Understanding Alarm System Jargon – Our Simple Guide!

CTB Alarms Blog

Getting your home security sorted can get technical and whilst some people thrive on technology and like to understand how it all works, others find it all a bit daunting.

Jargon Buster - Security made simple!

At CTB we like to keep things simple and focus on gathering your home security requirements before identifying and explaining potential solutions in clear and simple language, using non-technical terms.

There’s no getting away from the fact that security systems are technical and there are countless acronyms, abbreviations, and technical terms used. There’s also crossover for other technology areas such as the internet, Smart technology, mobile phones, etc. There will be words or terms that you may have heard used in everyday conversations, but you’ve felt uncomfortable admitting that you’re not entirely sure what it means. Some of these may crop up when you are researching home security, engaging with an alarm company about a new alarm system, or getting an existing burglar alarm upgraded, serviced, or repaired.

CTB Alarms are experts in the home security industry and it’s our job to take care of and to understand the technical aspects of installing, maintaining, and repairing home security solutions. If you want to get technical, we’re happy to share the details with you but in our experience, the majority of our customers have called professional alarm installers because they want to use our experience, expertise, and technical knowledge.

To help you with the technical stuff we’ve tried to think of the technical terms, jargon, abbreviations, and acronyms for the alarm system and security industry and we’ve provided explanations and definitions for you, so hopefully, they are slightly easier to understand.

Please see below our glossary of terms for security and security alarm systems. Security made simple!

‘Smart’ Technology

The word ‘SMART’ stands for ‘self-monitoring, analysis, and reporting technology’. Smart technology is a technology that uses artificial intelligence, machine learning, and big data analysis to inanimate objects to provide them with cognitive awareness. Examples of Smart technology include Smart Connected Devices, Smart Devices, and IoT devices.

Duress Code

A code is chosen by the user which can be entered when they are under duress to request assistance without alerting the intruder. If you were faced with a request from an intruder in your home to disarm the alarm system you would enter the duress code and this would appear to disarm the alarm, however, it will also send out a request for emergency help.

Entry/Exit Zone

These areas usually include front doors, and/or back doors, and garage doors. Entry/Exit Zones are the areas most frequently used to enter the property. For home security these.

Alarm Battery

An alarm battery is a battery used in a wireless alarm device or security system control panel. These may be alkaline alarm batteries though generally, Lithium alarm batteries last longer.


An armed system is an alarm system that is switched on and actively monitoring for triggers. A disarmed alarm system turns off monitors which means you can move around freely without setting off the alarm.

AC Power

The alternating current which is supplied from a plugged-in transformer.


A forced entry into a secure property. Generally, a burglary will result in the damage or theft of property.


Designated areas within the home that are protected by a motion sensor. A property can be split into multiple zones. Some zones can be armed, and some can be disarmed. For example, you may wish to disarm the zones in the upstairs of your home at night, so you don’t set off the alarm if you get up to use the toilet.

Motion detector

A device that detects movements. Types of motion detectors include Active Infrared Detector (AIR), Passive Infrared Detector (PIR), Microwave Motion Detector.

PIR Motion Detectors (PIR)

PIR Motion Sensors are often referred to as ‘PIR’ which stands for ‘Passive Infrared’, ‘Pyroelectric’, or ‘IR motion’ sensors. PIR sensors work by detecting infrared light given off by a moving object or person that emits heat. PIR sensors sense motion and are most often used to detect whether a human has moved in or out of the sensors range.

Alarm Key Holders

The keyholder is the person who is will be notified when the alarm is triggered. There can be more than one key holder. The keyholder will be notified by phone or text if the alarm is triggered. For monitored alarm systems this may be in addition to notifications made to a professional monitoring company and/or the police. The alarm keyholder is most commonly the home or business owner and the person that has responsibility for the property.

Active Infrared Detector (AIR)

An Active Infrared Detector requires both an emitter and receiver to both emit and detect infrared radiation. The emitter is a light-emitting diode (LED) and when an object comes close to the sensor, the infrared light from the LED reflects off the object and is detected by the receiver. This, in turn, triggers the alarm.

