Intrusion Alarm Systems in Algeria: A Technical Guide That Skips the Sales Pitch

A poorly designed alarm system can be worse than no system at all. It creates false confidence, triggers constant nuisance alerts, and within three months the owner disables it themselves. This guide covers what actually makes a system hold up — under Algerian conditions, with power cuts, unreliable internet, and thick concrete walls that swallow radio signal.

1. Wired vs wireless: what actually matters in Algeria

This question comes up on every project, and the answer depends on the building, not on preference.

Wired means zero battery dependency and a rock-solid signal. But running cable through every partition wall is only practical during construction — retrofitting an existing building is a different proposition entirely.

Wireless (Ajax) installs fast and adapts to any layout, no drilling required. Ajax's Jeweller technology runs on a proprietary 868 MHz radio band with AES-128 encryption. Range is rated at 2,000 meters in open air — inside a typical Algerian concrete building, expect 200-400 meters in practice. A single Hub manages up to 100 devices.

What we spec on our projects: the Ajax Hub 2 (dual-channel, GSM + Ethernet) with MotionProtect detectors and DoorProtect contacts. This is the system we install in corporate offices, villas, and clinics.

2. How an Ajax system actually works behind the catalog page

The Hub is the brain of the system. It talks to sensors via Jeweller and to the outside world through two simultaneous channels: Ethernet and a SIM card (GSM/3G). If the internet drops — which happens regularly in Algeria — the Hub switches to GSM automatically. If someone cuts the Ethernet cable, GSM takes over within 30 seconds.

• Hub 2 — central unit, dual communication channels, 36-hour backup battery
• MotionProtect — PIR motion detector, 12m × 90° range, pet-immune up to 20kg
• DoorProtect — magnetic contact for doors and windows, 0.15-second alert latency
• HomeSiren — 105 dB indoor siren with anti-tamper protection
• StreetSiren Fibra — outdoor siren with LED strobe, IP55-rated, 4-hour backup battery

3. Zoning: the single most overlooked design decision

An alarm system without intelligent zoning generates false alerts until the owner gives up on it entirely. Zoning means defining who can move where, and when, without setting off the alarm.

Real example: a corporate site in Constantine. The system arms at night. The night guard does rounds at 3am. With every zone live, the alarm fires on every pass. The fix: a dedicated "guard circulation" zone that deactivates during rounds, with a predefined path and a 90-second delay to reach the arming panel.

Zone configuration in the Ajax app takes five minutes. Designing the zones properly takes 30-60 minutes of conversation with the client before installation — time most installers skip.

4. Backup power: realistic sizing

Power cuts in Algeria can run for hours. The Ajax Hub 2 carries a 36-hour rated battery — with no sirens or detectors active. In real-world use with active sensors, expect 12-18 hours depending on configuration.

For critical sites — clinics, institutional buildings — we add a dedicated backup supply with a 12V/18Ah AGM battery to guarantee 24 hours through an extended outage.

5. Three mistakes that show up on almost every unqualified install

• GSM Hub with an empty SIM card. The Hub needs an active, funded SIM to serve as backup. How many installations have a SIM with zero credit sitting in the Hub? Most of the ones I audit.
• Detectors facing sun-exposed windows. Direct sunlight heat can trigger a false positive on a standard PIR. Ajax's MotionProtect has thermal compensation filtering — but only if it's oriented correctly to begin with.
• No post-install walkthrough test. After every installation, I walk the building with the client simulating a break-in point by point. It's the only way to confirm the system genuinely covers every entry point.