Ajax Systems has quietly become one of the most respected names in the UK professional security market. Where consumer systems like Ring trade on simplicity and smart home integration, Ajax is built to a different brief: encrypted two-way radio, four independent internet channels, and genuine compatibility with professional Central Monitoring Stations. The Hub 2 Plus is the top residential and light-commercial hub in the range, and paired with the Jeweller-protocol MotionProtect and DoorProtect sensors, it forms a system that can be owner-installed yet monitored to professional standards.
What Is the Ajax Alarm System?
Ajax Systems is a Ukrainian security electronics manufacturer founded in 2011. Its Jeweller wireless protocol underpins every sensor in the range, using encrypted two-way radio communication with dynamic key authentication to resist spoofing and jamming. The system runs on a custom real-time operating system called Malevich — designed to be resistant to viruses and cyberattacks — and receives over-the-air firmware updates several times a year. In the UK, Ajax hardware is stocked by professional security distributors and available on Amazon, and the company maintains a growing network of certified installers.
Hub 2 Plus: Specs and Connectivity
Four communication channels. The Hub 2 Plus connects to the internet via Ethernet, Wi-Fi, and two SIM card slots supporting 4G LTE, 3G, and 2G. Each channel is independent: if your broadband goes down, the hub switches seamlessly to a SIM; if one SIM network has an outage, the second takes over. For home security, this level of redundancy is rarely found outside professionally installed systems.
Capacity and range. The hub supports up to 200 connected devices and 25 security groups, serving everything from a single-room flat to a multi-zone commercial premises. Ajax's Jeweller radio achieves up to 2,000 metres of open-space range between hub and sensor — far beyond the Wi-Fi-dependent range of most consumer alarms. With five range extenders, coverage can extend across up to 35 km².
Backup power. A built-in 3 Ah lithium-ion battery provides up to approximately 15 hours of operation if mains power is cut — a key requirement for a system designed to deter determined intruders.
Photo verification. The Hub 2 Plus supports up to 200 MotionCam devices, which capture photos on alarm trigger for visual verification by a monitoring station. This can significantly reduce false-alarm charges from response services.
UK pricing for the Hub 2 Plus typically starts at around £200–£250 for basic variants; models with full 4G LTE and dual SIM are listed on Amazon.co.uk in the £380–£490 range depending on colour and configuration. Prices vary by retailer and fluctuate frequently.
MotionProtect Sensor
Wireless PIR with pet immunity. The MotionProtect is Ajax's standard passive infrared motion detector. Built around an Excelitas Technologies PIR sensor with a Fresnel lens and SmartDetect algorithm, it analyses thermal patterns, movement speed, and signal intensity to distinguish humans from animals. It will filter out pets up to 20 kg and 50 cm in height, reducing false alarms without sacrificing sensitivity to intruders.
Detection range reaches up to 12 metres, with an 88.5° horizontal field of view. Ajax recommends mounting it at 2.4–2.5 metres high on a wall or corner. A pre-installed CR123A battery is rated for up to five years of autonomous operation, and the hub reports low-battery warnings months in advance.
The sensor communicates with the hub at ranges up to 1,700 metres in open space. Like all Jeweller devices, it includes a tamper switch that triggers an alert if the casing is removed. UK street pricing is around £30–£50 per unit.
DoorProtect Sensor
Reed-switch opening detector. The DoorProtect monitors doors, windows, and skylights using a magnetic reed switch. It ships with two magnets — one suited to gaps up to 1 cm, a second for larger frames up to 2 cm — allowing installation on the vast majority of UK window and door profiles without drilling or cable runs.
The reed switch is rated for over two million openings, and the CR123A battery is specified for up to seven years of use. Communication range in open space is quoted at up to approximately 1,200 metres. Like the MotionProtect, the DoorProtect includes a tamper alarm and block encryption with dynamic keys. An optional pair of terminals on the body allows connection of a third-party hardwired NC contact — useful for installing alongside existing magnetic contacts during a system upgrade.
