Load Shedding and Your Security System: Stay Protected
How load shedding cripples alarms, CCTV, electric fences and gates in SA, plus practical UPS, battery and LTE backup advice with indicative Rand prices.
Load shedding does more than spoil your dinner and reset your microwave clock. Every stage of rotational cuts quietly switches off the layers of protection most South African homes and businesses rely on, often at the exact moment criminals are most active. The good news is that a security system designed for our power reality can ride through outages almost invisibly, and it usually costs less than people expect.
This guide walks through which devices fail when the lights go out, how backup batteries actually behave, how to size a UPS or inverter for security gear, and a practical checklist to keep yourself covered.
Why load shedding is a security problem, not just an inconvenience
When an area goes dark, several things happen at once. Outdoor and motion-sensor lighting dies, electric fences stop pulsing if their batteries are flat, cameras and recorders cut out, and the internet connection that carries your alarm signals goes down with the local fibre cabinet. Criminals are well aware of the published schedules, and a predictable window of darkness with disabled security is a gift.
The core issue is that most security equipment was designed for brief, occasional power failures, not the relentless cycle of cuts that has become normal. Backup batteries meant to bridge a 20-minute outage are now asked to carry multiple hours, day after day, and they simply do not last.
Which security devices fail when the power drops
Alarm panels and sensors
Your alarm panel has a built-in backup battery, usually a 7Ah sealed lead-acid (SLA) unit. A healthy battery powers the panel for several hours, but runtime depends on the number of zones and especially the radio/GSM communicator. Transmitting signals draws far more current than sitting idle. The bigger problem is degradation — load shedding deep-discharges the battery on repeat, so a two-year-old battery that should give eight hours may collapse to under an hour.
CCTV cameras, NVR and DVR
CCTV has no internal battery. The cameras, recorder and network switch all need mains power or a backup source. Even where the recorder keeps writing on a UPS, a powered-down router means no remote viewing and no off-site cloud backup. Professional CCTV installers will size a dedicated backup for the whole camera chain.
Electric fence energiser
An electric fence energiser runs off mains with a backup battery. A fence with a flat energiser battery is just decorative wire — and the app may still show "armed" while delivering no pulse. Reputable electric fence installers check energiser battery health at every service.
Gate and garage motors
Most modern motors include a backup battery so you are not locked out. These are small and degrade with cycling. A gate stuck open is both a security risk and an obvious signal that the power — and possibly your other defences — are down.
Router, fibre ONT and beams
This is the layer most people forget. Your fibre ONT and WiFi router have no battery. When they lose power, your alarm app, remote camera access and any cloud-based CCTV monitoring go dark. Worse, the fibre cabinet in your street is often on the same feed, so the whole link can be down regardless.
How backup batteries work and why they degrade
Almost all security backup batteries are sealed lead-acid (SLA/AGM) units rated in amp-hours (Ah). The catch is depth of discharge: SLA batteries are happiest near full charge, and every deep drain shaves a little life off. Lithium (LiFePO4) batteries tolerate deep cycling far better and last several times longer, at a higher upfront cost.
A practical rule for SA: budget to replace SLA security batteries every 2 to 3 years, and realistically closer to 18 to 24 months if you are getting hammered by frequent stages.
Sizing a UPS or inverter for your security gear
You do not need to power your whole house — only the security layer. List the devices you want to keep running, then choose a backup that comfortably covers that load for the longest realistic outage.
