Many South Africans install a mini UPS during loadshedding expecting their internet to stay online—but sometimes the WiFi still turns off.
This is frustrating, especially if you bought the UPS specifically to avoid downtime.
The issue is usually not the fiber provider. It is almost always caused by incorrect setup, voltage mismatch, or incomplete power coverage inside the home.
In this guide, we explain why your WiFi may still go down during loadshedding and how to fix it.
You Are Not Powering the Fibre ONT
The most common mistake is powering only the router.
If the fiber ONT (the small wall-mounted box) is off, your internet connection will drop even if the router lights are still on.
Both devices must be connected to the mini UPS.
Wrong Voltage Output
If your router requires 12V and your UPS is set to 9V, it may switch on briefly and then shut down.
Always check the power adapter label:
Output: 12V — 1A or Output: 9V — 1A
Voltage must match exactly.
Your UPS Battery Is Too Small
If your UPS only lasts 45–60 minutes, it may not have enough battery capacity for your router and ONT combined.
Higher-performance routers use more power and drain small UPS units quickly.
The UPS Was Not Fully Charged
Mini UPS devices need time to recharge between outages.
If loadshedding happens twice in one day, the battery may not have recharged fully.
You Are Powering Too Many Devices
Some people connect:
• Router • ONT • TV box • CCTV system
This dramatically reduces runtime.
Mini UPS units are designed only for networking equipment.
How to Fix the Problem
Check router voltage
Confirm ONT is connected
Ensure correct output cable
Upgrade to larger capacity if needed
If your UPS is correctly installed and properly sized, your WiFi should remain stable during normal Stage 4 loadshedding.
Loadshedding has made reliable internet almost essential in South Africa. Many households have fiber installed, but during power cuts the WiFi immediately switches off—even though laptops and phones still have battery.
That is why mini UPS devices have become extremely popular. They are small battery backup units designed specifically to keep your router and fiber ONT powered when Eskom electricity goes off.
However, the biggest question people ask before buying one is simple:
How long will a mini UPS actually keep my WiFi running?
The answer is not the same for everyone. Runtime depends on your router’s power usage, the fiber ONT, and the battery size of the UPS itself. In this guide, we explain the real runtime you can expect in South African loadshedding conditions.
What a Mini UPS Actually Powers
A mini UPS does not power your whole house. It is designed only for low-power network devices.
Normally it powers:
• WiFi Router • Fibre ONT (the small fibre box on the wall) • Sometimes a mesh WiFi node
It does NOT power: • TVs • PCs • Gaming consoles • Microwaves
This is important because runtime depends on how many devices you connect.
Typical Power Usage of Fibre Internet Equipment
Most people don’t realize how little electricity their internet equipment uses.
Typical South African fiber setup:
Device
Average Power Use
Fibre ONT
6W – 12W
WiFi Router
8W–18W
Total
14W – 30W
This low usage is exactly why a mini UPS works so well during loadshedding.
How Mini UPS Battery Size Affects Runtime
The most important number on a UPS is mAh (milliamp-hours). This is the battery capacity.
General guideline:
UPS Size
Expected Runtime
8 800 mAh
2–3 hours
10 400 mAh
3–4 hours
15 600 mAh
4–6 hours
20 000 mAh+
6–10 hours
In Stage 4 loadshedding (2-hour outage), almost any decent mini UPS will keep your WiFi on the entire time.
Stage 6 (4-hour outage) requires a higher capacity model.
Real South African Runtime Example
Let’s use a normal home fiber setup:
• 12W router • 8W fibre ONT Total usage = 20W
A 15 600 mAh mini UPS typically runs this setup for about 5 hours.
That means: Stage 2 ✔ Stage 4 ✔ Stage 6 ✔ (most of the time)
This is why mini UPS units are one of the most cost-effective loadshedding solutions in South Africa.
Why Some People Get Only 1 Hour
If your UPS only lasts 1 hour, it is almost always one of these:
You did not connect the fibre ONT (internet still dies)
Wrong voltage cable used
Cheap UPS with fake battery capacity
Too many devices connected (like a TV box)
Mini UPS devices are built specifically for networking equipment—not entertainment systems.
