RE: Dual rackmountable power supply?

["Hannigan, Martin" <hannigan () verisign com>]

> -----Original Message-----
> From: owner-nanog () merit edu [mailto:owner-nanog () merit edu]On Behalf Of
> alex () pilosoft com
> Sent: Friday, April 22, 2005 8:07 PM
> To: Mike Sawicki
> Cc: nanog () merit edu
> Subject: Re: Dual rackmountable power supply?
>
>
>
> On Fri, 22 Apr 2005, Mike Sawicki wrote:
>
> > Do any of you know if there are companies who manufacture 1/2U
> > rackmountable PDU's that take AC from redundant sources?  I have
> > equipment at a colo that seems to have issues with one of the two
> > circuits in my cabinets about once a month.  Since it would 
> be a real
> > pain in the neck for me to retrofit every server with dual-ps, I was
> > thinking this could be a possible middle-of-the-road 
> solution. Thanks.
> This is called a "Static Transfer Switch". (Sometimes 
> "automatic transfer 
> switch", particularly for smaller units). Number of companies 
> make small 
> ones:
>
> http://www.baytechdcd.com/cgi-private/showprod?prod=F5-RPC
> http://www.baytechdcd.com/cgi-private/showprod?prod=ATS12-30
> http://twinsource.net/
> http://www.apc.com/products/family/index.cfm?id=14
> http://www.mgeups.com/products/pdt230/sts/psts/stsa.htm


I don't think you can place these on the pointy side
of conditioned power. They require utility, IIRC,
which means you also need to add in some UPS for the front
side to make it work right since utility will tend to take 
'switch hits' during peak as the utility moves load around. 

WRT to the flapping power circuit, blind guess, ask your
colo provider to measure the load at your breaker and if
it's fine then swap the strip and chords (twistlock or not)
back to the first JB.


-M<




--
Martin Hannigan                         (c) 617-388-2663
VeriSign, Inc.                          (w) 703-948-7018
Network Engineer IV                       Operations & Infrastructure
hannigan () verisign com