Treat all prices below as rough estimates that vary by brand, battery chemistry and installation.
| Device | Backup needed | Typical runtime / indicative cost |
|---|---|---|
| Alarm panel + sensors | Healthy SLA battery (7Ah), replaced every 2-3 yrs | 4-12 hrs; replacement battery R250-R600 |
| WiFi router + fibre ONT | Small router UPS (mini DC UPS) | 4-8 hrs; R600-R1,500 |
| CCTV (cameras + NVR + switch) | UPS or small inverter sized to load | 1-4 hrs on a 600-1000VA UPS; R1,500-R4,500 |
| Electric fence energiser | Built-in battery, replaced every 2-3 yrs | Several hrs; replacement battery R350-R900 |
| Gate / garage motor | Motor backup battery | 5-20 cycles; replacement battery R350-R800 |
| Whole security layer | Lithium/AGM inverter + battery bank | Many hrs to all-day; R8,000-R25,000+ installed |
Keeping your internet alive for monitoring
If you rely on app notifications or off-site CCTV monitoring, internet uptime is non-negotiable. A router UPS keeps your own equipment powered, and an LTE failover SIM in a dual-WAN router automatically switches to mobile data when fibre drops. For a monitored alarm, also confirm your panel uses a radio or GSM communicator so a flat ONT does not cut your link to the control room. Your alarm installer can confirm which path your signals take.
Criminals exploit outages, so plan for them
Treat every scheduled slot as a predictable risk window. The defence is redundancy: layered backup power so that even if one device fails, the others still detect, deter and report. A backed-up alarm that still phones the control room, a fence that still bites, and cameras that still record off-site turn a vulnerable window into a non-event.
Your practical load shedding security checklist
- Test every backup battery. Alarm, fence energiser and gate motor batteries all age. Replace any that struggle or beep low-battery warnings.
- Know your battery ages. Write the install date on each battery and diarise replacement at the 2-year mark.
- Back up your internet. Add a router UPS and, ideally, an LTE failover SIM.
- Protect the full CCTV chain. Cameras, recorder and network switch on backup — not just the NVR.
- Confirm your alarm's signal path. A GSM or radio communicator keeps you connected even when fibre is down.
- Right-size your inverter. If adding home backup anyway, include the security load in the calculation.
- Service regularly. Use a PSIRA-registered company and book routine maintenance.
- Compare before you buy. Backup costs vary widely, so get more than one quote.
A security system is only as reliable as its weakest battery. With load shedding now a permanent feature of South African life, the homes that stay protected are the ones that planned for the dark instead of being caught in it.
Ready to load-shed-proof your security? Compare PSIRA-registered installers and backup specialists on our company directory, or request a free quote and let vetted providers tailor a solution to your home or business.
Frequently asked questions
How long does my alarm panel battery last during load shedding?
A healthy 7Ah backup battery typically powers a standard alarm panel for 4 to 12 hours, depending on the number of sensors and whether the radio communicator is transmitting. An ageing battery may only manage 30 to 60 minutes, which is why many stage 4 to 6 outages catch homeowners off guard.
Will my CCTV keep recording when the power goes off?
Only if the cameras, NVR or DVR, and the network switch are all on backup power. A small UPS or inverter sized for your CCTV load will keep them running, but if your router or fibre ONT is off, you lose remote viewing and off-site recording even if the local NVR keeps writing to its hard drive.
How often should I replace my alarm and electric fence batteries?
Replace sealed lead-acid backup batteries roughly every 2 to 3 years. Frequent deep discharges from load shedding shorten that lifespan considerably, so many SA households now replace them every 18 to 24 months. A monitoring company can test battery health during routine service visits.
Do I need a UPS or a full inverter for my security gear?
For an alarm, router and a couple of cameras, a small 600 to 1000VA UPS or a dedicated 12V backup is usually enough. For a full CCTV system plus an electric fence and gate motor, a larger inverter with a lithium or AGM battery bank makes more sense and can carry the load through extended stages.
Why do burglaries increase during load shedding?
Outages create darkness, disable alarms and electric fences with flat batteries, knock out cameras and internet, and mask the sound of forced entry. Criminals know the schedule too, so the load-shedding window is a predictable opportunity unless your security is properly backed up.
Does keeping my router on a UPS really help security?
Yes. Without internet, your monitoring company and your phone app stop receiving alarm signals and camera footage, so an alarm may trigger locally with nobody alerted. A small router UPS plus an LTE failover SIM keeps signals flowing even when fibre infrastructure in your area is also down.