41
votes
7answers
6k views

Why do we still use power supplies on datacenter servers?

Computers mainly need three voltages to work : +12V, +5V and +3,3V, all of them are DC. Why can't we just have a few (for redundancy) big power supply providing these three voltages to the entire ...
5
votes
1answer
98 views

Using more than 80% power on a circuit in a disaster scenario

We currently have two cabinets of equipment at our datacenter, and each cabinet is served by two 30A circuits. The facility is relatively new, and each circuit is (supposedly) redundant at the source. ...
1
vote
1answer
116 views

desperately need 110v from a 208v pdu [closed]

I'm in a bit of a pickle... We're moving a client's infrastructure to a colocation facility. We have redundant 208v/30amp PDUs. While installing today, we realized that the client had a small ...
18
votes
7answers
2k views

Using Y power cables in a datacenter

I've always assumed that using Y cables from the PDU to redundant PSUs in the same server was totally acceptable practice, however I was recently speaking to someone that said that their colo wouldn't ...
-4
votes
2answers
120 views

What's the deal with using unreliable green energy in datacenters? [closed]

The news say that Google now uses 48 MW of electricity produced by wind turbines to power one of its datacenters. I've always heard that "green" energy is great, but it is unreliable - wind doesn't ...
7
votes
3answers
569 views

Source of PDU De-Rating?

In researching PDU's I have noticed most cite a derated current at the 80% level. For example, 30A is derated to 24A: Tripp Lite: Raritan: Does anyone have anything that shows what agency this ...
3
votes
2answers
273 views

Wattage Per Square Feet as a Measurement

I am used to looking at collocation providers where in U.S. are given as AMPs per rack (assuming 120V). I am looking into a place that rents space for servers which is listed as: "250 Watts per ...
11
votes
2answers
1k views

Using 48v for servers

I'm currently in the middle of a process to specify and design a new server environment for graphics and video rendering. We know we want to use blades, and we're pretty sure of our vendor decisions. ...
0
votes
1answer
365 views

Server/Power supply AMP usage

I've been looking into getting some servers with co-location, I've worked with co-lo'd servers before but this is the first time I've actually a rack up. All co-lo' providers specify a limit on the ...
3
votes
2answers
299 views

Power reading 2 amps with 13 servers?

We have a rack in a data center and we became suspicious of running out of power. But our power bar says 2 amps! It has a live indicator, so it's not just one reading. Do you think there's something ...
1
vote
3answers
1k views

Is it possible to use mixed 110V / 208V power on a single server with dual power supplies?

Is it possible to run a dual power supply server with one PS plugged into 110V, and the other power supply plugged into 208V? We've asked the vendors and they say they've never tested it or some other ...
23
votes
6answers
5k views

Best practices for power cabling racks in DC

With network cables it is easy. I use velcro-ties, coloured cables, 0U vertical cable organizers from APC on side of the rack -- easy and neat. However with power cables it was always giving me ...
1
vote
3answers
2k views

Data Center Power Draw Calculation

I have a difficult time calculating the power draw of our upcoming server (Dell R710) and what that means in terms of how a data center will calculate power costs. Hopefully you can help shine some ...
2
votes
3answers
319 views

Monitoring server room power

I'm looking for a good way to audit the per-rack power utilization in an existing server room. Each rack is powered, for the most part, by a pair of single phase 30A/208v feeds. Is there something ...
7
votes
2answers
4k views

How to step down voltage from 208V to 110V

I have some racks that will be fed by 208V/20A circuits. These circuits will be conditioned and battery-backed by the facility in which these racks will live. 99% of the devices in the rack will be ...
8
votes
2answers
248 views

“Zinc Whisker” issues?

Good morning; We've been having intermittent power supplies failures in our data center that have been preliminarily attributed to "zinc whiskers". I'm just starting to read about them (I just ...
4
votes
1answer
1k views

PDU says to ground to rack with “thread making screw”.. this is impossible?

I'm trying to use the 'thread making screw' to ground my Dell PDU to the Rack, however the metal on the rack is impossibly hard. Is this even required? The included screws don't even seem "thread ...
6
votes
6answers
616 views

Data Center Design and Preferences

When either selecting a data center as a co-location facility or designing a new one from scratch, what would your ideal specification be? Fundamentally, diversified power sources, multiple ISPs, ...
6
votes
6answers
294 views

Things to consider when buying PDUs

I am thinking about getting new PDUs for my racks. I would like ones that are: Metered (Maybe remote monitored) Vertical Meet my power requirements (Voltage and amperage) Right number of outlets ...
5
votes
3answers
699 views

Calculating how Much Power is needed For Servers

How do I calculate how much power I need for my servers / switches / routers? This is needed when moving into a datacenter. I figure I should just add up the wattage on all the power supplies even ...
5
votes
7answers
843 views

Rackmount Power: NEMA 5 or IEC C14?

Here in the USA, most consumer power strips seem to make use of NEMA 5-20R connectors - they look something like this. However, in the rackmount/datacenter world, I see a lot of power distribution ...