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reference:grounding [2013/03/08 10:54] – grounding renamed to reference:grounding Alan Sheareference:grounding [2018/05/28 22:29] (current) – external edit 127.0.0.1
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 If you live on sand like we do, use three ground rods (in several locations I've driven 3 rods deep, and they still pushed easily!). Ideally you want to get down to the water table. If you live on sand like we do, use three ground rods (in several locations I've driven 3 rods deep, and they still pushed easily!). Ideally you want to get down to the water table.
  
-If you cannot drive ground rods because the ground is too rocky, dig a trench at least 2ft (or as deep as possible) and at least 20ft long and lay a #2 bare copper wire in it. You could also smash up some charcoal to mix in with the backfill. If you go this route I think it better to lay a ring all the way around the building. You must use exothermic welding (cadweld), brazing, or compression connectors for underground connections (in order of preference, and compression connectors should probably be augmented with brazing). Solder connections are not safe on ground wires, because the solder might melt during fault conditions. Solder is also not good underground because of possible galvanic action from the lead. Tinned underground wires are fine.+If you cannot drive ground rods because the ground is too rocky, dig a trench at least 2ft (or as deep as possible) and at least 20ft long and lay a #2 bare copper wire in it. You could also smash up some charcoal to mix in with the backfill. If you go this route I think it better to lay a ring all the way around the building. You must use exothermic welding (cadweld), brazing, or compression connectors for underground connections (in order of preference, and compression connectors should probably be augmented with brazing). Solder connections are not safe on ground wires, because the solder might melt during fault conditions. Solder is also not good underground because lead and tin are sacrificial anodes and will pit and be gradually eaten or dissolved by galvanic action. This is also why tinned underground wires are not acceptable. 
  
-Another option is to cast your bare ground wire in concrete; this is called a "Ufer" ground. It is very effective in rocky soil, very dry soil, or right on rock. The wire should be completely embedded 2" inside the concrete. If you're putting in a building, lay this right in the foundation footings. It needs to be no more than 2" from the soil, and its ok for it to contact the rebar. Longer is better, it can even be a ring in the footer all the way around the building. A ufer ground is now the preferred primary ground terminal for new construction in the USA, mainly because its permanent and can't be undone. The tail on the ufer ground should be long enough to connect to your ground bar or electrical panel.+Another option is to cast your bare ground wire in concrete; this is called a "Ufer" ground. It is very effective in rocky soil, very dry soil, or right on rock. The wire should be completely embedded 2" inside the concrete. If you're putting in a building, lay this right in the foundation footings. It needs to be no more than 2" from the soil, and its ok for it to contact the rebar. Longer is better, it can even be a ring in the footer all the way around the building. A ufer ground is now the preferred primary ground terminal for new construction in the USA, mainly because its permanent and can't be undone. The tail on the ufer ground should be long enough to connect to your ground bar or electrical panel. Six inches of the copper wire should be insulated, covered with heat-shrink, or taped where it exits the concrete -- three inches inside and three inches outside -- to prevent the pH of the concrete from damaging the wire. (Inside the concrete, galvanic action does not continue once the concrete has cured.) 
  
 If you want to do it right but less expensive than a commercial ground bar, buy a piece of copper bar from McMaster Carr (listing below). Mount the ground bar on ceramic insulators, or use blocks of hardwood for standoffs. Its preferable that it not contact the wall. If you want to do it right but less expensive than a commercial ground bar, buy a piece of copper bar from McMaster Carr (listing below). Mount the ground bar on ceramic insulators, or use blocks of hardwood for standoffs. Its preferable that it not contact the wall.
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 ====Master Ground Bar=== ====Master Ground Bar===
 McMaster Carr - www.mcmaster.com McMaster Carr - www.mcmaster.com
-  * [[http://www.mcmaster.com/#8964K411|8964K411]] Copper (Alloy 110) bar, 1/8" x 2" x 12" -- drill 9/32" holes for bolts & standoffs + 
-  * [[http://www.mcmaster.com/#94335A151|94335A151]] Ceramic standoff, 3/4"x1"dia, threaded for 1/4"-20 (optional - could use painted wood block)+Basic Ground Bar  
 +  * [[http://www.mcmaster.com/#8964K411|8964K411]] Copper (Alloy 110) bar, 1/8” x 2” x 12” -- 318 kcmil equivalent((kcmil: 1/8" x 2" x 1273 = 318,250 circular mils)) 
 + 
 +Better Ground Bar 
 +  * [[http://www.mcmaster.com/#8964K22|8964K22]] Copper (Alloy 110) bar, 1/4" x 2" x 24" -- 636 kcmil ((kcmil: 1/4" x 2" x 1273 = 636.5 circular mils))
  
