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

Scott Granados gsgranados at comcast.net
Tue Sep 1 20:35:34 EDT 2009


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.

----- Original Message ----- 
From: "Seth Mattinen" <sethm at rollernet.us>
To: "Michael Ulitskiy" <mulitskiy at acedsl.com>
Cc: <cisco-nsp at puck.nether.net>
Sent: Tuesday, September 01, 2009 4:26 PM
Subject: Re: [c-nsp] Multiple power supply failures. Advise needed


> Randy McAnally wrote:
>> I'm sorry, but I highly doubt this is why his devices are failing.  Each
>> device receives ground through the power cord (3rd prong is there for a
>> reason, as well it is tied to chassis ground internally).  Secondly, the
>> cabinets themselves should be grounded as is the case in any proper 
>> facility.
>>  By fastening the chasis to the cabinet you are basically providing a 
>> second
>> ground path.  A third ground path is nice and pretty, but it isn't going 
>> to do
>> much if anything at all to help him in this case.
>>
>> Either the power is extremely dirty, or the facility as a while is not
>> properly grounded which means no matter how well he grounds his equipment 
>> it
>> won't help unless he digs his own ground.
>>
>
> Correct, the ground is the ground is the ground. The lug will let you
> beef it up and do a 6AWG or whatever instead of what's in the power
> cords, but the ground is tied everywhere. It has to be; it's a safety
> ground.
>
> Something really odd/fishy is going on at the facility in question.
> Either they have a problem and won't admit it, or they're just as
> baffled as you are. But there is obviously *something* very bad going on
> to fry power supplies like that.
>
> Which leads me to a question; has any of the stuff you've replaced
> become part of the fried PSU problem, or just originally installed
> supplies? One tells me they're lying and the power is even worse than a
> raw utility feed, the other says maybe you have metal particles (or
> something) building up from under the raised floor over time.
>
> ~Seth
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/ 



More information about the cisco-nsp mailing list