Why Your Computer Needs an Uninterruptible Power Supply (UPS) — and How to Choose One

The lights flicker for half a second and the computer switches off, taking an unsaved report with it — and sometimes damaging Windows too. In Tbilisi that's a familiar story: brief outages, dips and voltage spikes happen regularly, especially in older districts and during thunderstorms. An uninterruptible power supply (UPS) solves the problem. But its role is broader than simply buying time to save your work.

What a UPS protects against

• Power cuts — the computer keeps running on the UPS batteries so you can save your work and shut down properly.
• Momentary interruptions — even a fraction-of-a-second cut that a light bulb barely shows can restart a computer. A UPS absorbs it.
• Dips and overvoltage — many models correct the voltage without switching to battery.
• Surges and electrical noise — built-in filtering protects the PSU and your equipment.
• Data corruption — a sudden shutdown during a write can damage files, the file system, a database or a Windows update.

Types of UPS

The output waveform matters too. Cheap units produce a "stepped" approximation of a sine wave. Many modern power supplies with active power factor correction don't cope well with it: the computer may shut down on the switch to battery, or the PSU may start whining. For such systems a pure sine wave UPS is the better choice.

How to size it

UPS capacity is stated in volt-amperes (VA) and watts (W), which aren't the same thing. Go by watts. Add up the real consumption of everything you'll connect and add 25–40% headroom. Typical figures:

• an office PC with a monitor — 100–200 W;
• a gaming PC under load — 350–700 W or more;
• router, fibre terminal, switch — 10–30 W;
• a CCTV recorder with cameras — 30–100 W.

Runtime depends on battery capacity. For a computer, 5–15 minutes is usually enough to shut down properly. For a router and internet connection you may want hours — in which case a separate small UPS or a model with external batteries is used.

What to plug in

First and foremost, the computer and main monitor. The router and your provider's equipment are well worth connecting too, so a brief power cut doesn't drop your internet or your video call. In a home with CCTV, connect the recorder and cameras so recording isn't interrupted. Many UPSs have two kinds of outlets — battery-backed and surge-only — with less important devices going on the latter.

Automatic shutdown

If a computer runs unattended — overnight, or in an office after staff have left — the UPS can be connected via USB and software set up to shut Windows down cleanly when the battery is about to run out. This is especially important for servers, computers running databases and CCTV recorders.

Maintaining a UPS

UPS batteries are consumables. They usually last 3–5 years, less in a hot room. Signs of wear: the UPS holds the load for much less time than before, beeps, reports a battery fault or fails to switch to battery at all during an outage. An old battery can swell, so timely replacement matters. A technician tests the battery's capacity under load and replaces it without the need to buy a new UPS.

What a technician does

1. Measures the real power consumption of your equipment.
2. Selects the type and capacity of UPS, taking account of your power supply and mains conditions.
3. Connects the equipment and tests it with a simulated outage.
4. Sets up automatic shutdown for a computer or server.
5. Tests and replaces batteries in existing UPS units.
6. If mains problems are frequent, recommends an electrician check the wiring.

A real example

An accounting firm in Saburtalo twice lost data in its bookkeeping software in one month after power cuts — the database was corrupted by sudden shutdowns. We installed line-interactive pure sine wave UPS units on the workstations and a separate UPS with automatic shutdown on the server. Since then, power cuts have passed without any consequences.

For a private house or country home with frequent, long outages, an ordinary UPS may not be enough. Then the options are inverter systems with large battery banks or a backup generator, which should be specified together with an electrician so that the switchover is safe and the wiring can take the load. A technician can advise which devices genuinely need to stay on during a long cut and size the system around them.

Let us choose and install your UPS

We work across Tbilisi around the clock, selecting power protection for homes and offices. Learn more on our electrician, components and CCTV pages.