 Professional Ground Bar Professional Ground Bar
 +  * [[http://www.mcmaster.com/#88865K315|88865K315]] Silver-plated copper bar, 1/4" x 2" x 3ft ((Silver plating reduces oxidation resistance with age; although copper oxide is still a good conductor, silver oxide is a very good conductor. In contrast, Aluminum oxide is a very good insulator.)) 
 +
 +Mounting Hardware -- Drill 9/32" holes for bolts & standoffs
 +  * [[http://www.mcmaster.com/#94335A151|94335A151]] Ceramic standoff, 3/4"x1"dia, threaded for 1/4"-20 (optional - could use painted hardwood block)
   * [[http://www.mcmaster.com/#71375K79|71375K79]] Ground bar mounting kit (~$25)   * [[http://www.mcmaster.com/#71375K79|71375K79]] Ground bar mounting kit (~$25)
-  * [[http://www.mcmaster.com/#88865K315|88865K315]] Silver-plated copper bar, 2" x 1/4" x 3ft (~ $75) 
  
 +Cable Connection Hardware
 +  * One each bolt, nut & lock washer, & 2 washers per connection 
   * [[http://www.mcmaster.com/#92240A539|92240A539]] Stainless steel hex head cap screw, 1/4"-20 x 5/8", pk 50   * [[http://www.mcmaster.com/#92240A539|92240A539]] Stainless steel hex head cap screw, 1/4"-20 x 5/8", pk 50
   * [[http://www.mcmaster.com/#92673A113 |92673A113]] Stainless steel hex nut, 1/4"-20, 7/16" width, 7/32" height, pk 50   * [[http://www.mcmaster.com/#92673A113 |92673A113]] Stainless steel hex nut, 1/4"-20, 7/16" width, 7/32" height, pk 50
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   * Lightning Protection Institute Standard of Practice, ( have LPI-175 / 2004 edition) \\ How to design and install lightning rods & protectors   * Lightning Protection Institute Standard of Practice, ( have LPI-175 / 2004 edition) \\ How to design and install lightning rods & protectors
-  * Ideal Surge Protector Location for Lightning Protection - \\ http://www.nautel.com/support/technical-resources/tips-n-tricks/04-09-2012/ +  * **Ideal Surge Protector Location for Lightning Protection -** \\ http://www.nautel.com/support/technical-resources/tips-n-tricks/04-09-2012/{{:reference:04-09-2012_nautel_broadcast.pdf|PDF}} 
-  * Shields Up! (ferrite toroids) \\ http://www.nautel.com/support/technical-resources/tips-n-tricks/05-04-2011/ +  * **Shields Up! (ferrite toroids)** \\ http://www.nautel.com/support/technical-resources/tips-n-tricks/05-04-2011/ {{:reference:05-04-2011_nautel_broadcast.pdf|PDF}} 
-  * Staying Grounded - \\ http://www.nautel.com/support/technical-resources/tips-n-tricks/25-01-2011/ +  * ** Staying Grounded -** \\ http://www.nautel.com/support/technical-resources/tips-n-tricks/25-01-2011/ {{:reference:25-01-2011_nautel_broadcast.pdf|PDF}} 
-  * http://www.nautel.com/wp-content/uploads/2011/04/Lightning-Protection-Radio-Stations-Oct-1998.pdf +  * http://www.nautel.com/wp-content/uploads/2011/04/Lightning-Protection-Radio-Stations-Oct-1998.pdf {{:reference:lightning-protection-radio-stations-oct-1998.pdf|PDF}} 
-  * Installation Methods for Protecting Solid State Broadcast Transmitters Against Damage from Lightning and AC Power Surges -- Broadcast Electronics, Inc \\  http://members.rennlist.org/warren/ground.pdf +  * **Installation Methods for Protecting Solid State Broadcast Transmitters Against Damage from Lightning and AC Power Surges** -- //Broadcast Electronics, Inc// -- http://members.rennlist.org/warren/ground.pdf {{:reference:be_ground.pdf|}} 
