The Ajax DoorProtect U Jeweller White is a professional wireless magnetic opening detector designed to protect doors, windows and other entry points. Featuring secure Jeweller wireless communication, support for an external wired detector and up to 7 years of battery life, it provides dependable perimeter protection for compatible Ajax security systems.
Ajax DoorProtect U Jeweller White Wireless Reed-Switch Opening Detector
The Ajax DoorProtect U Jeweller White is a compact wireless magnetic opening detector designed to detect the opening of doors, windows, skylights and other protected access points. Designed for use with compatible Ajax security systems, it provides reliable perimeter protection while maintaining simple installation and long-term battery operation.
Using Ajax's secure Jeweller radio protocol, the detector communicates alarm events quickly and reliably to the hub, helping protect residential and commercial properties against unauthorised entry.
Reliable Perimeter Protection
DoorProtect U detects when a protected door or window is opened using a magnetic reed switch.
Once the magnetic field changes as the door or window opens, the detector immediately sends an alarm signal to the connected Ajax hub, allowing users or monitoring centres to respond quickly.
Its compact design makes it suitable for discreet installation on a wide variety of doors and window frames.
Jeweller Wireless Communication
The detector communicates using Ajax's proprietary Jeweller wireless technology, providing dependable encrypted communication between the detector and the hub.
Confirmed benefits include:
- Encrypted two-way communication
- Device authentication
- Frequency hopping
- Anti-jamming protection
- Automatic supervision
- Wireless communication range of up to 1,200 metres in open space
Actual communication distance will depend on the installation environment and building construction.
Support for External Wired Detectors
Unlike a basic magnetic contact, the DoorProtect U includes an input for connecting a compatible normally closed (NC) wired detector.
This allows installers to integrate an additional wired detection device while continuing to manage alarms through the Ajax system, providing greater installation flexibility where required.
Long Battery Life
The detector is powered by a pre-installed CR123A lithium battery, providing up to 7 years of operation under normal conditions.
Its low power consumption helps minimise maintenance while ensuring reliable everyday performance.
Quick Installation
The detector is designed for straightforward installation using the supplied mounting accessories and pairing process within the Ajax application.
A built-in tamper switch helps notify users if the detector is removed from its mounting surface.
Designed for Everyday Security
Whether protecting a front door, rear entrance, office access point or ground-floor window, the DoorProtect U provides dependable opening detection for a wide range of residential and commercial security applications.
Its compact size and wireless operation make it particularly suitable for installations where running cables would be impractical.
Key Benefits
- Dual reed switches provide accurate detection regardless of magnet placement
- Anti-chatter technology helps reduce false alarms from vibration
- Refined to meet strict UK regulatory standards
- Terminals allow integration of a third-party wired NC detector
- Chime function can turn the detector into a doorbell with a compatible Ajax siren or keypad
- Up to 7 years of battery life reduces ongoing maintenance
- Low battery notifications sent months in advance of replacement
- Encrypted Jeweller communication helps protect against sabotage, spoofing and jamming
- Communication loss can be detected and reported within 36 seconds
- Sabotage and tamper protection adds an extra layer of security
- Ready to use out of the box with a pre-installed battery
- Quick installation via SmartBracket mounting panel
Key Features
- Wireless reed-switch opening detector (dual reed switch)
- Anti-chatter technology
- Two magnet options (1 cm / 2 cm activation threshold)
- Terminals for third-party NC detector
- Chime doorbell function (requires Ajax siren or keypad with buzzer)
- Jeweller wireless technology
- Up to 1,200 m communication range
- Battery life up to 7 years
- Low battery notifications
