
MotionProtect Plus U Jeweller
Wireless PIR motion detector with an additional K-band microwave sensor
Product is not available in your region
Precise motion detection in a complex environment
MotionProtect Plus U Jeweller is a wireless motion detector equipped with an additional microwave sensor for enhanced accuracy. It detects the movement of objects with temperatures similar to those of the human body. When motion is detected, the device performs an RF scan of the area using its built-in K-band microwave sensor. This approach helps prevent false alarms caused by thermal radiation emitted by objects, such as air conditioners or fireplaces.
In an Ajax system, you can combine devices of all product categories: Intrusion protection (both Superior and Baseline), Video surveillance, Fire and life safety, or Comfort and automation. Create the system to suit your needs and manage it in a single interface.
Wherever there is a risk of intrusion
Discover future-proof hardware

Fresnel lens

Pre-installed battery

PIR sensor

K-band microwave sensor

Tamper button

Jeweller antenna

SmartBracket mounting panel

Holding screw for a more reliable fastening
No intruder goes unnoticed
PIR sensor
All Ajax motion detectors use PIR sensors by Excelitas Technologies, a field-leading American manufacturer specializing in designing and producing optronic components since 1931. Ajax Systems constantly proves the sensor’s superior quality at the production stage: we test 100% of the manufactured devices. This approach ensures the utmost accuracy of intrusion detection.

K-band microwave sensor
The K-band microwave sensor scans a room to minimize false alarms caused by thermal radiation. Operating in conjunction with the PIR sensor, it uses microwave technology only for PIR sensor alarm verification. Unlike traditional X-band sensors, the K-band sensor offers enhanced precision and superior energy efficiency. This results in minimal impact on battery lifespan and significantly fewer false alarms. Additionally, the sensor is completely safe and does not harm human health.

K-band

X-band
Special lens
The pattern of the Fresnel lens sections is designed to differentiate between the IR diagrams of people, animals, and objects that can cause false alarms. Large lens sections capture radiation at the level of an adult’s head and torso, while the smaller sections make the diagram more detailed. The lens provides the detector with accurate data on thermal objects in the detection zone and the nature of their motion.

Thermal interference filter

We processed thousands of thermal patterns caused by people, pets, and the environment to develop the SmartDetect software algorithm. In armed mode, the detector constantly analyses the thermal diagram from the PIR sensor, including the IR radiation intensity, thermal spot size, movement speed, time spent in the detection zone, and other parameters. The algorithm filters out false alarm triggers instantly and with high accuracy. As a result, the detector accurately responds to human motion without false alarms.


False alarm
Real alarm


False alarm
Real alarm


False alarm
Real alarm
Temperature compensation
Temperature compensation is a software mechanism that maintains the contrast of the thermal diagram even if the ambient temperature is close to the temperature of the human body. With each ambient temperature measurement, the detector adjusts the PIR sensor data according to the coefficient table stored in its memory. The detector is effective over the entire operating temperature range.

Sensitivity level
The detector features four sensitivity levels that can be adjusted in an Ajax app. PRO users can choose from three sensitivity levels to balance detection accuracy with false alarm prevention. Low sensitivity makes the detector less likely to respond to an active pet. With high sensitivity, an alarm is raised whenever there is any movement in the detection area. The optimal setting can be determined during installation via the detection zone test. The setting can be adjusted at any time when the system is disarmed if environmental conditions change or false alarms occur.

Professional installation
When installed properly at a height of 2.4 m and with the lens facing directly toward a potential intrusion path, the detector provides an accurate thermal diagram and is immune to pets. It instantly responds to real threats, minimizing false alarms caused by pets that weigh up to 20 kg and are under 50 cm in height.

Stable and reliable performance
MotionProtect Plus U Jeweller is equipped with a high-quality battery from proven manufacturers only. In addition to real-time testing during battery production, Ajax Systems inspects every unit to ensure the accuracy of the batteries’ characteristics. The battery provides stable performance at temperatures from –10 °C to +40 °С.
Early low battery notifications
High quality proven by regular tests
Up to 5 years of autonomous operation


Jeweller
Unique wireless technology
Jeweller is Ajax’s proprietary radio protocol for secure two-way communication. It provides block encryption and device authentication during each communication session with an Ajax hub or radio signal range extender. Jeweller prevents sabotage, spoofing, and data theft.
Up to 1,700 m of communication range in an open space
Data encryption
Notification of jamming and connection loss
Automatic power adjustment
Communication through steel and concrete
Some facilities have thick walls, metal partitions, or sheer distances that affect signal quality. Ajax range extenders are designed to increase the range of a wireless network and deliver stable connection with a hub despite the obstacles. And by choosing the model with an Ethernet cable connector, you get an additional communication channel. А single system can accommodate up to five range extenders.
Up to 5 range extenders within one system
Ethernet-equipped model available




System supervision
The device performs automatic self-diagnosis and reports its state to the hub. Essential parameters, including tamper, communication, power supply, and sensor states, are continuously monitored. The Ajax Cloud server controls communication between the hub and Ajax apps, ensuring instant notifications for ARCs and users. In case of any malfunction or communication failure, an engineer is informed immediately to provide necessary services.
Automatic device self-diagnosis with a state report
Regular polling to display the current device state in Ajax apps
Instant maintenance notifications

Sabotage resistance






Effortless installation and setup
MotionProtect Plus U Jeweller is ready to operate straight out of the box. Using the SmartBracket panel, an installer can effortlessly mount the device, eliminating the need to disassemble the enclosure. Ajax apps help quickly make the device part of the ecosystem: simply scan the QR code to add the device to the hub. All settings can be configured remotely. Therefore, on-site visits are not needed.
Pairing with the hub via the QR code

Easy installation with the SmartBracket mounting panel

Configuring and testing in Ajax mobile and desktop apps

The Ajax PRO Desktop app for macOS and Windows

In an open space.
Technical information
MotionProtect Plus U Jeweller
More Ajax motion detectors
Ajax product categories
In an Ajax system, you can combine devices of all product categories: Intrusion protection (both Superior and Baseline), Video surveillance, Fire and life safety, or Comfort and automation. Create the system to suit your needs and manage it in a single interface.