It’s the first question almost every Pretoria homeowner asks, and it’s the right one: when the power goes off, does my alarm still protect me? Because criminals know the schedule too — and a dark, quiet neighbourhood during load shedding is exactly when you want your system wide awake.
Here’s the honest, practical answer for Ajax.
The short answer
Yes — a properly installed Ajax alarm keeps working through load shedding. It’s designed for it. But “properly installed” is the important part: a lazy install can leave gaps that only show up the moment the power drops. Here’s what keeps it running, and what to check.
Why Ajax keeps working when the power’s off
Ajax is built with power failure in mind — which matters enormously in South Africa:
- The hub has a backup battery. When mains power drops, the hub keeps running on its internal battery for hours, so the system stays armed and alert.
- The sensors have their own batteries. Every motion sensor, door contact and detector runs on its own long-life battery — they don’t care whether your mains is on or off.
- It talks over cellular, not just your internet. This is the big one. Ajax can communicate over a mobile (SIM) connection, so even when your fibre router loses power, the alarm can still send alerts and signal armed response.
- The sirens have backup power too, so the alarm can still sound.
In short: mains off, alarm on. That’s the whole point of the design.
Where load shedding does catch people out
This is where a cheap or careless install shows its cracks. Ajax has the tools to survive load shedding — but only if they’re actually used:
- Relying only on WiFi for communication. If the system is set to talk over your home WiFi and there’s no mobile backup, then the moment your router loses power (which is instantly, unless it’s on a UPS), the alarm can’t reach you. The fix: a mobile/SIM communication path.
- No UPS on the internet gear. If you want to keep viewing cameras or using internet-based features during an outage, the router and any recorder need a small UPS. The alarm itself keeps working on cellular, but internet features need internet.
- A neglected backup battery. Backup batteries don’t last forever. An install with no maintenance can have a flat hub battery that nobody noticed — Ajax will actually warn you before that happens, but only if the system’s set up to.
Almost every “my alarm died during load shedding” story traces back to one of these — not to the alarm itself.
How we set Ajax up for load shedding
When we install Ajax in Pretoria and Centurion, we assume the power will go off — regularly — and build for it:
- A mobile communication path so the system stays connected without depending on your fibre.
- Hub and siren backup batteries sized and tested for real outage lengths.
- A UPS on the router / recorder where you want cameras and remote features to survive the outage too.
- Battery health monitoring so you get told early, not after a break-in.
Then we actually test it — pull the power and confirm the system stays armed and still reaches your phone.
What about armed response?
Because Ajax can signal over cellular, a triggered alarm can still reach an armed-response control room during load shedding — the exact moment you most need it. There’s no compulsory monthly fee to own the system; monitoring is an optional add-on, and it’s one we’d recommend for exactly this reason.
The bottom line
Ajax is one of the best alarm choices for South African conditions specifically because it’s built to keep working when the power isn’t. The hardware does its job. What determines whether your system stays awake through load shedding is the install — a mobile backup path, healthy batteries, and someone who tested it before handing it over.
If you’re not sure your current alarm would survive tonight’s slot, that’s worth checking before you find out the hard way.
Talk to us
We design and install Ajax alarms built for load shedding — cellular backup, tested batteries and, if you want it, armed-response monitoring — across Pretoria and Centurion.
See our full Ajax alarm systems in Pretoria, or get in touch for a free assessment.
Call: 082 060 6023
Email: info@access-tech.co.za
