CCTV Dictionary – What is all this terminology?

In the CCTV industry there are lots of terms that you may have never heard of. Following is a dictionary of common CCTV terminology.

If you can’t find a term here, you are welcome
to post it as a comment for us to research it.

Baseefa Certification

When electronics is used in areas that have a high risk of explosions occurring, you need to put the cameras in a Baseefa Certified camera housing – this may also be referred to as  intrinsically safe  – which prevent any spark inside the housing from triggering an explosion.

CCTV

The acronym stands for Closed Circuit TeleVision and literally refers to the fact that every camera is connected via a closed circuit – typically a coax cable – to a monitoring point.

While we still refer to IP CCTV as a CCTV system, it is not really as it is not a closed circuit as the IP network can go anywhere.

CCVE

Almost the same as CCTV but is the acronym for Close Circuit Video Equipment

DNR

Digital Noise Reduction – the cameras ability to reduce the electronic noise that appears in a camera during lower light conditions.

DVR

A Digital Video Recorder is a device that can record one or more – typical;y 4, 9 or 16 cameras – to a hard drive.
Unlike a NVR, the cameras are physically connected to the recorder. However there are some units called Hybrid DVR’s, which are a combination of a NVR and DVR

FAT – Factory Acceptance Test

The aim of a factory acceptance test is to demonstrate that the individual pieces of electronic hardware in a system actually work together as one complete system and meet the compliance requirements, typically defined in a tender document.

Intrinsically Safe

When electronics is used in areas that have a high risk of explosions occurring, you need to put the cameras in an intrinsically safe camera housing – this may also be referred to as  Baseefa Certification – which prevent any spark inside the housing from triggering an explosion.

IP

Internet Protocol

IP Camera

A modern type of CCTV camera that uses a computer network to transmit its video instead of the more traditional coax cable. The advantage being you can use the existing computer network infrastructure instead of needing to run a new cable from every camera to a central location.

IP CCTV

A CCTV system that used the IP computer network to transmit the captured video between the IP camera and the recorder (NVR)

IP Rating

Standing for Ingress Protection, it is a rating that has two digits that specify the ability of an object such as a camera housing to stop the ingress of solids – the first digit – and liquid – the second digit. See the post on this topic – IP (ingress protection) rating

IR Illuminator

IR is an acronym for Infra Red, a light wavelength from 740 nm (nano metres) to 300 µm (micro metres).
At the 740-880 nm range, the light is only visible if you look directly at the light source but no visible light is cast on the ground. This is why you can see a dull red glow from many security cameras. Using an IR illuminator in the 940 nm range will not be visible to the human eye even if you look directly at it.
A word of warning:  High power infra red can be harmful to the human eye. Because our eye cannot see it, the iris does not close down as it would to a bright light in the visible spectrum, resulting in a burning or itchy eye feeling when looking directly at the light source. This was more problematic with the older types of illuminators before LED lights became the norm.

Lens

The lens on a CCTV camera is in principle the same as on a digital camera but typically smaller. CCTV lenses come in common format sizes including the most common 1/4″, 1/3″ but also 1/2″ and 1″. Matching the lens to the camera is a reasonably important factor.  A lens with a smaller format than the camera will result in the edges of the image being cut of and displaying as a black circle. A larger lens is in most cases fine but can have a small negative impact on the cameras low light performance. Every lens has its focal length measured in millimetres (mm) – yes even in imperial America – and its light performance – aperture – is measured in f-stops. There is also a measure of the lenses maximum resolution when attaching it to a mega-pixel cameras.

NVR

The Network Video Reorder that is used to record IP cameras over a computer network

Spot Monitor

A spot monitor is used in a CCTV system to display either a single camera or a sequence of cameras.

Typical applications include a monitor showing the footage of yourself as you walk into a petrol station or supermarket. It may also be used to display a specific camera only when an alarm has been activated to draw it to the attention of a security guard in a security control room. In this application it may also be called black screen monitoring because the monitor remains black (no signal) until an alarm occurs, which draws immediate attention to the monitor.

While it’s meaning originates from the less flexible analogue CCTV, it is still referred to in more modern IP CCTV systems. However in modern IP systems, the spot monitor is more likely to be a much more flexible in its capabilities and may be able to display multiple cameras on the one screen or even allow video playback.

VMS

Video Management System – The software that the acts as the user interface for ans IP CCTV system. Well known brands include MileStone, Genetec & IndigoVision