I want to buy a ups that would power 10 c0mputers, how can I arrieve at...

[Clara H]

...the KVA or KW rating for that ups?

[woutie]

These days a pc can consume up to 200W on a 220V circuit, so ruffly you would need about 2000W or 2kVA. If I were you I will look at getting a 2,5Kva UPS for the switch over during power failure/dip and for future add ons.

[Marianna]

200Watt is the same, whether it is a 220V or a 110V supply.Then take a bit of "Power-On surge" into account, so my suggestion is 3kW (for 10 computers)Also consider: Cathode Ray Tube (CRT) Monitors need a bit more power than LCD monitor, by a factor 3.