[Beowulf] Re: Re: UPS & power supply instability (Robert G. Brown)

David Kewley kewley at gps.caltech.edu
Wed Sep 28 19:18:57 PDT 2005

On Wednesday 28 September 2005 12:19, Maurice Hilarius wrote:
> Robert G. Brown wrote:
> >If you discover that -- surprise -- the "PFC" supplies aren't, you
> > can either:
> Or, the proper answer, which is :
> d) Contact Dell, have them pick up their machines.
> Then buy hardware from a reputable vendor who deliver what they
> quoted, and who do not try to sneak substandard parts on orders to
> you.
> Discuss with your organizations purchasing and acquisitions
> department about their contract regulations and the associated
> penalties for fraud.

As the person who started this thread, let me be very clear:

Dell does not deserve any suggestions that they did anything wrong, 
least of all that they committed fraud or snuck substandard parts on 
our orders.  To the best of my knowledge, those suggestions are simply 
false.  (And outrageous without evidence to back them up.)

We were never told we were getting PFC supplies.  I said they're PFC 
supplies because both a Kill-A-Watt clone and the Liebert PDUs says 
that the load power factor is 0.99 or 1.00.  I have not looked at the 

At the time of the order, we had no knowledge that would lead us to 
believe that there would be any problem with the electrical supply.  
Knowing what we know now (leaving out the direct knowledge that there 
*is* in fact a problem), we'd *still* have no reason to expect a 
problem.  Everything looks very good, except when the current 
oscillates, and that oscillation is a surprise to us.  I won't 
speculate here whether Liebert or Dell "should have known" there'd be a 
problem, but it's quite possible that they had no way to know, either.

I suspect (in fact I'm nearly certain) that other, non-Dell power 
supplies would induce this same problem in this room.

One quick update: We finally had a high-level engineering conference 
call with Liebert this morning, at their instigation.  It was a very 
good call, and they're being very helpful.  I hope there'll be a 
workaround soon, but we may have to live with this problem for a while 


> With our best regards,
> Maurice W. Hilarius        Telephone: 01-780-456-9771
> Hard Data Ltd.  FAX:       01-780-456-9772
> 11060 - 166 Avenue         email:maurice at harddata.com
> Edmonton, AB, Canada       http://www.harddata.com/
>    T5X 1Y3

P.S. I suppose you can guarantee that Hard Data power supplies would not 
induce current oscillations in the room? :)  Didn't think so.

More information about the Beowulf mailing list