[ale] Linux technophile emergency tool kit

[George Allen]

The army uses 6 and 8 foot grounding rods for our field systems, with
typically a ~1in copper braid for the ground conductor. No doubt this has
nothing to do with consttruction code, but buried in the Army FMs you can
find info on measuring ground impedance, which types of salts increase
conductivity better, etc. A short example:
http://www.dtic.mil/cgi-binGetTRDoc%3FAD%3DADA311375&sa=U&ei=YVSmUZjfL5DW9ASFmoFo&ved=0CAkQFjAB&usg=AFQjCNE_6JWqeksQkXbJEl2za10QNbJ7XQ

I know good grounding makes a big difference with HF radio transmission,
and in avoiding electrocution if your running stuff like 60k generators. :)

But for the IT gear everything except laptops goes through UPSs, which are
also grounded.
 On May 29, 2013 12:17 PM, "Michael B. Trausch" <mbt at naunetcorp.com> wrote:

>  On 05/29/2013 11:41 AM, Ron Frazier (ALE) wrote:
>
> Regarding what you said in above, I've used anti static bands while I was
> in school at DeVry as well as some of the time when I was at Delta.
> Sometimes we had an anti static mat.  At home, I usually use the technique
> you mentioned of just grounding myself before touching anything.  With the
> computer sitting beside me on a chair, as it is now, sometimes it's hard to
> know what is, in fact, grounded.  The pc is connected to the wall outlet
> through a three wire circuit so, presumably, the chassis is grounded, even
> if the pc is off, through the mounting screws for the power supply.  I've
> also been known to touch the screw that holds on the faceplate of a light
> switch before doing work on electronics.  I know touching such screws
> sometimes creates a static spark to my finger in the winter, so I assume
> it's grounded, else, why would it want to spark.  The junction box is
> plastic, but it has a ground wire inside.  I have to be especially careful
> in the winter (when it's dry as you said).  Another alternative is a metal
> water faucet.
>
>
> Mostly correct.
>
> The power supply should have the Earth ground attached to its case.  That
> case of course comes in contact with the computer case, which we hope is
> metal.  Then, by extension, the whole case is grounded after the power
> supply is mounted.
>
> That ground is the same ground that your water pipes are attached to (that
> is, the Earth outside your home), at least if the wiring in your home is
> correct.  (Important to check that when you buy a house!  We bought ours
> and the inspector missed the fact that ground was, well, not grounded.)
> Never assume you have a good Earth ground in the electrical wiring.  If in
> doubt, use metal water pipes as close to the water utility as you can get
> (or better yet, verify your ground!).  While it is true that water is a
> conductor, I wouldn't trust anything past PVC to be properly grounded
> without a ground wire run between the metal "islands".  Besides, metal
> provides a much easier path to ground than water does.
>
> If you ever need to create a ground, you have to buy a long metal stake
> and put it in the ground and attach a thick enough wire to it.  No idea how
> long the stake has to be, or how thick the wire has to be, though.
>
>     — Mike
>
> --
>   [image: Naunet Corporation Logo]  Michael B. Trausch
>
> President, *Naunet Corporation*
> ☎ (678) 287-0693 x130 or (888) 494-5810 x130
>
>
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