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Cubzilla
October 17th 03, 11:38 PM
Hiya all

We are trying to install a 10K series Compaq/Hp cabinet to support an
EVA5000 the cab has 2 PDU's is it ok to feed the 2 PDU's from separate
phases or will this be a health & safety issue ie the potential difference
across the 2 phases could reach 480 volts.


any URL's to the info would be appreciated.


Regards Trevor

Larry
October 18th 03, 12:14 AM
Cubzilla,
I'd only use one phase for the entire cabinet for simplicity sake.

There's no reason to endanger anyone by trying to power this unit with phase
A, and that unit with phase B. :-(


Larry Wagar
Skagit Media Productions
(360) 854-0709
larry <at> skagitmedia <dot> com
www.skagitmedia.com
Featuring: Virtual Tours,
Database driven ASP sites,
ASP Hosting $8.25 month,
50% off for Non-Profits
MLS Real Estate Sites



"Cubzilla" > wrote in message
...
> Hiya all
>
> We are trying to install a 10K series Compaq/Hp cabinet to support an
> EVA5000 the cab has 2 PDU's is it ok to feed the 2 PDU's from separate
> phases or will this be a health & safety issue ie the potential difference
> across the 2 phases could reach 480 volts.
>
>
> any URL's to the info would be appreciated.
>
>
> Regards Trevor
>
>

Cubzilla
October 18th 03, 05:44 PM
Thanks for that Larry,

The problem is that the customer see's if one phase goes down the other
phase SHOULD keep the system going and that the UPS people have hinted that
the one phase may not support the 32amp max that the FULLY loaded cab could
demand.

I'm sure I read a document that covers the safety angle.


Regards Trev

Cubzilla is my sad on-line game sig

"Larry" > wrote in message
...
> Cubzilla,
> I'd only use one phase for the entire cabinet for simplicity sake.
>
> There's no reason to endanger anyone by trying to power this unit with
phase
> A, and that unit with phase B. :-(
>
>
> Larry Wagar
> Skagit Media Productions
> (360) 854-0709
> larry <at> skagitmedia <dot> com
> www.skagitmedia.com
> Featuring: Virtual Tours,
> Database driven ASP sites,
> ASP Hosting $8.25 month,
> 50% off for Non-Profits
> MLS Real Estate Sites
>
>
>
> "Cubzilla" > wrote in message
> ...
> > Hiya all
> >
> > We are trying to install a 10K series Compaq/Hp cabinet to support an
> > EVA5000 the cab has 2 PDU's is it ok to feed the 2 PDU's from separate
> > phases or will this be a health & safety issue ie the potential
difference
> > across the 2 phases could reach 480 volts.
> >
> >
> > any URL's to the info would be appreciated.
> >
> >
> > Regards Trevor
> >
> >
>
>

Larry
October 18th 03, 06:16 PM
> The problem is that the customer see's if one phase goes down the other
> phase SHOULD keep the system going
Very rarely will you lose only one phase. And if one phase is lost a
switching device will feed from another phase? This sounds a little
extravagant for the very few times it would be used. The conventional setup
is a UPS (for power filtering and short outages) and a generator (for long
outages).

> the UPS people have hinted that
> the one phase may not support the 32amp max that the FULLY loaded cab
could
> demand.
Then run 3 phase power into the cabinet. Just make sure all wiring is
clearly labeled.


(¯`·._.· £ãrrÿ ·._.·´¯)


"Cubzilla" > wrote in message
...
> Thanks for that Larry,
>
> The problem is that the customer see's if one phase goes down the other
> phase SHOULD keep the system going and that the UPS people have hinted
that
> the one phase may not support the 32amp max that the FULLY loaded cab
could
> demand.
>
> I'm sure I read a document that covers the safety angle.
>
>
> Regards Trev
>
> Cubzilla is my sad on-line game sig
>
> "Larry" > wrote in message
> ...
> > Cubzilla,
> > I'd only use one phase for the entire cabinet for simplicity sake.
> >
> > There's no reason to endanger anyone by trying to power this unit with
> phase
> > A, and that unit with phase B. :-(
> >
> >
> > Larry Wagar
> > Skagit Media Productions
> > (360) 854-0709
> > larry <at> skagitmedia <dot> com
> > www.skagitmedia.com
> > Featuring: Virtual Tours,
> > Database driven ASP sites,
> > ASP Hosting $8.25 month,
> > 50% off for Non-Profits
> > MLS Real Estate Sites
> >
> >
> >
> > "Cubzilla" > wrote in message
> > ...
> > > Hiya all
> > >
> > > We are trying to install a 10K series Compaq/Hp cabinet to support an
> > > EVA5000 the cab has 2 PDU's is it ok to feed the 2 PDU's from separate
> > > phases or will this be a health & safety issue ie the potential
> difference
> > > across the 2 phases could reach 480 volts.
> > >
> > >
> > > any URL's to the info would be appreciated.
> > >
> > >
> > > Regards Trevor
> > >
> > >
> >
> >
>
>

Cubzilla
October 18th 03, 08:25 PM
"> Very rarely will you lose only one phase. And if one phase is lost a
> switching device will feed from another phase?

The equipment in the cab ALL have dual power supplies that receive power
simultaneously. The supplies are connected to both of the PDU's if half the
power fails the supply to the other half is already there and the kit can
function correctly (from one PDU).


> Then run 3 phase power into the cabinet. Just make sure all wiring is
> clearly labeled.

The kit (PDU's) have a single phase cables coming out of them the cab is not
designed for 3 phase, the "tails" from the PDU go under the floor to the
power distribution from the UPS

Thanks anyway Larry

Spam Buster
October 18th 03, 11:25 PM
"Cubzilla" > wrote in message
...
| Hiya all
|
| We are trying to install a 10K series Compaq/Hp cabinet to support an
| EVA5000 the cab has 2 PDU's is it ok to feed the 2 PDU's from separate
| phases or will this be a health & safety issue ie the potential difference
| across the 2 phases could reach 480 volts.
|
|
| any URL's to the info would be appreciated.
|
|

See
ftp://ftp.compaq.com/pub/products/servers/proliantstorage/power-protection/TC021002TB-powercooling.pdf

Among others: page 8:
"HP recommends providing two 30-amp 208/230 single-phase circuits per rack.
Future high-density server environments may require up to two 50-amp
circuits per rack.
Although racks of equipment currently use single-phase power, it may be
necessary to switch to three-phase power or higher amperage as technology
changes. Customers should consider three-phase power when:
• the load exceeds 6 kVA
• a centrally-managed UPS solution is needed
• a single UPS solution to support the entire datacenter is warranted
Rack manufacturers provide wattage and BTU information in their product
specifications. For precise facilities planning, HP provides a ProLiant
Class, Rack/Site Installation Preparation Utility, accessible from the
Active Answers web page. This utility includes a Power Calculator for each
ProLiant server (Figure 7). ProLiant Power Calculators are macro-driven
Microsoft Excel spreadsheets developed for two purposes:
• to review server loading to determine the number of power supplies
required to provide redundant power supplies, and
• to approximate the electrical and heat load per server for facilities
planning."

etc etc