Grounding on granite island [RE-wrenches]
Ken Schaal
ken at commonwealthsolar.com
Sat Apr 7 13:50:48 PDT 2007
<x-flowed>
Gee Ray, that really ruins my afternoon-----
Bet it ruined yours more !
What was at the working end of your ground wire?
Thanks
Ken
----- Original Message -----
From: "Ray Walters" <walters at taosnet.com>
To: <RE-wrenches at topica.com>
Sent: Saturday, April 07, 2007 1:52 PM
Subject: Re: Grounding on granite island [RE-wrenches]
>
>
> We did an installation on a rocky mountain top in West Texas several
> years ago. Same thing: solid rock 6" below the surface. This system
> featured a 50 ft tall wind generator as well. We dutifully tied all the
> grounds together, ran copper outside of the conduit to enhance the
> conductivity to ground, put in polyphasor lightning protection, etc.
> A lightning strike apparently to the wind generator sent a surge through
> the grounding system that took out 2 SW4024s, the charge controller, the
> Omnimeter, and the Kohler control for the generator.
> After that, we ran a 1/2" steel cable ( that's what they had already)
> and ran it from our existing ground system a 1/2 mile to a steel cased
> well in the valley below. Seems to have done the trick, as we haven't had
> any trouble since. That is a lot of cable, but that was a lot of
> equipment taken out too.
>
> Ray Walters
>
>
> On Apr 7, 2007, at 5:44 AM, Ken Schaal wrote:
>
>>
>> Several years ago we designed and furnished an off grid 2 kw system for
>> an extremely remote research facility in Gabon, Africa. It is located on
>> a huge slab of rock in the middle of the rain forest ,with tall trees
>> all around, on the equator and miles from the nearest dirt road. Most
>> supplies were delivered by helicopter. All the buildings were built on
>> piers on the rock, so a Ufer was not an option. Shallow wet ground was
>> several hundred feet away at the edge of the rock and near a shallow
>> river. So we supplied a large sheet of recycled heavy gauge copper
>> roofing with copper grounding cable soldered to it, and several clamps
>> to attach a #4 copper ground wire from the array and inverters. Surge
>> protectors were of course built in to the Outback power panel . 302's I
>> think, probably should have used the really good one's from Polyphaser,
>> I think. Instructions were to bury this copper plate in as wet a place
>> ,and as deep, as possible. They have quite a few lightning storms. So
>> far they are quite pleased with the system, which powers the office and
>> kitchen, including refrigeration. IE; It hasn't been zapped yet !
>>
>> My questions to the assembled wisdom of this group are;
>> -- was this the best solution and/or could it be improved?
>> --During the dry season, should they be sure to keep wet the area where
>> it is buried ?
>> --Should a lightning protection system, like those used on houses, be
>> considered? Or is the marginal grounding point the main issue?
>> --What is the best way to test the effectiveness of the existing ground
>> system, including the path from PV panel to mounting system [ alum. rack
>> on wooden support structure] to ground wire across rock?
>> This wire by the way, was supposed to have been encased in latex
>> modified cement mortar to fasten it to the rock so the people and
>> elephants wondering thru camp wouldn't dislodge it !
>> --What else should be considered?
>>
>> Everything has to be shipped by container from NY. We have some smaller
>> systems leaving in several weeks, and if improvements are to be made,
>> this would be the time.
>>
>> Thank you in advance for your thoughts, and time.
>>
>> Ken Schaal
>> CommonWealthSolar,LLC
>>
>>
>>
>> ----- Original Message ----- From: "Phil Undercuffler"
>> <p.undercuffler at conergy.us>
>> To: <RE-wrenches at topica.com>
>> Sent: Friday, April 06, 2007 10:59 PM
>> Subject: RE: Grounding on granite island [RE-wrenches]
>>
>>
>>>
>>> Are they pouring concrete footers?
>>>
>>> Establish a Ufer ground by tying to the rebar in the foundation. Here
>>> in
>>> the dry Southwest, it's the preferred grounding method in the area --
>>> fast, easy, effective and very nearly free.
>>>
>>> Have the concrete sub bend up a piece of the footing rebar, and leave
>>> 9-10" exposed out of the slab in the area of the power system. Connect
>>> to it with a two piece grounding "saddle" clamp, which makes a bronze
>>> to
>>> steel connection, and keeps the copper conductor isolated from the
>>> steel.
>>>
>>> Of course, if they aren't pouring a concrete foundation this wouldn't
>>> help.
>>>
>>>
>>> ------------------------------------------------------------------
>>>
>>> Phil Undercuffler
>>> Technical Services Manager
>>> Conergy, Inc.
