locally, you can cover much greater distances. For distances upto 100m, RG59 coaxial cable could be used.
– Combined Coaxial cable with power- RG59 coaxial cable but 2 core power cable attached (like a Shotgun).
– CAT5E- Longer distances can be covered CAT5E in-conjunction with passive transceivers.
Selecting the most suitable cctv system is a compromise between the quality, area you want to cover and the overall budget. It is advisable that you have in-depth discussion with the technical sales person before you select the security cameras or the diy cctv system you need. A good technical person will try to understand your need, explain the difference between the various cctv cameras before any recommendation.