Power Cuts and Your Network

What matters in practice:

• Back up the whole path — ONT or modem, router, switch and access points; if any one is off, the network is down.
• A small DC UPS outlasts an AC mini UPS for a router and ONT drawing 15 to 25 watts.
• Surges damage routers more often than outages do — use a quality surge protector and test the backup monthly.

In Uganda, a router that is perfectly configured still goes dark when the power does. Many people lose internet during outages not because the ISP failed, but because the router, fibre terminal or switch lost power. A small backup solves that.

What needs backup power

Everything in the path between the wall and your device:

• The fibre terminal (ONT) or 4G/5G modem
• The router
• Any switch or PoE injector
• Access points, if they are powered separately

If any one of these is off, the network is down. Remember too that your ISP's local equipment needs power, so backup protects you only as far as the provider stays up.

Your options

Mini UPS (AC). A small uninterruptible power supply keeps routers running for a short period and also protects against surges. It is easy to buy, but it converts power twice, so it wastes energy and often gives only an hour or two for a small load.

DC backup (mini DC UPS or power bank). Many routers and ONTs run on 9V or 12V DC. A DC UPS or a suitable battery pack powers them directly and lasts much longer than an AC UPS for the same battery. Check the voltage and polarity of your device carefully before connecting.

Solar or inverter systems. If you already have an inverter, put the network equipment on it. For businesses this is the most reliable setup.

Estimating runtime

A simple formula: runtime in hours is roughly battery watt-hours divided by the load in watts, reduced by 15 to 30 percent for losses. A router and ONT together might draw 15 to 25 watts. A 100 Wh battery would therefore power them for several hours under good conditions. Check the actual wattage on the device labels.

Battery care

• Keep batteries cool and out of direct sun.
• Replace them every few years, since capacity fades.
• Do not mix old and new batteries.
• Test the backup monthly by unplugging mains.

Surge protection

Power surges damage routers more often than outages do. Use a quality surge protector, and consider protection on the Ethernet and coaxial lines for outdoor runs. Switch equipment off during storms where practical — our guide to protecting CCTV, POS, routers and servers from power surges goes deeper on this.

Recommendation

For homes, a DC UPS for the router and ONT is the best value. For businesses, put networking gear on an inverter or online UPS, and keep a spare router configured and ready. This kind of resilience is part of the Networks & Infrastructure work we do for offices and sites across Uganda.

Next Steps

Backspace Business Solutions sizes backup power for routers, switches and access points alongside the network itself.

Request a Free Site Survey to work out what needs backing up, for how long, and what it would cost.