Intelligent radio signal range extender


To increase the radio communication range of your KeyPad Combi, use the ReX radio signal range extender.


Yes, DualCurtain Outdoor works with ReX range extenders.


With OS Malevich 2.9 update, temporary deactivation of devices without removing them from the system has become available. Deactivation may be necessary if the device is incorrectly installed or configured, loses connection with hub, or is defective.

To deactivate a device, go to its settings (Ajax appDevices tab → select the device you needSettings Temporary Deactivation).


Divide the capacity of the external battery by the power consumption of the central panel.

Power consumption of the central panel depends mostly on active communication modules — the average values ​​are indicated in the table:

Central panel Active communication modules Average input current
Hub GSM 42 mA
Ethernet 80 mA
GSM+Ethernet 90 mA
Hub Plus GSM 35 mA
Ethernet 72 mA
GSM+Ethernet 93 mA
Wi-Fi 20 mA
Wi-Fi+GSM 42 mA
Wi-Fi+Ethernet 80 mA
Wi-Fi+GSM+Ethernet 96 mA
Hub 2 GSM 33 mA
Ethernet 80 mA
GSM+Ethernet 86 mA
Hub 2 Plus GSM 146 mA
Ethernet 200 mA
GSM+Ethernet 248 mA
Wi-Fi 98 mA
Wi-Fi+GSM 147 mA
Wi-Fi+Ethernet 213 mA
Wi-Fi+GSM+Ethernet 285 mA
ReX 20 mA

For instance, when connected to a 40A·h battery, Hub 2 — with active GSM module only — will operate approximately 1200 hours (40A·h / 0.033A).


Replace the standard 110/230 V power supply unit with 12V PSU for Hub/Hub Plus/ReX.


The list of ReX compatible devices:

Security detectors
Fire detectors
Leakage detectors
Automation devices
Control devices
Integration modules

ReX is not compatible with ocBridge Plus, uartBridge and MotionCam.


In order to assign device to hub:

  1. Go to ReX Settings in the Ajax application (Devices ReX Settings ).
  2. Click Pair with device.
  3. Uncheck the devices that should directly operate via the hub.
  4. Click Back to save the settings.

In order to assign device to ReX:

  1. Go to ReX Settings in the Ajax application (Devices ReX Settings ).
  2. Click Pair with device.
  3. Select the devices that should operate via the range extender.
  4. Click Back to save the settings.

The devices operating via the range extender are labeled with RE icons in the application’s list of hub devices. In addition, the latter is also specified in the device menu, in the Operates via ReX field.

Ajax mobil applications

ReX is designed to operate on a power supply of 110V–240V AC, 50/60 Hz. In the event of a power failure, ReX is fitted with a backup battery that ensures up to 35 hours of operation of the range extender.

Also ReX can be connected to 12 volt DC sources.


The number of ReX range extenders connected to the Ajax security system depends on the hub model:

Hub 1
Hub Plus 5
Hub 2 5
Hub 2 Plus 5

Only hubs on OS Malevich 2.8 and higher support the connection of several ReX.


Alarms are communicated within 0.3 seconds.


In the event of a loss of connection between the hub and ReX, all devices connected to the range extender also lose connection with the hub.

By copying the system information from the hub, ReX creates an autonomous group of devices and responds to events instantaneously. If ReX continues to communicate with the connected devices when the connection with the hub is lost, ReX assumes the role of the control panel: it will receive an alarm signal from the detector and activate the siren.

Users can manage the security modes of ReX and of the devices connected to the range extender only after the connection between the range extender and the hub is restored.


ReX functions at a distance of up to 1,800 meters from the hub and can double the radio communication range between the Ajax devices and the hub.

rex range extender

The communication range between ReX and a paired device is limited by the radio signal range of the device (the relevant parameter is indicated in the device’s specifications on the website and in the User Manual).

You can significantly expand the coverage area of the Ajax radio network using several ReX in the security system. However, keep in mind that ReX can only be connected directly to the hub and connecting one range extender to another is not supported.

The number of ReX connected to the security system depends on the hub model.


No. ReX expands the security system’s radio communication coverage, thereby enabling the installation of Ajax devices at greater distances from the hub or in locations where a reliable signal reception from the control panel cannot be ensured.

rex range extender

ReX expands the hub’s radio communication coverage.


ReX receives hub signals and transmits them to the devices connected to the range extender. It also transmits signals received from the devices to the hub. Two-sided connection is provided by the Cargo protocol operating over the Jeweller radio protocol.

rex range extender

Unlike regular range extenders that only re-broadcast signals, ReX controls the functioning of the security system devices. By copying the system information from the hub, ReX creates an autonomous group of devices and responds to events instantaneously. If the hub disconnects from the network for whatever reason, ReX receives an alarm signal from the detector and activates the siren.

ReX does not increase the number of devices connected to the hub!



Tamper is a miniature button on the device board. It is released when the lid is opened as well as a result of an attempt to unfasten and/or lift the device from the surface, which initiates an event.

When the tamper is released, the Hub sends push notifications and SMS messages (if this type of notification is enabled) to all users of the security system and also communicates the event to the central monitoring station of the security company.

If the tamper is released, Ajax applications display the Open status in the Lid field of the device menu. In addition, a malfunction badge appears on the device icon.



By default, the hub is set to a hub–detector ping interval of 36 seconds and 30 undeliverable data packets to consider the device lost. With these settings, the hub will detect the loss of the detector in 18 minutes.

To reduce this time, go to the hub settings in the Jeweller section and change the settings. The minimum time for detecting loss of connection with the device is 36 seconds (3 polls of 12 seconds each).

The time before raising the alarm by the communication loss between hub and device is calculated with the following formula:

Ping interval * (number of undelivered packets + 1 correction packet).

Note that with the minimum ping interval, short-term interference can lead to loss of connection with the device. Therefore, set the minimum values only if it is critically important to promptly inform about events in the system.


The loop (zone) number is required to add a guarded facility to the CMS along with descriptions of all devices connected to the hub.

The loop (zone) number is available in the settings after activating the group mode in the Ajax application:

  1. Hub Settings Groups

Having selected a group, you will see a list of its devices. Each device has a Device No. (or DeviceIndex in Ajax PRO Desktop) that corresponds to the loop (zone) number. A number is assigned when a device is attached to the Hub. The first added device has the first loop (zone) number.

After a device or a detector is removed, its number will be assigned to the next added device. However, the numbering of other devices will not change.


In the Ajax app, select the «Devices» tab . Information about the firmware version and device ID is located at the very bottom of the tab with the device parameters.

Ajax mobil applications

Go to the Device tab , select the device you want to check.

ajax security system application

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