Smart sensor technology – definitions of the most common terms

  • Share

Smart sensor technology – definitions of the most common terms

We try to keep jargon and technical language to a minimum on our site, but the nature of what we do means using some terms not everyone will be familiar with. Whether you’re new to the world of smart building management or you’d like a quick refresher, you’ll find definitions of some common terms below.

Smart-building sensor technology

The A-Z of smart-sensor technology


An actuator receives the signal from the sensor, gateway or controller and acts on it – perhaps by switching off a light or adjusting the heating or ventilation. It lets you automate control of local systems with minimal impact on your IT operations.



Stands for Application Programming Interface. An API is a bit like a messaging service – it allows two applications to talk to each other.

We found a helpful example here (and the video is worth a watch too). Say you’re looking at flights online and want to compare airlines to find the best option. The site’s API sends your request to a number of airlines’ databases, then gathers their responses and presents them back to you.

In our sensor systems, our smart gateway converts selected data to a usable format and sends it to your cloud system or internet-of-things platform using secure APIs.



The use of systems to operate equipment or machinery with minimal or reduced human input – for example, a heating system that switches itself on when it detects a low temperature.


Energy harvesting

Energy-harvesting sensors or switches work by collecting tiny amounts of energy – such as light, temperature differences and kinetic motion – from their environment. It means they use very little power and require virtually no maintenance.



A gateway receives signals from the sensors and makes it usable. It converts the data into industry-standard formats, which means it can be securely integrated into any software or platform.



Stands for Internet of Things, a term used to cover internet-connected devices or objects that ‘talk’ to each other by gathering and communicating data. That could be anything from a temperature sensor to a fitness tracker, a security camera that sends alerts your phone, to an egg tray that helps you avoid home-baking disasters. IoT-enabled devices are often described as ‘smart’.


PIR motion sensor

PIR stands for Passive Infrared. Each motion sensor has two slots made of a material that’s sensitive to infrared light. When the sensor is idle, both slots detect the same amount of ambient infrared radiation. When a person enters the sensor’s field of view, the movement reaches one half of the sensor before the other. It’s this change between the radiation detected by the two slots that tells the sensor someone is present.



Repeaters, gateways and actuators are all types of receivers – components that receive the signal transmitted by the sensor.



A Relay is a type of switch that’s controlled by electricity. They can be switched on or off by the presence of a relatively small electric current, and in turn, can switch on another appliance using a much larger current. This is useful for us because sensors only produce a very small current, but often we need them to drive bigger pieces of apparatus that use bigger currents. That means relays can work either as switches, turning things on and off, or as amplifiers, which convert small currents into larger ones (source).



Repeaters are used to increase sensors’ range, allowing them to transmit data over a larger distance or work around obstructions.



Our sensors are small wireless boxes that simply stick, click or screw to your chosen surface. They work by detecting changes in conditions and sending the information they gather to a receiver – which could be a repeater, gateway or actuator – via radio signals.



A smart object or device is one that can interact with people, the environment or other objects. It’s a word that’s often used to describe devices connected to the Internet of Things.



A switch is a control that’s operated by the user and can be as simple as switching a light on or off.


Did you find what you wanted to know? We’ll add to this list in future, so if there’s a definition you think we should add, just let us know.

  • Get smart building insights

  • Find out more

    If you’re looking for a partner who understands technology – and offers reliable, cost-effective solutions in high volumes – get in touch.
    Call us: +44 (0) 115 936 5200

Want to learn more?

Download our brochure to see what our technology could do for your business.


You have Successfully Subscribed!

Digital twin of smart buildingsPlanning your wireless sensor system using floorplans