I've decided to move most of my servers out of our closet at work and into a datacenter. All of our servers are 110v, however we're starting to purchase some new ones, and the datacenter tech recommended we opt for the 208v since it was cheaper for the cage we are getting.
I've looked up on most of our servers that we traditionally use 110v for, however they SEEM to all support 208v as well (HP DL360 g4, Dell 2850's, and Dell 2650's).
Is there anything wrong with putting all of these servers on 208v??
DL360's should handle 208v with no problems. They have auto-switching power supplies which'll handle the switch for you. Also, running at 208v is slightly more efficient than running at 120v. A few percentage points gained, which can add up for a server that routinely burns 300+ watts.
If the servers support 208v (and most do these days) then you'll be fine. The datacenter tech is correct, this will save you money as most data centers charge per amp for power and running your servers at 208v will reduce the number of amps you'll need to power the servers.
208v vs 220 v is a factor of how the voltage is derived from the transmission line; whether or not it's delivered as single-phase or three-phase.
I'm wondering why exactly 208 volt - from where came this digit 208 ?
In most of the Europe the voltage is 220 volt and this is a standart. As a standart it allows you to have a little deviation for example as a low minimum 200 volt and as a maximum 240 volt, but now one speaks about 208 volt as a standart voltage for equipment.
Why do you think that power supplies at higher voltage are more effective ? If we speak only for the voltages (ignoring ampers) I think that more effective will be conversion from 110 to 3, 5, 12 volt compared to 220 to 3,5,12 volt. When the gap between two voltages is low you will have low losses caused by conversion.
While 208v is definitely OK for most recent Dell hardware, and probably most Cisco, etc., double check everything you're planning to add to the cabinet. We've had two ugly surprises with 110v-only equipment on a 208v circuit.
One, an off-brand chassis hosting our voicemail system, simply couldn't take 110v. Nice smoky smell, and a weekend without voicemail.
The other was an older Dell workstation-used-as-a-server which had a physical switch that nobody noticed, which was still set at 110v. The guy who hooked that up connected the power cord to the strip first, then connected the cord to the machine. Bright flash and cracking sound right in his face. He was unharmed but seriously shaken.