UPS units keep computers, network equipment and servers running through power cuts, surges and voltage dips. Our range covers line-interactive, online (double-conversion), standby and rack-mount models, plus replacement batteries and accessories. Leading brands include APC, Eaton, CyberPower and BlueWalker. It suits home offices, small businesses and server rooms.
How to choose a UPS
Topology. Line-interactive is the most common type in our range and suits PCs, routers and small office kit, because it corrects minor voltage swings without switching to battery. Online (double-conversion) units supply a constantly regenerated output and suit servers and sensitive equipment. Standby (offline) units are the simplest and are enough for a basic desktop.
Capacity. Add up the wattage of everything you plan to connect and leave some headroom. Models in our range commonly run from about 1 kVA to 3 kVA, and the usable power in watts is lower than the VA figure on the box. A single PC and monitor needs far less than a small server cabinet.
Form factor. Tower units stand on the floor or under a desk, rackmount units fit a 19-inch cabinet, and some models can be used either way. Check the rack depth against your cabinet before ordering.
Outlets. Many units use C13 sockets for standard IEC power cables, and larger models add C19 sockets for heavier loads such as servers and switches. Others have Type E or Type F sockets, which take regular wall plugs. Make sure the sockets match your plugs, or budget for the right cables.
Input voltage range. A wide input window lets the UPS ride out low or high mains voltage without draining the battery. Where the mains is unstable, this protects the battery and extends its life.
UPS brands we carry
- APC: the Schneider Electric brand, best known for the Back-UPS range for home offices and the Smart-UPS range for servers and networks.
- Eaton: an electrical power specialist whose range includes line-interactive and online units, and which also owns the Powerware line.
- CyberPower: known for line-interactive tower and rack-mount units aimed at home offices and small server rooms.
- BlueWalker and PowerWalker: the German company behind the PowerWalker brand, with units from compact desktop models to online rack versions.
- Vertiv: a data centre power and cooling specialist, known for the Liebert range of online UPS systems.
- FSP Group: a manufacturer better known for PC power supplies, which also makes UPS units.
Also in our range: Qoltec, Conceptronic and Roline.
Line-interactive UPS and rack-mount UPS make up the largest subcategories, followed by online and standby units. You will also find UPS batteries and a small selection of accessories for replacing or extending existing systems.
UPS units: frequently asked questions
What is the difference between a line-interactive and an online UPS?
A line-interactive UPS passes mains power through and corrects small voltage changes, switching to battery only when the supply fails or drifts too far. An online UPS converts the incoming power to battery-backed DC and back to AC continuously, so the output is isolated from mains problems. Online units suit servers and sensitive equipment, while line-interactive is enough for most PCs and network gear.
What size UPS do I need?
Add up the wattage of all devices you will connect, then choose a UPS rated comfortably above that total. Check the watt rating as well as the VA rating, since the watt figure is the lower of the two. Leaving some spare capacity gives longer runtime and room to add equipment later.
How long will a UPS run during a power cut?
Runtime depends on the load and the battery capacity, and most units are designed to give minutes rather than hours. A lightly loaded UPS lasts noticeably longer than one near its limit. The main purpose is to let you save work and shut equipment down safely, or to bridge short outages.
How often should UPS batteries be replaced?
Sealed lead-acid UPS batteries commonly last around three to five years, depending on temperature and how often the unit discharges. Replace them when the unit reports a battery fault or runtime drops sharply. Many models take replacement battery packs, which our UPS batteries subcategory covers.