Microwave Detector

A motion detector that emits microwaves. When the microwaves encounter a moving object, some of the microwave energy is reflected and triggers the alarm.
Microwave detectors are an alternative to a PIR motion detector and are ideal for extreme environments where a PIR would be ineffective. The reason for this is that a microwave detector will not be triggered by temperature, sound, light, or vibration.

Pet Immune motion detector

A pet immune motion detector or pet-friendly alarm motion sensor has the capability to distinguish between and ignore an object or animal of a certain size, e.g., up to 36kg. This will reduce the number of false alarms that occur because the cat or dog crossed the room! Pet-friendly alarms systems usually operate by lowering the sensitivity of a motion detector, so a large object or person needs to be present to trigger the alarm.

Pet Friendly Alarms

See also ‘Pet Immune motion detector’. A pet-friendly alarm is an alarm that can differentiate between the body mass of human, and that of a cat or dog. If your pet is going to be home alone when the alarm is armed and moving around then you will need to ensure your security alarm is pet friendly.

Entry/Exit Delay

A short delay for you to enter/exit the premises. On entry, you will enter the property and have a specified number of seconds in which to disarm the alarm by entering the correct code. If the code is not entered the alarm will sound. On exit, you will arm the alarm system and have a specified number of seconds to exit without setting the alarm off.

Night Set Mode

Night Set mode is an alarm setting available to you which allows you to arm certain areas of your home to allow for your nighttime routine. Commonly this setting will arm the downstairs of a property whilst allowing you to move around freely upstairs during the night for example, to visit the bathroom or care for a young child.

Hard Wired alarm system

A hard-wired alarm system consists of one or more alarm sensors that are connected to a main alarm control panel with professionally installed wires. Hard wired alarm systems use a fixed connection to work and carry out their communication and the wired connection is used for all communication between the components of the alarm system.

Wireless alarm system

A wireless alarm system protects a property from break-ins, theft, fire, and other emergencies. A wireless alarm system is a home security system that uses wireless sensors placed around doors and windows throughout the home. These sensors are used to detect intruders, and if detected they will trigger the alarm. Wireless alarm systems remove the need for the installation of wires throughout the property which can be problematic and untidy.

Control Panel (often referred to as an alarm keypad)

A control panel is a device that is usually installed on the wall internally and gives the controller or homeowner access to the functions of the alarm system. The control panel can feature a simple keypad, a touchscreen panel or it could be a mobile app-controlled device. The control panel Is used to arm and disarm the alarm system, shows the alarm system status, is used to adjust settings, or add new security devices, sends the message to sound the alarm when it receives a transmission from an alarm sensor and in the case of a monitored alarm is communicates with the monitoring centre.

Bullet Cameras

A type of security camera that is suitable for indoor and outdoor use. Bullet cameras are one of the common types of security cameras and they get their name from their shape, which looks like a bullet shell. Bullet cameras point in one direction, have good range, and are suitable for viewing large areas and a fixed specific location. This means they are good for outdoor use, for example for carparks, yards, and outside storage. Indoors they may be used in a reception area or pointing at an entrance door. Bullet cameras are easy to install and are a visible deterrent.


CCTV is an acronym for Closed Circuit Television. CCTV is a camera system and is commonly known as video surveillance.

Door Contacts and Window Contacts

Door contacts and window contacts are small devices or sensors fitted to windows and doors which notify your alarm systems when the door or window is opened or closed. There are various types available, surface mounted contacts, recessed contacts which are not visible as they are hidden in the door jam or window track, roller ball contact, and overhead door contacts which are used in the case of certain garage doors.

X10 System or X10 Device

X10 technology uses your home’s existing electrical wiring to remotely control security systems, appliances, light, and much more. X10 remote control, switch, and module commands travel from X10 transmitters to X10 receivers through standard household wiring which means no new wiring is required.

Two-Way Keypad

A two-way keypad is a device that allows you to arm and disarm an alarm system from inside or outside a property.

