10 Must-Have Sensors for a Truly Smart Home
We independently test the products and technologies that we recommend.
1. How a Smart Home Affects Comfort and Safety of Life
The term "Smart Home" is often encountered in modern society, but everyone perceives it differently. Simply put, it is a single system that includes a central control unit and numerous additional sensors of various purposes, which are selected and configured according to user requirements and operating conditions. Such a complex is designed to automate many processes, enhance comfort and safety not only for humans but also for pets, save energy resources, and even conduct agricultural activities efficiently.
2. Main Control and Monitoring Sensors
Manufacturers offer a wide range of sensors for tracking the most important indicators, based on which the smart home makes programmed decisions. Let's get to know them better.
2.1 Motion Sensor
Designed for deploying a security system. The most popular are infrared and ultrasonic operating principles. The first tracks thermal radiation in the infrared spectrum, and the second works like an echolocator. The security motion sensor sends a signal to the central console to activate an alarm, video recording, and secondary precautionary measures—alerting the user and security services about an intrusion.
There are more advanced sensors with a spotlight for illuminating the monitored area in case of activation, which helps immediately identify the intruder. Such complexes are often installed as standalone elements of a security structure or used to create economical lighting around a private house, in café and restaurant restrooms, on highway interchanges. The scope of application is practically unlimited, and solar panels are used for autonomous operation.
2.2 Opening Sensor
Another important component of the security system that will protect the house from intrusion. It consists of two parts—a magnet and a reed switch. The operating principle is based on creating a magnetic field that holds the reed switch in a closed state. The magnet is attached to moving parts, and when removed, the reed switch is opened. The signal goes to the control unit, and the user-programmed protection mechanism is triggered.
It is worth noting that the opening sensor can be used to control and improve the efficiency of the heating or cooling system. For example, when a window is opened, the air conditioner will be turned off.
2.3 Vibration Sensor
Participates in ensuring security by warning about an intrusion attempt. It is most commonly used in conjunction with an opening sensor to eliminate bypassing by breaking glass or other surfaces. It has also proven effective in protecting valuable items. The technical implementation can vary. The main types are piezoelectric, magneto-inductive, optical, and eddy current. The essence of the work is to convert mechanical vibrations into an electrical signal, which is analyzed by the system and compared with the sensitivity settings. In practice, such an approach is not always effective, as there is a high probability of false activations for various reasons (movement of large vehicles or trains, repair or explosive work near the object, human factor, seismic activity of the region).
2.4 Temperature Sensor
Such sensors are quite universal and can perform various functions within a smart home. They interact effectively with climate equipment (heating boiler, air conditioner, recuperator, convector) and participate in fire prevention systems.
It should be noted that there may be several such sensors for comprehensive safety and comfort. These modules are often combined with other popular humidity and pressure sensors to create ideal indoor climate conditions. Another direction is agriculture (egg incubation, seedling cultivation, floriculture, selection).
2.5 Humidity Sensor
It is almost never found as a standalone device and is part of various climate complexes. Based on sensor data, a smart home can launch a dehumidifier, humidifier, air conditioner to maintain optimal parameters and prevent health problems.
2.6 Light Sensor
A very common element that operates not only as part of a smart home but also as a separate module. The device is based on a photoelement that measures the level of external illumination, and when the set threshold is reached, it closes/opens the circuit. The main task of the sensor is to turn on street lighting in the evening, although in practice it can be adapted for many tasks (activating irrigation or special lighting in greenhouses, water heating devices, decorative lighting outside and inside the premises). Many modern sensors support sensitivity threshold adjustment for more precise adaptation to the tasks at hand.
2.7 Smoke Sensor
A safety tool for timely detection and prevention of fire-hazardous situations. This device's design includes a special chamber with an opto-electronic module that triggers when smoke enters. As part of a smart home, the sensor can send a signal to the control unit to alert the relevant services or activate an extinguishing system if it is provided. Modules are usually supplemented with local sound alarms.
2.8 Gas Sensor
Another control tool that can detect different types of gas in the air—carbon monoxide (CO₂), methane, propane, butane. The sensor is an effective addition to smoke and temperature detection and helps prevent explosive situations due to the accumulation of a large concentration of natural gas. The housing is usually equipped with a speaker for sound alarms and a display for visual control. It is installed in places where communications are connected and cooking is done. The device works optimally in tandem with an automatic shut-off valve, which cuts off the domestic gas supply in case of a leak.