- Sabotage/tamper protection
- SmartBracket mounting panel
- UK regulatory compliant (U variant)
- Indoor installation
- White finish
Ideal For
- Homes and apartments
- Offices
- Retail shops and commercial premises
- Industrial premises
- Doors, windows, skylights and safes
- Multi-floor buildings
- Ajax security systems
System Compatibility
- Compatible with Ajax Hub
- Compatible with Ajax Hub Plus
- Compatible with Ajax Hub 2 (2G)
- Compatible with Ajax Hub 2 (4G)
- Compatible with Ajax Hub 2 Plus
- Compatible with Ajax Hub Hybrid (2G)
- Compatible with Ajax Hub Hybrid (4G)
- Compatible with Ajax ReX and ReX 2 range extenders
- Uses Ajax Jeweller encrypted wireless communication
- Managed via Ajax mobile applications (iOS and Android)
- Managed via Ajax desktop applications (Windows and macOS)
- Supports Ajax Cloud remote management
- Supports connection to compatible Central Monitoring Stations (CMS)
- Can be combined with devices from other Ajax categories (video surveillance, fire and life safety, comfort and automation) in the same system
Technical Specifications
| Specification |
Details |
| Brand |
Ajax |
| Model |
DoorProtect U Jeweller |
| Part Number |
121293.03.WH1 |
| Product Type |
Wireless Magnetic Door & Window Opening Detector |
| Detection Method |
Reed Switch Magnetic Contact |
| Protected Openings |
Doors, Windows, Skylights and Similar Opening Elements |
| Wireless Technology |
Jeweller |
| Radio Communication Range |
Up to 1,200 m (Open Space) |
| Radio Frequency Bands |
868.0–868.6 MHz (Region Dependent) |
| Alarm Transmission Time |
Approximately 0.15 Seconds |
| External Detector Input |
Yes (Normally Closed Wired Detector) |
| Magnet Options |
Small and Large Magnet Supported |
| Tamper Protection |
Yes |
| LED Indication |
Yes |
| Power Supply |
1 × CR123A Lithium Battery (Pre-installed) |
| Battery Life |
Up to 7 Years |
| Protection Rating |
IP20 |
| Operating Temperature |
−10°C to +40°C |
| Operating Humidity |
Up to 75% Non-condensing |
| Colour |
White |
| Material |
High-quality Plastic |
| Mounting |
Surface Mount |
| Dimensions |
90.5 × 21 × 18.5 mm |
| Weight |
Approximately 54 g |
| Indoor / Outdoor |
Indoor Use Only |
| Certifications |
CE, RED, RoHS (Region Dependent) |
| Warranty |
Not specified |
Frequently Asked Questions (FAQs)
What is the Ajax DoorProtect U Jeweller used for?
It is a wireless reed-switch opening detector that notifies of intrusion when a protected door, window, skylight or safe is opened, suitable for residential, commercial and industrial Ajax security systems.
What does "U" mean in the product name?
The "U" indicates this detector has been refined to meet strict UK regulatory requirements. It is the correct version for UK security installations, sold under article number 121293.03.WH1.
Is this detector suitable for outdoor installation?
No. The DoorProtect U Jeweller is designed for indoor use only. Outdoor installation can cause false alarms or device failure.
Can a third-party detector be connected?
Yes. The unit includes a connector for one third-party wired NC detector, allowing existing or additional wired opening, motion or vibration detectors to be integrated into the same Ajax system. It cannot power that detector — a separate power source is required.
What is the Chime feature?
When paired with a compatible Ajax siren or a keypad with a built-in buzzer, the detector can play one of four short beep patterns whenever an opening is detected while the system is disarmed — useful as a shopkeeper's bell for retail entrances.
How long does the battery last?
The pre-installed battery is rated for up to 7 years of autonomous operation under typical conditions, with low-battery notifications sent months in advance.
What is the maximum wireless range?
Up to 1,200 metres in open space between the detector and the hub or a compatible range extender.
Does it support shock or tilt detection?
No. This standard model provides opening detection only. For shock and tilt detection, see the DoorProtect Plus U Jeweller range.
How quickly is a communication loss detected?
With minimal polling interval settings, communication loss can typically be detected and reported within approximately 36 seconds.
Does it include tamper protection?
Yes. The detector includes sabotage and tamper protection, immediately notifying the system if it is detached from its mounting surface.