Alarm Back-up Battery

An Alarm Back-Up Battery is activated once AC Power is lost. If for any reason AC Power to your alarm is lost the backup battery will activate and keep the alarm system running for a short amount of time until AC Power is restored. A backup battery will typically keep an alarm system running for up to 24 hours.

AC Power

AC Power is the primary power source for an alarm system and is provided via a plug-in transformer. The transformer plug is plugged into an AC outlet and it ‘transforms’ high-voltage power into low-voltage power that is suitable for powering your alarm system.

Alarm Panel Battery

A battery that powers the main alarm system.

Alarm Bell-box Battery

If you have a live ‘sounder’ or ‘bell-box’ outside your property this will have a ‘back-up battery’. See also ‘Alarm Back-Up Battery’.

Alarm Sensor Battery

A battery used to power wireless sensors. Each sensor will have a battery. It is recommended that Alarm Sensor Batteries are replaced every 18 to 24 months.

Shock Detectors

A shock sensor is a small device that is fitted to a window or door for security. A shock sensor will detect an attack on a window or door, for example, if someone is hitting it, tapping it, tampering with it, or trying to remove the window beading to gain access. When this occurs and the shock detector detects vibration it will trigger the alarm. A shock detector will raise the alarm before an intruder has gained access to a property which means it can scare off a burglar whilst they are attempting to break-in.

Internal Sounders

This is a siren or sounder that goes off inside the property if the alarm is triggered.

External Sounders

This is the alarm siren or alarm sounders that make an audible noised outside the property if the alarm is triggered. Often accompanied by a strobe light. The external sounder is housed in a bell box outside the property in a high-up position.

Alarm System Takeover

An Alarm System Takeover involves taking over the responsibility for the ongoing maintenance of an intruder alarm system from the company who originally installed it. This will include alarm service, repairs and any enhancements and upgrades. Alarm System Take-overs occur sometimes because the orignal alarm company are no longer able to provide a service or purely through customer choice.

Alarm PIN Code

An alarm PIN code is essentially your password for your alarm system. PIN stands for Personal Identification Number. The PIN code is entered whenever you wish to arm or disarm the alarm system. The PIN code identifies you as a person authorised to access the property or make changes to the alarm settings. PIN numbers should be kept private and only shared with authorised people.

Key Fob / Digital Key

An alarm key fob is a wireless remote control device used to control your alarm system. It often includes a panic button to sound the alarm or notify a monitoring company. A Digital Key can be used in addition to, or in place of an alarm keyfob and uses a smart device such as a phone to control the system. A digital key means you can use your smart device to perform alarm functions, for example arming and disarming the alarm.

Home Insurance Reduction

Some insurance companies will take into account the security systems in place at a property and if certain criteria are met they may apply a discount to the insurance premium.

Monitored Alarm Systems

A monitored alarm system is an alarm that is actively monitored by a professional home security company. When the system detects an intruder it notifies the professional monitoring service. The monitoring company will contact you to establish if there is a genuine incident. If they cannot contact you they will contact emergency responders, such as the police.

Remote Home Security

Remote home security allows property owners to activate and operate their home security system when they are away from the property by using a handheld device such as a smartphone. Depending on the security package selected, remote home security systems can include an alert to your mobile phone by text or a phone call to let you know that your alarm has been triggered. Some security surveillance packages allow access to constant remote monitoring via the web and are connected to a professional monitoring service. In some cases, this can also involve contacting the authorities such as the police or fire service on your behalf if an alert is received.

‘Bells only’

This is the term used to describe an alarm that is not connected to any kind of professional monitoring service and/or the police. If the alarm is triggered the siren will sound. See also ‘Self Monitored Alarm Systems’

Bell Box

A self-contained, tamper-proof enclosure that is mounted externally on a property and in a visible, high-up position. A bell box houses high output two-tone sounder or siren which is usually accompanied by a strobe light. Bell boxes come with backup batteries.

‘Self Monitored Alarm Systems’

A self-monitored alarm is an alarm that is not monitored by a professional monitoring service. If the alarm is triggered the system has the facility to notify you and a specified number of additional keyholders by phone or text that the alarm has been triggered.