On 22/11/09 14:47, Adrian Brentnall wrote:

http://cpc.farnell.com/apc/bk650ei/u...apc/dp/CS14752

but they claim a backup time of 4 or 2 minutes

The APC page for the BackUPS CS 650VA gives

35 minutes for 100W/160VA load
15 minutes for 200W/320VA load
8 minutes for 300W/480VA load
5 minutes for 400W/640VA load