-  * http://www.ipclp.com/html/2011_IPC_Product_Catalog_No._211.pdf +  * http://www.ipclp.com/html/2013_IPC_Product_Catalog.pdf  
-  * http://www.lightning.org/wp-content/uploads/2012/10/LPI-IP-Specification-Document-Long-form.pdf +  * **Lightning Protection Institute** -- References on standards, studies, applications \\ http://lightning.org/learn-more/library-of-resources/ 
-  * http://tech.laclef.org/Power_Protection/power_protection.html +  * http://tech.laclef.org/Power_Protection/Electrical_Installation_Guidel/electrical_installation_guidel.html  {{:reference:electrical_installation_guidelines_overseas.pdf|PDF}}} 
-  * http://tech.laclef.org/Power_Protection/Some_thoughts_on_Lightning_Pro/some_thoughts_on_lightning_pro.html +  * http://tech.laclef.org/Power_Protection/Some_thoughts_on_Lightning_Pro/some_thoughts_on_lightning_pro.html {{:reference:some_thoughts_on_lightning_protection.pdf|PDF}} 
- +  * **Concrete-Encased Ground Electrode or "Ufer Ground"** 
- +    * http://www.psihq.com/iread/ufergrnd.htm {{:reference:the_ufer_ground.pdf|PDF}} 
- +    * http://www.ashireporter.org/HomeInspection/Articles/New-Life-for-the-Ufer-Ground/1676?print=true {{:reference:new_life_for_the_ufer_ground___the_ashi_reporter___inspection_news_views_from_the_american_society_of_home_inspectors.pdf|PDF}} 
 +    * http://www.ecmag.com/section/codes-standards/what-ufer-ground {{:reference:what_is_a_ufer_ground_.pdf|PDF}} 
 +    *  
 +    *      
 +<blockquote>In our area we are allowed to dig a trench 20' long, install some 3" concrete dobbies to hold the wire off the dirt, lay a bare ground wire sized for the system [minimum #4 copper for concrete-encased electrode], get an inspection, then pour concrete over the ground wire. the concrete must surround the wire 3", bottom, sides and top, so you have at least a 6" x 6" x 20' long concrete buried 18" deep. (it takes about 10 to 12 dobbies to keep the wire off the ground)<cite>[[http://www.electriciantalk.com/f2/ufer-ground-1038/#post152255 |www.electriciantalk.com]]</cite></blockquote> 
 ===== Connections ===== ===== Connections =====
  
-  * [[Cadweld]] ([[exothermic welding]])+  * [[:cadweld|CADWELD]] ([[:exothermic-welding|Exothermic Welding]])
     * One Shot Plus can be shipped by air     * One Shot Plus can be shipped by air
-    * One size could be used with [[cadweld#telecom_lugs|sleeves]] to enable multiple wire sizes+    * One size could be used with [[:cadweld#telecom_lugs|sleeves]] to enable multiple wire sizes
     * $10 each     * $10 each
     * Control Unit/Igniter $135     * Control Unit/Igniter $135
  
-  * Eritech [[Hammerlock]]+  * Eritech [[:Hammerlock]]
     * Irreversible ground rod bond      * Irreversible ground rod bond 
     * Hammer strike locks the conductor to the ground rod      * Hammer strike locks the conductor to the ground rod 
reference/grounding.1362740084.txt.gz · Last modified: 2018/05/28 22:28 (external edit)

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