How to Extend Mini UPS Runtime
You can significantly increase runtime by:
• Turning off unused mesh nodes • Disconnecting USB charging ports • Using a low-power router • Charging the UPS fully between outages
Also remember: after multiple loadshedding cycles in one day, runtime becomes shorter because the battery cannot fully recharge.
Can a mini UPS last 4 hours? Yes, but only higher capacity models (around 15 600 mAh or larger). Smaller units may only last 2–3 hours.
Does a mini UPS use a lot of electricity? No. They charge slowly and use less power than most household appliances.
Will a mini UPS damage my router? No. They are specifically designed for routers and provide stable voltage.
Do I need to power the fiber ONT too? Yes. If the ONT is off, your internet will not work even if the router stays on.
Final thought
For most South African households, a mini UPS is the simplest and cheapest way to keep internet working during loadshedding. The actual runtime depends mainly on battery capacity and how many devices you connect, but a good quality unit can easily cover typical Stage 4 outages and often most Stage 6 schedules as well.
Loadshedding has made reliable internet in South Africa a daily challenge. The moment the power goes off, fiber routers and ONT boxes shut down immediately, cutting off work calls, online classes, streaming, and even security cameras.
The problem is that many UPS units sold online are incompatible with South African fiber setups or do not last long enough to survive loadshedding stages. In this guide, we compare the best mini UPS devices available and explain which ones are actually worth buying.
Quick Comparison of the Best Mini UPS Units
UPS Model
What It Powers
Typical Runtime
Biggest Advantage
Who Should Buy It
Gizzu Mini DC UPS (36W)
Router + Fiber ONT
4–6 hours
Reliable all-round compatibility
Most households
UltraLAN Micro UPS
Router + Fiber ONT
3–5 hours
Very stable fiber reconnection
Fiber installations & offices
Volkano Mini UPS – Best Long Runtime
Router + Fiber ONT
6–8 hours
Longest backup time
Work-from-home users
Generic DC Mini UPS (Entry-Level)
Router + Fiber ONT
2–3 hours
Lowest price
Basic internet backup
Entry-level mini UPS units are often sold under different brand names in South Africa, but many share similar internal hardware. They are affordable and suitable for short outages, although runtime and build quality can vary.
Gizzu Mini DC UPS (36W) – Best Overall Choice
The Gizzu Mini DC UPS is one of the most commonly used router backup devices in South Africa and is widely compatible with fiber installations. It supports both 9V and 12V outputs, allowing it to power the fiber ONT and the WiFi router at the same time.
The device automatically switches to battery power when electricity fails, so your internet connection usually stays active without rebooting. For most households, it provides enough backup time to cover a normal loadshedding block depending on the power usage of the router.
Key Features
Powers router and fiber ONT simultaneously
Automatic switchover during outages
Compatible with most ISPs
Compact and easy to install
Pros
Reliable and widely available
Good balance between runtime and price
Suitable for most homes
Cons
Not the longest runtime during extended Stage 6 loadshedding
UltraLAN Micro UPS – Best for Fiber Stability
The UltraLAN Micro UPS is often recommended by fiber installers because of its stable voltage output. A stable power supply helps prevent the ONT from restarting when power returns, which can shorten reconnection time.
It is designed specifically for networking equipment and works well in homes where the fiber connection normally takes long to reconnect after loadshedding. While the runtime is moderate, its reliability makes it a good choice for users who depend on a stable connection for work or online meetings.
Key Features
Stable output designed for fiber equipment
Supports router and ONT
Fast automatic switching
Pros
Reliable connection stability
Good for work-from-home setups
Prevents repeated router restarts
Cons
Runtime slightly shorter than high-capacity units
Volkano Mini UPS (Router & Fiber Backup) – Best Long Runtime
The Volkano Mini UPS is intended for users who need longer backup time than basic entry-level router UPS devices. While mini UPS units all operate on similar principles, models with larger internal batteries generally provide extended runtime when powering a fiber ONT and WiFi router.
In practical home use, runtime depends heavily on the router’s power consumption. Low-power fiber routers can remain online for several hours, while high-performance routers will reduce the backup time. Because of this, a higher-capacity mini UPS can be helpful during repeated loadshedding periods, especially for work-from-home users.
