Chuck is better on the theory, I have only been to a few R56 classes so I could be incorrectly remebering. The theory, again not my thing, is rooted in inductance and choke which increases resistence along the length of the cable traveling through the conduit. The faster the spike (strike) the greater the resistance. It can cause a conductor to blow apart. it applies to a conductor carrying a large surge. It has to do with the magnetic properties of all ferrous metals. According to the NEC, which the R56b standard pulls from in part is below and says you have to ground each end. I don't know if this is the exact language in the current NEC as I don't own a copy.
NEC Section 250.64(E) includes requirements to address such protection. If a grounding electrode conductor is installed in a ferrous metal raceway, the raceway must be electrically continuous from the point of attachment to the cabinet or equipment to the grounding electrode and must be securely fastened to the ground clamp or fitting. Ferrous metal raceways contain iron or steel content, and examples include rigid metal conduit (RMC), intermediate metal conduit (IMC) and electrical metallic tubing (EMT). These conduits and tubing have a magnetic property that reacts to rising and falling magnetic fields present in alternating current (AC) systems. Here are some examples: https://www.carelient.com/2018/12/21/grounding-electrode-conductor-nec-violation-example/ https://www.ecmag.com/section/codes-standards/guardian-ground I think I have previosuly posted a link to my dropbox with the R56. I am positive it is out of date but following it is better than not following anything. It has a lot of good illustrations and pictured to help clarify things as well. Here it is again: R56 manual <https://www.dropbox.com/sh/ppoo1zy8xw86w2c/AABBdaKgR37MVkJLl-jB-YKia?dl=0> The long and short of it is that is a lot easier to use PVC than ground each end of the metal conduit. On Wed, May 29, 2019 at 10:10 PM Jaime Solorza <[email protected]> wrote: > Hum..the number 6 ground cable is insulated...direct bonding to 10 ft. > ground rod. > Please explain your observation...I have had great success with this > method but open to improvements or corrections > Thanks > > On Wed, May 29, 2019, 9:02 PM Lewis Bergman <[email protected]> > wrote: > >> That conduit might serve as a choke on that ground. >> >> On Wed, May 29, 2019, 9:56 PM Jaime Solorza <[email protected]> >> wrote: >> >>> Site pro mount, PC-Tel antenna, Heliax cable and accessories. .inside >>> GE-MDS radio. 928.xxx and 952.xxx MHz. >>> -- >>> AF mailing list >>> [email protected] >>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>> >> -- >> AF mailing list >> [email protected] >> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> > -- > AF mailing list > [email protected] > http://af.afmug.com/mailman/listinfo/af_af.afmug.com > -- Lewis Bergman 325-439-0533 Cell
-- AF mailing list [email protected] http://af.afmug.com/mailman/listinfo/af_af.afmug.com
