[c-nsp] Multiple power supply failures. Advise needed

[Michael Ulitskiy]

please see inline

On Wednesday 02 September 2009 12:40:30 pm Robert Johnson wrote:
> Coming from an electrical engineer:
> Before doing anything else, you need to get someone out there with a
> recording oscilloscope to verify the input power to your equipment. This is

That's what I have now sitting in my cage. Apparently this is what they call "unintrusive power monitoring".
Can't wait for the result.

> the best way to ensure that you are getting the proper waveform, and that
> your power is free from transients and sags. A normal managed UPS will not
> be able to pick up infrequent spikes, harmonic distortion, etc. These are
> all single phase 120 volt circuits, right?

Correct

> Grounding is unlikely to be the problem. As previously mentioned, the safety
> ground on the equipment power supply bonds the equipment chassis to the
> facility ground. This is adequate in a typical data environment that is not
> in a high lightning exposure zone. If you were in a telephone CO, a site
> with a communications tower, etc., then it would be worth your while to make
> sure that each piece of equipment and metal hardware was bonded back to the
> MGB. But based on the information you've given here, I don't think this is
> relevant to your power supplies blowing up.
> 
> I would go ahead and put some double sided tape on the air intakes for your
> equipment. After a few days, peel the tape off and take a look at it using a
> microscope or magnifying glass and inspect for metal particles.

Yes, I'm going to do something like that, thanks. Also I'm going to open a couple of raised floor tiles
and see how dirty it is over there.

> Robert
> 
> On Wed, Sep 2, 2009 at 11:08 AM, Michael Ulitskiy <mulitskiy at acedsl.com>wrote:
> 
> > What about the fact that most (if not all) power supplies have independent
> > sucking fan
> > and that power supply air flow is separate from the system board flow.
> >
> > Plus all system board I saw are covered with some insulating coating.
> > I've never pulled apart a modern power supply. I'd expect them to have
> > something like that too, but who knows?
> > Plus since PSU is the only part that's dealing with high voltages I expect
> > it to be more sensitive
> > to momentary shorts. Am I wrong?
> >
> > I'm expecting report for provider ordered unintrusive power monitoring.
> > I'm almost positive they won't find anything, though.
> > I'm still looking for advice on independent power analysis source in New
> > York, NY if anyone has this kind of experience.
> > Thanks,
> >
> > Michael
> >
> > On Wednesday 02 September 2009 10:29:07 am Randy McAnally wrote:
> > > Plain old dust wouldn't be so picky...it has to be ingested past the
> > system
> > > board before it hits the power supply in most cases.  System boards are
> > WAY
> > > more sensitive to this kind of thing.
> > >
> > > The fact you have ONLY PSU's failing still makes me think you have power
> > issues.
> > >
> > > --
> > > Randy
> > > www.FastServ.com
> > >
> > > ---------- Original Message -----------
> > > From: Michael Ulitskiy <mulitskiy at acedsl.com>
> > > To: "Randy McAnally" <rsm at fast-serv.com>
> > > Cc: "Scott Granados" <gsgranados at comcast.net>, "Seth Mattinen"
> > > <sethm at rollernet.us>, cisco-nsp at puck.nether.net
> > > Sent: Tue, 1 Sep 2009 23:21:23 -0400
> > > Subject: Re: [c-nsp] Multiple power supply failures. Advise needed
> > >
> > > > This is my main suspect now. They are doing work in the facility.
> > > > Not heavy construction, but they do install cages and cabinets for
> > > > new tenants and they're definitely using tools that  produce metal
> > dust.
> > > > My theory is that because of we've been the 1st customer who moved
> > > > into that facility we've been collecting that metal dust for longest
> > > > and so we're having a lot of problems with our equipment. To my
> > > > knowledge none of our neighbors are having the same problem, but
> > > > none of them have been in the place long enough. So the question
> > > > remains: is there any way to fight it/protect from it except from
> > > > going through the huge-huge-huge headache of undertaking another move?
> > > >
> > > > Michael
> > > >
> > > > On Tuesday 01 September 2009 08:48:38 pm Randy McAnally wrote:
> > > > > He mentioned he was one of the first customers in the colo so
> > > > > this might be a possibility
> > > > >
> > > > > --
> > > > > Randy
> > > > >
> > > > > ---------- Original Message -----------
> > > > > From: "Scott Granados" <gsgranados at comcast.net>
> > > > > To: "Seth Mattinen" <sethm at rollernet.us>, "Michael Ulitskiy"
> > > > > <mulitskiy at acedsl.com>
> > > > > Cc: cisco-nsp at puck.nether.net
> > > > > Sent: Tue, 1 Sep 2009 17:35:34 -0700
> > > > > Subject: Re: [c-nsp] Multiple power supply failures. Advise needed
> > > > >
> > > > > > Also make sure that the provider isn't doing work in the facility.
> > > > > >  I'll never forget going to an L3 datacenter and arriving to find
> > > > > > workmen in the overhead grinding away and dropping dust and who
> > > > > > knows what else in to all the racks below including a rack of Netra
> > > > > > T1's that promptly sucked in the dust and kicked out power
> > > > > > supplies.;)  It was definitely metal shavings because they were
> > > > > > using a grinding type tool up in  the over head frames.
> > > > > >
> > > > >
> > > > >
> > > ------- End of Original Message -------
> > >
> > >
> >
> >
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