>>> 1730 Camino Carlos Rey Suite 103
>>> Santa Fe NM 87507 USA
>>> Office | 505.473.3800 x4841
>>> Fax | 505.473.3830
>>> www.conergy.us
>>>
>>> ------------------------------------------------------------------
>>>
>>> -----Original Message-----
>>> From: Michael Welch [mailto:michael.welch at homepower.com]
>>> Sent: Friday, April 06, 2007 10:57 AM
>>> To: RE-wrenches at topica.com
>>> Subject: Grounding on granite island [RE-wrenches]
>>>
>>>
>>> Hi gang I an email awhile back about a grounding question, and a
>>> follow-up phone call today.
>>>
>>> This fellow is building a PV/wind/generator system for small cottages
>>> on
>>> a solid granite rock out on Lake Huron. His earth grounding plan is to
>>> haul a big steel plate out onto the ice (will need to do this pretty
>>> soon) and let it sink to the lake floor as a way of grounding the
>>> system.
>>>
>>> Or he may be able to submerge a plate in his graywater pool.
>>>
>>> There is no more than 6 inches of earth above the granite on the
>>> island.
>>> He does not have access to the kind of equipment needed to drill deep
>>> holes in the granite, but he can drill 6 or so inches deep.
>>>
>>> His RE dealer has been no help because of the unusual nature of the
>>> problem, and he has not been able to get help from local electrical
>>> engineers and electricians for the same reason.
>>>
>>> He wants to know if he is doing this correctly, and what size plates to
>>> use, how many, and anything else you can think of.
>>>
>>> You can either respond here if you think it will be of interest to the
>>> list, or if you need more info and want to carry out an email
>>> conversation with him, let me know off list and I will get you his
>>> email
>>> address.
>>>
>>> Thanks in advance for your help.
>>>
>>>
>>> ------------------------
>>> Michael Welch
>>> Sr. Editor
>>> Home Power magazine
>>> www.homepower.com
>>>
>>>
>>> - - - -
>>> To send a message: RE-wrenches at topica.com
>>>
>>> Archive of previous messages:
>>> http://lists.topica.com/lists/RE-wrenches/read
>>>
>>> List rules & how to change your email address:
>>> www.mrsharkey.com/wrenches/etiquette.php
>>>
>>> Check out participant bios: www.mrsharkey.com/wrenches/
>>>
>>> Hosted by Home Power magazine
>>>
>>> Moderator: michael.welch at homepower.com
>>>
>>>
>>> - - - -
>>> To send a message: RE-wrenches at topica.com
>>>
>>> Archive of previous messages: http://lists.topica.com/lists/RE-
>>> wrenches/read
>>>
>>> List rules & how to change your email address: www.mrsharkey.com/
>>> wrenches/etiquette.php
>>>
>>> Check out participant bios: www.mrsharkey.com/wrenches/
>>>
>>> Hosted by Home Power magazine
>>>
>>> Moderator: michael.welch at homepower.com
>>>
>>>
>>>
>>
>>
>> - - - -
>> To send a message: RE-wrenches at topica.com
>>
>> Archive of previous messages: http://lists.topica.com/lists/RE-
>> wrenches/read
>>
>> List rules & how to change your email address: www.mrsharkey.com/
>> wrenches/etiquette.php
>>
>> Check out participant bios: www.mrsharkey.com/wrenches/
>>
>> Hosted by Home Power magazine
>>
>> Moderator: michael.welch at homepower.com
>>
>>
>>
>
> R. Walters
> Solarray.com
> NABCEP # 04170442
>
>
>
> --
> [Non-text portions of this message have been removed]
>
>
> - - - -
> To send a message: RE-wrenches at topica.com
>
> Archive of previous messages:
> http://lists.topica.com/lists/RE-wrenches/read
>
> List rules & how to change your email address:
> www.mrsharkey.com/wrenches/etiquette.php
>
> Check out participant bios: www.mrsharkey.com/wrenches/
>
> Hosted by Home Power magazine
>
> Moderator: michael.welch at homepower.com
>
>
>
- - - -
To send a message: RE-wrenches at topica.com
Archive of previous messages: http://lists.topica.com/lists/RE-wrenches/read
List rules & how to change your email address: www.mrsharkey.com/wrenches/etiquette.php
Check out participant bios: www.mrsharkey.com/wrenches/
Hosted by Home Power magazine
Moderator: michael.welch at homepower.com
--^----------------------------------------------------------------
This email was sent to: michael.welch at homepower.com
EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9.bWljaGFl
Or send an email to: RE-wrenches-unsubscribe at topica.com
For Topica's complete suite of email marketing solutions visit:
http://www.topica.com/?p=TEXFOOTER
--^----------------------------------------------------------------
</x-flowed>
More information about the RE-wrenches
mailing list