[RE-wrenches] Fwd: Grounding on a glacier??

[Larry Crutcher, Starlight Solar]

Hi Jay,

An interesting quandary indeed. My thoughts are to build a grid of  
radials with short ground rods at the ends, extending in all  
directions from the equipment. This approach does not use anything but  
wire, short ground rods and ground connectors so there is no equipment  
to fail or replace.

You have very low conductivity on the ice so static builds up. What  
you are trying to do is increase conductivity by equalizing  
(neutralize) the potential in the area around the communications gear.  
This is not really a grounding system but an effort to force all  
electrons to neutral in the immediate area. You want as many radials  
as possible in all directions from the comm gear. Make the radials as  
long as is practical but don't sacrifice number of radials for length,  
i.e. more is better. If you can leave materials behind, grow the  
radial network each time you have opportunity to bring in more material.

For SURE you want to bond all equipment together and test these bonds  
with a megohm meter to make sure they are potentially the same. Then  
attach the equipment stack to your radial system and megohm that bond.  
Use as wide a copper material as you can carry in.

If your problem is human contact, make sure you discharge to the  
radial network and bond yourself before touching any equipment. You  
can use a static wrist strap. A surge suppressor is useless if it has  
no ground reference to conduct to so I would not pursue that approach.

Example of radial system for RF purposes: http://harvesting.com/tower/photos/radials.jpg

That's my best guess on a solution. Let me know if you try this.

Kindest Regards,

Larry Crutcher
Starlight Solar
(928) 941-1660
Renewable Energy Products, Service and Installation

Mailing Address (NO SHIPPING):
11881 S Fortuna Rd.
#210
Yuma, AZ 85367

Shipping and retail store (NO MAIL):
2998 Shari Ave
Yuma, AZ 85365



On Jul 22, 2009, at 7:13 AM, jason pozner wrote:

>
>
>
> Hey all,
>
> I am trying to figure out how to mitigate problems found with a 12v  
> 500w simple DC system without a ground.  This system is at 14,500'  
> on Denali (Mt McKinly).  We experienced a somewhat "festive"  
> fireworks display on the 4th of July as static current from a storm  
> seemed to travel through one of the antennae, and energized some  
> radio equipment.  There is no grounded conductor, as there is no  
> grounding electrode, as there is no ground to put it in.  The camp  
> is situated on about 500' of glacial ice.  The conductivity of the  
> ice is questionable, and to make the puzzle a bit more fun the camp  
> is raised and taken down at the beginning and end of every climbing  
> season (Apr-July), though the site is the same.  The loads are  
> primarily for communications for search and rescue purposes, and   
> reliability, and simplicity are paramount.  I have been exploring  
> the avenue of a surge arrestorsThanks, and was wondering if any of  
> you could make a recommendation on a product that can either be  
> reset or cheap enough to have a few replacements on hand.   
> Everything is flown in or carried to the site, and repair/ 
> replacement needs to be simple enough so non-technical minded  
> personnel can perform and re-set the system.
>
> Thanks,
>
> Jay Pozner
> Nunatak Alternative Energy Solutions
> Crested Butte, CO
> (970) 349-3432
> nunatakenergy at gmail.com
>
>
>
>
>
> -- 
> Nunatak Alternative Energy Solutions
> Jay Pozner and Lena Wilensky
> (970)349-3432
> www.nunatakenergy.com
>
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