Re: DATACENTER: Cooling and Cost Data for Web Hosting Data Centers

[Dave Siegel <dave@globalcenter.net>]

> If you've got a room full of 12000's and 7500's, then you don't need to be
> asking questions about power consumption, you need to start your own power
> company.
> 
> It's all about averages.
> You take the AVERAGE power consumption of all the racks.
> But you knew that.
> Or, *ahem*, I hope you did.

It should be obvious based on my case study that I don't build datacenters, 
only the network portion of them.  ;-)  I'm more an IP geek than a facilities
geek (and gosh, I hope to stay that way!)

> Nevertheless, you don't (or, shouldn't) plan your power consumption with
> amperage anyhow.  Use kva.

I was responding to the issue of A/rack.  I still don't think 100A/rack
is unreasonable.  At some point, your fuses for your 110VAC whips come into 
play, and based on the ever increasing density of CPUs/rack and increasing
power requirements of telecom equipment (more optical connections & lasers
to power up/rack), going overkill is a good idea.

Dave

> (8.334A= 1kva)
> 
> It's late.  Bed time.
> 
> 
> On Wed, 8 Dec 1999, Dave Siegel wrote:
> 
> > > > Wouldn't 100A per rack be a good number? That's what I am using, then
> > > > aggregating actual as we grow i.e. I'm not installing full load of
> > > > 10 tonners everywhere, just half and adjusting as we fill an average
> > > > of 50-80Ksq.f
> > > 
> > > What?
> > > You've _got_ to be kidding.
> > > 100A per rack?
> > > Short of a small load bank, I don't know how you could do that.
> > 
> > A Cisco 12012 requires 2 -48VDC 60A circuits.  3 6509's require 6 20A 110VAC, 
> > and would fit in a single rack.  Larger routers require even more current.
> > 
> > I'm not a web server guy, but I'd imagine that 32 1RU PII's would consume
> > a fair amount of current oo.
> > 
> > 100A/rack seems like a reasonable specification.  It's cheaper to install
> > lots of power at the offset than it is to retrofit and run additional
> > power case by case after the facility is opened.
> > 
> > Dave
> > 
> > 
> 
> -- 
> Ken Woods
> kwoods@verio.net
> 
> 
> 


-- 
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