When sizing uninterupptible power supplies, what does N+ 1 mean?

Answer 1

Give us another clue.

It usually means One more than you're already catering for. Depends on the context.

Answer 2

650 watts is plenty. Make sure it's a good reliable brand -- don't be using an cheapy $25 PSU on a rig like this. It'll blow up on you, literally. Search on Youtube for PSU explosion and you'll see that it happens quite frequently on China-made PSU's. >-Zotac 9800 gtx+ Bottleneck much? Your i7 rig deserves a much better card. If this computer is for gaming I would recommend a GTX 275 at the minimum. >-Two 160 GB Western Digital 5400 rpm hard disks 5400 RPM = outdated, slow drives. 7200 RPM is the norm on all desktops nowadays. I suggest going for WD Caviar Black drives if you want better performance, or even a SSD drive as your main OS drive, and a cheaper, slower drive as a backup.

Answer 3

It is to do with redundancy. If you need N supplies to cope with your maximum load, then N+1 means you add one more, so that if one failed, you can still supply your load. If you want more redundancy, you could go for N+2 or N+3,...

Answer 4

N+1 configurations have a second UPS system to back up the first.

Here's a good site which explains the N ratings and more on UPS capacity planning info:

http://www.findarticles.com/p/articles/mi_qa3922/is_200509/ai_n15614498

Answer 5

N+ is a way of offering some resilience too your installation. In this instance you have a backup UPS that will accept the load should the `main` unit fail.

Answer 6

one more than N