Ajax Hub (4G) Jeweller: What It Does and How to Run It

The Ajax Hub (4G) Jeweller is the control panel of an Ajax intruder alarm system: the box that talks to every sensor, decides what counts as an alarm, and passes it on to your phone and, if you have one, to a monitoring centre. It is made by Ajax Systems and is the 4G version of the Hub (2G) Jeweller, so it can use a mobile network as well as a wired internet connection¹.

If you are choosing one, the numbers that decide it are these. It takes up to 100 Ajax devices, with a radio range of up to 2,000 m in open space, and it holds up to 50 access codes¹. Its built-in backup battery keeps the system running for up to 15 hours when the Ethernet connection is switched off¹. It reaches the Ajax Cloud over Ethernet and a SIM card, and if one channel drops it switches to the other and tells the monitoring centre and users¹.

If you already own one, the routine is simple: fit it indoors, away from the router and power cables, keep the SIM funded, check it once every three months, and clean it only with a mild method the maker allows¹. This page sets out what it does, what it can and cannot do, and how to run it safely.

What the Hub (4G) Jeweller does

The hub is the control panel of the Ajax system¹. Every detector, keypad, siren and range extender in the system reports to it, and it holds both user and system settings as well as the parameters of the connected devices¹. It is intended for indoor installation only¹.

It is a Jeweller system, which means the devices talk to the hub over Ajax's own radio protocol rather than over your home wi-fi. Jeweller uses polling to show real-time device status and to carry alarms, events and readings into the Ajax apps². The hub does not support every Ajax device, so the maker directs buyers to the Ajax devices compatibility table before adding hardware¹.

The 4G model differs from the 2G version in several ways that matter to a household:

• It supports 4G (LTE) networks, where the 2G version supports only 2G networks¹.
• It supports scheduled access, letting you set temporary access to the premises on specific days and at specific times¹.
• It supports setting templates, which apply preconfigured settings to a group of devices at once¹.
• It supports a system integrity check in the Ajax PRO apps, which the 2G model does not¹.
• It displays its IMEI, the 15-digit serial number that identifies the hub's modem on a mobile network, and only when a SIM card is fitted¹.

The box contains the hub, the SmartBracket mounting panel, a power supply cable, an Ethernet cable, an installation kit, a GSM start package or Ajax SIM (not available in all countries) and a quick start guide¹.

Specifications: up to 100 devices and 2,000 m radio range

The headline capacity is up to 100 Ajax devices on one hub, protecting against intrusion, fire and flooding¹. The radio range is up to 2,000 m in open space, for example without walls, doors or inter-floor construction¹. In a real house, walls and floors cut that down, which is why Ajax sells a range extender: the hub accepts one range extender alongside up to 10 sirens or keypads with a built-in buzzer¹.

How many devices you can actually run depends on how often the hub checks in with them. The device ping interval is 36 seconds by default, and the maker gives these limits¹:

The hub counts missed pings to decide a device has failed to report, with 8 packets by default¹. A shorter interval means faster fault detection but fewer devices; the default of 36 seconds allows the full 100¹.

Other limits worth knowing before you plan a system:

• Tag and Pass: the Hub (4G) Jeweller supports 50 Tag and Pass devices³.
• Keypads and sirens: running OS Malevich 2.33 and later, the hub supports up to 10 sirens and up to 50 keypads with a built-in buzzer¹.
• Access codes: up to 50¹.
• Offline events: the buffer holds between 100 (the default) and 1,000 events, in steps of 50¹.
• Video: for hubs running OS Malevich 2.42.111 or later, the maker provides a video device calculator to work out how many third-party video devices the hub can take¹.

The hub does not support scenarios based on temperature, humidity, CO2 concentration, or touching the LightSwitch Jeweller¹. If you want those automations, they are not available on this panel.

Backup battery: up to 15 hours if the power goes off

The hub has a built-in rechargeable backup battery that keeps the system running when mains power fails⁴. The maker's figure for this model is up to 15 hours of autonomous operation when the Ethernet connection is switched off¹. Ajax's own support material also gives a general figure of up to 14 hours of autonomous system operation for the built-in battery across its hubs⁵. The two figures come from different Ajax documents and differ by an hour; treat 14 to 15 hours as the working range and do not rely on the longer end.

The battery also powers Fibra devices during a power outage, including wired devices whose optional external power supply is unavailable⁴. The charge level shows in the app in 5% increments¹.

For context, an alarm system's backup battery is normally expected to last at least 12 hours in a power cut, according to independent guidance from the NSI⁶. Ofcom's rules for telephone backup units are a different case: providers must offer at least one hour of backup in a power cut, and some provide up to seven hours⁷. The hub's 14 to 15 hours sits comfortably above both, but it is not indefinite.

Two settings change how the battery is used. The hub stays connected to the Ajax Cloud for 10 minutes after any system event by default, adjustable from 5 minutes to 1 hour, which affects how hard the radio and modem work after an alarm⁸. And in a power cut the hub's indicator does not start flashing immediately: it waits 180 seconds¹.