Key Features
Powers router and fiber ONT simultaneously
Automatic switchover during outages
Designed for continuous internet connectivity
Pros
Typically longer runtime than basic units
Suitable for repeated outages
Good for remote work and online meetings
Cons
Still limited compared to a full inverter system
Recharge time required between outages
Generic DC Mini UPS – Best Budget Option
Entry-level mini UPS units are sold under various brand names in South Africa but generally use similar internal hardware. They are designed to power a router and fiber ONT for short outages at a lower cost.
They are suitable for light users who mainly want to keep messaging and basic browsing active during loadshedding. However, runtime and build quality may vary between brands, so expectations should remain modest.
Key Features
Low-cost backup solution
Plug-and-play setup
Works with most routers
Pros
Affordable
Simple installation
Good for short outages
Cons
Shorter runtime
Build quality varies by brand
How to Choose the Right Mini UPS
Choosing the correct UPS is more important than choosing the cheapest one. The wrong model may switch on but still leave your internet offline.
Before buying, check the following:
Voltage compatibility Your router label will show 9V or 12V. The UPS must match it.
Number of ports You need two outputs—one for the router and one for the fiber ONT.
Battery capacity Larger batteries last longer during loadshedding. Homes with frequent outages should consider at least 15,000 mAh.
Automatic switching The UPS must automatically switch to battery when power fails. Manual units defeat the purpose.
Will a Mini UPS Protect Your Router?
Yes. A mini UPS does more than just keep your internet online. It also protects your router and ONT from sudden power loss and power spikes when electricity returns.
Repeated hard shutdowns can shorten the lifespan of networking equipment. Because a UPS provides stable voltage and controlled shutdown behavior, it reduces the risk of damage and improves reliability over time.
How long does a mini UPS last during loadshedding?
This is the most important question before buying a mini UPS. Runtime does not depend only on the UPS itself—it depends on how much electricity your router and fiber ONT use together.
Most fiber setups in South Africa use two devices:
• Fibre ONT (the wall box) → about 6W–10W • WiFi Router → about 8W–15W
That means the average total power usage is around 15W–25W combined.
Because of this low power draw, a mini UPS battery can last much longer than people expect.
Here is a realistic estimate:
Small mini UPS (8 000–10 000 mAh): ± 1 to 2 hours
Medium mini UPS (12 000–15 000 mAh): ± 3 to 4 hours
Large mini UPS (18 000–20 000 mAh): ± 5 to 7 hours
Stage 4 loadshedding is usually 2 hours, while Stage 6 can be 2.5 to 4 hours depending on the schedule. A properly sized mini UPS should therefore be able to keep your internet online for an entire loadshedding block.
Which Mini UPS Should You Choose?
If you are unsure which model fits your situation, the decision mostly depends on how you use your internet during loadshedding.
For most households, the Gizzu Mini DC UPS is the safest choice because it works with the widest range of routers and fiber ONTs.
For work-from-home or online meetings, a higher-capacity unit like the Volkano Mini UPS is useful if outages are frequent.
For stability problems after power returns, the UltraLAN Micro UPS can help prevent connection resets.
For occasional outages only, an entry-level mini UPS is usually enough for messaging and basic browsing.
Choosing the correct UPS is more important than choosing the cheapest one, because compatibility determines whether your internet stays online.
Frequently Asked Questions
Can I install a mini UPS myself? Yes. Setup is simple: unplug the router power cable, connect it to the UPS, then connect the UPS to the wall outlet.
Will fiber reconnect faster with a UPS? Yes. Because the ONT never switches off, the fiber connection does not need to re-establish itself when power returns.
Do mini UPS units use a lot of electricity? No. They use very little electricity because they only charge a small battery and power low-wattage devices.
Is a mini UPS better than an inverter for internet only? Yes. Inverters are designed for many appliances. A mini UPS is cheaper and more efficient if you only want internet backup.
Final Verdict
A mini UPS is one of the most practical solutions for staying connected during loadshedding in South Africa. It requires no installation, no fuel, and works automatically when the power cuts. For most households, a mid-capacity unit around 15,000 mAh offers the best balance between runtime and affordability.
If your main goal is uninterrupted internet for work, school, or security devices, a dedicated router UPS is usually far more convenient than a generator or full inverter system.