Ajax App Experience
Ajax provides native apps for iOS and Android, plus desktop clients for Windows and macOS. Setup involves scanning a QR code on each device with the hub's app to pair it — no tool access to the hub enclosure required, as sensors mount on SmartBracket plates that clip on and off independently. Once live, the app shows real-time status for every device, battery levels, signal strength, and event history. You can arm and disarm remotely, create automation scenarios (up to 64 on the Hub 2 Plus), and manage multiple users with granular permissions.
The interface is clean and logically organised. Notifications arrive quickly — Ajax quotes connection loss detection within 60 seconds and device polling every 12 seconds — though the system is designed primarily around security events rather than smart home integration. Ajax does not natively integrate with Google Home, Amazon Alexa, or Apple HomeKit.
Professional Monitoring: Central Station Feature
One of Ajax's clearest differentiators from consumer systems is its built-in support for connecting directly to a Central Monitoring Station (CMS). The hub can be configured to transmit alarm events directly to a security company's CMS software — bypassing the Ajax cloud — using protocols supported by major platforms including Manitou, Patriot, SoftGuard, and others via the Ajax Translator PRO integration.
This means a UK homeowner can choose to have their Ajax system monitored by a professional alarm receiving centre (ARC), with police or keyholder response, entirely through the standard app setup flow. Professional monitoring contracts are arranged with third-party UK security companies rather than through Ajax directly, but the infrastructure is ready out of the box. For a thorough look at a consumer system with its own built-in monitoring subscription, see our Ring Alarm UK review.
UK Installer Network and Availability
Ajax has invested heavily in the UK professional installer market. The company operates a partner programme with training and certification routes, and certified installers are listed through Ajax's own partner search. Professional installation of a standard home system typically takes three to four hours, including configuration and user training. For those who prefer a hands-on approach, the system is fully self-installable — the QR-code pairing and app-guided setup are genuinely accessible to a confident DIYer.
Hardware is available through UK security distributors, selected electrical wholesalers, and directly via Amazon.co.uk. If you are evaluating other access control options alongside a new alarm, our guide to the best smart locks in the UK covers compatible deadbolt and mortice options worth pairing with a new security system.
Ajax Hub 2 Plus vs Ring Alarm
Ring Alarm is the most popular DIY alarm system in the UK, and it starts at roughly £100 for a basic kit — well below the Ajax Hub 2 Plus entry price. Ring's strength is tight integration with Amazon Alexa and Ring Video Doorbells, plus a simple £10-per-month monitoring subscription. But it depends entirely on Wi-Fi; if your broadband is cut, you lose connectivity.
Ajax answers that with four communication channels, professional CMS compatibility, significantly greater sensor range (up to 2,000 m vs Wi-Fi-limited coverage), and a system that scales to commercial sites. Ring is the right choice if you want a low-cost, Alexa-integrated system with a no-commitment monthly plan. Ajax is the right choice if you want genuine redundancy, professional-grade encryption, and the option to connect to a monitored response service.
UK Pricing Summary
Prices vary between retailers and change regularly. As a guide, the Hub 2 Plus with dual SIM and Wi-Fi is listed on Amazon.co.uk at approximately £380–£490 depending on configuration; basic 2G variants start lower. Individual MotionProtect sensors are priced at around £30–£50 each, and DoorProtect sensors in a similar bracket. A starter kit covering a typical two-bed flat — one hub, two MotionProtect sensors, and four DoorProtect sensors — would typically come to around £600–£700 before any professional installation fee. Always check Amazon.co.uk and authorised UK distributors for current prices.
Verdict
The Ajax alarm system earns its premium price by delivering four-channel redundancy, genuine professional monitoring compatibility, and a sensor network that outranges consumer Wi-Fi alternatives by an order of magnitude. The Hub 2 Plus is not the cheapest starting point in UK home security, but for anyone who wants a system that behaves like a professionally installed alarm — with the flexibility to self-install and manage it from an app — it is difficult to beat. If budget is the primary concern, Ring Alarm remains a capable alternative; if security is the priority, Ajax is the stronger system.
Related: best home security systems UK, ADT smart home review, and smart home security tips UK.
