How long Ajax devices operate on batteries, and what affects this

What you need to know about batteries

• A battery is a chemical source of energy that is affected by the temperature of its environment. The lower the temperature, the slower the chemical processes, and the lower the battery capacity.
• There are two types of batteries: disposable and rechargeable. Almost all Ajax devices are equipped with disposable batteries. The exceptions are hubs and radio signal range extenders. As a backup power source, they use rechargeable batteries.
• Each device battery supports a specific type of cell: it is determined both by design and electronics. Installing any other type of cell may damage the device.
• Actual cell specs may vary from declared by the manufacturer. Even cells from the same batch can have different capacities, output voltages, or even be defective. Therefore, 100% of the cells are tested before installing in Ajax devices.

Batteries and communication with the hub

Ajax devices use a radio module to communicate with the hub. Depending on the distance between the device and the hub, the level of radio interference, or the presence of physical obstacles, the signal transmission power is adjusted automatically. The signal transmission power affects battery life directly.

The frequency of using the radio module by Ajax devices depends on the interval of polling by the hub and the number of alarms. The more frequently the device responds to central panel pings or transmits alarms to it, the faster the battery will drain. Using the Always Active function in the detector settings also reduces battery life.

Batteries in the glass break detectors

Using an electret microphone, this type of detector reacts to a sequence of sounds typical for breaking glass. When the detector is armed, the microphone monitors ambient sounds, consuming battery power to analyze input noise constantly. If the detector is always active and installed in a place with high noise pollution (near an open window on a noisy street or near working mechanisms), its battery life can be reduced up to two times.

Batteries in the opening detectors

Opening detectors are installed on doors and windows — typically, the places farthest from the hub — where the signal strength is low, and the temperature swings regularly. These detectors register every opening; hence the detector installed on the front door consumes battery faster than the detector installed on the window.

Do not install the detectors on the outer side of doors or windows, or in places where the temperature drops below an acceptable level (-10°C). If the Jeweller signal strength is low (one division), use the radio signal range extender.

Batteries in the motion detectors

The biggest amount of motion detectors battery is consumed by triggering and transmitting an alarm signal to the hub. The two settings that mostly affect the power consumption of motion detectors are Always Active and Delay When Entering. In the Always Active mode, the detector transmits motion alarms regardless of the security mode. When using the entry delay, the detector is triggered with every disarming: the hub simply ignores alarms until the time set by the user has expired.

Batteries in the sirens

Performing a sound is an energy-consuming process. The loudness of Ajax wireless sirens alarm can be from 80 to 113 dB. Each minute of energy consumption on such loudness is equal to several weeks of operation in passive mode. When using sirens to indicate security mode, keep in mind that the signals during arming/disarming, as well as LED indication, also consume a considerable amount of battery power.

Batteries in the fire and leak detectors

Ajax fire detectors battery consists of two primary and one backup cell. Fire detectors can operate independently of the hub, alarming with built-in sirens.

When the detector communicates with the hub, its radio module consumes energy. The shorter the device ping interval, the faster the battery will drain.

Built-in sirens consume a lot of energy; therefore, when calculating battery life, you need to consider the frequency and duration of alarms. For instance, FireProtect operates from built-in batteries for 4 years, but with the continuous signal of the siren, the primary cells will be dead in 7 hours.

When operating from the backup cell only, the detector does not activate the siren in case of alarm, sending the alarm signal to the hub only (if connected). For safety reasons, do not let the backup cell discharge completely. You can check its charge level in the detector settings in the Ajax app.

Batteries in the control devices

SpaceControl and Button consume battery power only for signal transmission: in passive mode, they do not communicate with the hub. They use smaller batteries and are more sensitive to temperature drops.

Batteries and the detector connection via integration modules

Transmitter can act as a power source for third-party detectors connected to it, so its battery life considerably depends on their energy consumption. When setting up the integration module, consider the operating mode of the connected detector: whether delays, night mode will be used, and whether the connected detector will be active 24/7.

When connecting Ajax devices through the ocBridge Plus integration module, using the Active 24 function will lead to detector reaction to all alarms even when the wired security system is disarmed (similar to the Always Active function in the Ajax security system settings). This mode shortens the detectors battery life.

When connecting ocBridge Plus to the wired control panel, use the IN terminal: this allows the integration module to monitor the armed mode and put the wireless detectors into power saving mode when the system is disarmed.

When and how to replace cells in the batteries

The Ajax system monitors the battery level in the devices and warns of the need to replace in advance. When the battery is on 10% of the charge approximately, the user receives a notification in the Ajax app, and a message about the malfunction is sent to the security company’s CMS each time the system is armed. Depending on the settings and conditions of use, the owner has to 2 months for replacing the batteries from the moment of notification.

If there are several cells in the detector battery, do not install cells of different models, manufacturers, or varying degrees of discharge. Due to the flow of charge between them, just one discharged cell can significantly reduce the life of the entire battery.

We recommend installing the following batteries to ensure that the Ajax device operates for the calculated time:

• Panasonic CR123A Industrial Lithium Battery, 3 V (item model number — 4330203048, manufacturer — Indonesia).
• Huiderui CR123A, 3 V, 1,600 mAh, LiMn02.
• Renata CR2032.
• Panasonic CR2032 (BAT487).
• Panasonic CR2032BS.
• Huiderui CR-2, 3 V, 850 mAh, LiMn02.
• Huiderui AA, 1.5 V, 2,900 mAh, LiFeS2.
• Energizer AA Ultimate Lithium, L91.
• Huiderui AAA, 1.5 V, 1,200 mAh, LiFeS2.
• Energizer AAA, 1.5 V, 1,200 mAh, LiFeS2 Lithium bulk.

If other batteries are installed, the operating time may differ from the calculated time.

Calculating battery life of Ajax devices

Many factors affect the device’s battery lifespan. Using the battery life calculator, you can make a theoretical estimate of the device’s battery lifespan based on these factors.

What you need to remember about Ajax devices batteries

• The battery life is affected by a set of factors, which makes its calculations always approximate.
• Always take into account temperature swings at the installation place of the detectors.
• Do not activate settings that use the detector radio module more frequently, unless it’s necessary. We are talking about the Always Active mode and reducing the detector ping interval.
• Use only recommended cells. Replace the whole battery only, using the same type of cells produced by one manufacturer.