2.9 Leak Sensor
A simple and effective module for preventing home flooding in the kitchen or bathroom. It is placed on the floor in places of potential danger. The operating principle is based on water closing the contacts, which leads to a signal being sent to the smart home's control panel. An automatic valve with an electromagnetic valve, which shuts off the central water supply, is installed for quick response in the absence of the user.
2.10 Air Quality Sensor
Such devices most often allow for comprehensive monitoring of humidity, temperature, and carbon monoxide presence, but the main purpose is to determine the number of harmful micro-particles PM2.5 for the organism. These include various organic compounds—formaldehyde, acetone, chloroform, cyanide, phenol, benzene, and many others. In case of excess norms, the air quality analyzer sends a signal that can activate cleaning systems or ventilation equipment.
3. Autonomy and Centralized Control Capabilities
To create a smart home, manufacturers develop sensors with different sets of functions. Some are focused on synchronization with a central hub, while others are autonomous. The first ones are suitable for professional systems, while independent ones are more geared toward amateur home control and always wireless. Let's consider the features of each type with the help of a table.
| Type of Control | Advantages | Disadvantages |
|---|---|---|
| Centralized |
|
|
| Autonomous |
|
|
It is worth noting that autonomous systems are more popular at home due to wireless technologies and a wide range of equipment for various tasks. They connect to cloud services via Wi-Fi, are easily configured and controlled through an intuitive interface from anywhere globally. However, such sensor functionality is limited to monitoring indicators and notifying of dangerous situations. In case of threats, security mechanisms are not provided. Similar devices include smart sockets, smart bulbs and other equipment with intelligent control.
4. Sensor Synchronization Methods with the Hub
Sensor integration into a smart home system is done in two ways—wired and wireless. In this case, it all depends on the configuration, service area, and overall concept. Professional complexes are usually designed for wired connection. They include a full range of sensors and a physical hub that receives signals and provides the appropriate response. Most of the time, all equipment is supplied as a set from one manufacturer, ensuring complete compatibility. This approach allows covering a large area of commercial and industrial objects, spacious multi-story cottages with adjacent buildings (garage, wine cellar, shelter, sauna, gazebo). However, installing a wired smart home is very costly and requires careful planning even before construction or renovation of the apartment.
Creating a wireless smart home can be implemented at any time, but the area is limited by network connectivity capabilities. The most common communication standards are:
- ZigBee — the most popular network protocol specifically developed for monitoring and smart home systems. It is characterized by universal compatibility and interaction of all components via MESH technology, minimal energy consumption, which is significant for wireless battery-powered devices. Signal transmission to the central hub can be done indirectly through other sensors, expanding the service area.
- Z-Wave — also quite a widespread standard for remote signal transmission without wires. It operates at frequencies with minimal interference, guarantees high retransmission speed, and features reduced energy consumption.
- Bluetooth — typically used for local direct connection to the sensor using mobile gadgets. The range is about 20 meters.
- Wi-Fi — a universal method for management, configuration, and monitoring. It can be used both for direct sensor synchronization with the hub and connection through a home wireless network involving a router. With the appropriate software and internet, remote management from anywhere globally is possible.
- Jeweller — a relatively new wireless communication protocol developed by the Ukrainian company Ajax Systems for its security systems. A complex installation of proprietary equipment guarantees rapid signal transmission over long distances (more than 1 km) with high protection through encryption. Moreover, the controller can recognize sensor hacking, signal interception, jamming, and take appropriate security measures.
- Thread — a modern evolving standard that encompasses the best from the above-listed ones. Its main feature is scalability and fault tolerance. Unlike other methods, it can contain several hubs within its structure, each servicing up to 500 sensors. The system effectively distributes the load, requires minimal energy, and continues to operate when one of the hubs fails.
A digital touch-panel is usually installed for management, creating a direct link and stable access to all connected actuating devices and sensors. Considering the trend towards wireless technology development, manufacturers often provide proprietary software for remote control via smartphone or tablet.
5. Importance of Proper Configuration
For a smart home to bring joy and truly provide comfort, it is necessary to configure the sensors correctly. Smoke, gas, and vibration analyzers need precise sensitivity calibration so that the alarm doesn't disturb tranquility during cooking or hammering. Motion sensors require a similar approach, and an "Animal Immunity" function becomes useful if pets are present. It is also crucial to choose the installation location correctly and minimize the risk of physical damage by intruders. Security motion modules are best mounted in open areas to exclude foreign objects that provoke activation from entering the active zone.