Two ways to reach the cloud: Ethernet and a 4G SIM

The hub's available communication channels are Ethernet and a SIM card¹. The Ajax Cloud service can communicate with a hub over several independent channels, including Ethernet, wi-fi and cellular⁹. If one channel becomes unavailable, the hub automatically switches to another and notifies the security company's monitoring centre and system users¹. That is the point of paying for the 4G model: a cut phone line or a failed router does not silence the system.

For the SIM, the maker specifies a micro SIM card with the PIN code request disabled, which you can do from a mobile phone, and enough funds on the account to pay for GPRS and SMS services¹. Ajax SIM cards need OS Malevich 2.16 or later to activate¹. If the hub has enough funds or bonus SMS it can send text messages even when the app shows the cellular data status as not connected¹.

Signal strength decides whether the mobile side is worth having. The maker recommends installing the hub where signal strength is 2 to 3 bars; at 0 or 1 bar the hub cannot send an SMS about an event or alarm¹. The hub needs approximately 2 minutes to identify the available communication channels after switch-on¹.

If the Ethernet connection does not come up by itself, the maker's instruction is to disable proxy and MAC address filtering and enable DHCP in the router settings, so the hub receives an IP address¹. If the connection between hub and cloud is lost, Ajax recommends checking the hub's internet connection first⁹.

What the LED colours mean

The Ajax logo on the front of the hub lights red, white, purple, yellow, blue or green depending on the system's state¹. The colours a household will see most often are these:

A steady red logo is the one to act on. It means the hub has lost its route to the internet or to Ajax Cloud, so alarms may not reach your phone or the monitoring centre. Ajax's own troubleshooting note says that when hub communication with the server fails, the Ajax logo lights red¹². The hub notifies users and the security company within 60 seconds of losing the connection by default¹, and the app can alert you with a standard push notification or with a siren sound, which is enabled by default¹. The delay before a server failure alarm is raised can be set from 30 to 600 seconds, with a recommended default of 300 seconds, and the hub polls the server every 10 to 300 seconds, recommended 60¹.

The logo's brightness is adjustable from 1 to 10, with 10 as the default¹. If the panel sits in a bedroom, turning it down is a setting, not a fault.

Maintenance, warranty and support

The maker's recommended routine is a check once every three months¹. That is the moment to confirm the logo colour, look at the battery level in the app, check the SIM has credit, and test that alerts still reach your phone.

Cleaning is deliberately limited. The maker says not to use any substances containing alcohol, acetone, petrol or other active solvents on the hub¹. A dry or lightly damp cloth is the safe approach; anything harsher risks the casing and the logo.

When fitting or refitting the hub:

• Do not place it close to radio interference sources, meaning less than 1 metre from the router and power cables¹.
• Do not use double-sided adhesive tape; the maker says it cannot guarantee secure attachment and makes the device easier to remove¹.
• Do not break off the perforated part of the mounting panel, which is needed to trigger the tamper if someone tries to dismantle the hub¹.
• Do not flip the hub when mounting it vertically; when properly fixed, the Ajax logo reads horizontally¹.
• Use the cable retainer clamp so the power and Ethernet cables cannot be pulled out on purpose¹.

If a device will not pair, switch it off for 5 seconds and try again¹. An admin or professional installer can add a device only while the system is disarmed¹. Firmware updates are enabled by default and run when a new version is available, but only when the system is disarmed and external power is connected to the hub¹.

The warranty on Ajax Systems Manufacturing products is valid for 2 years after purchase¹. Technical support, including an AI-powered chatbot and a professional support team, is available 24/7, and the maker states that technical issues can be resolved remotely in half of the cases¹.

Where the hub fits in a monitored system

The Hub (4G) Jeweller is the panel at the centre of an Ajax installation, not a complete alarm on its own. It needs detectors, and it needs somewhere for its alarms to go. If you are weighing up whether to have a monitored system at all, our guide to monitored alarms and receiving centres explains who responds and when, and how police respond to intruder alarms covers what the police will and will not attend. For the wider choice of system types, start with burglar alarms: types and how to choose one.

Two features of this panel are worth understanding before you buy into the ecosystem. The PD 6662 wizard opens a step-by-step guide to setting the system up to comply with the PD 6662:2017 British security standard¹; it is a configuration aid, and whether your installation needs to meet that standard is a question for your insurer and installer. And the hub is certified to UL/ULC standards only in its Hub 2 Plus Jeweller and Hub 2 (4G) Jeweller versions, according to Ajax's HomeSiren manual¹⁴; that is a North American certification and does not replace the British standard question.

If the mobile side is your reason for choosing this model, read our guide to alarms and cameras on a weak mobile signal or slow broadband before you commit to a position for the hub. And if a power cut is your concern, keeping your home protected in a power cut sets the hub's 15 hours alongside what else in the house needs power.