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How to test a 1.5 pound magnesium anode

  1. Apr 10, 2015 #1
    Hello my name is Mike Moore and I work for Copperhead Industries, LLC We are a tracer wire manufacture for the underground non-metallic pipe utility sector, natural gas, water, sewer and telecom. We use magnesium anodes for grounding out the far end of the tracer wire system which completes the electrical circuit needed to carry the tracer wire signal.

    My question, I need to know where or how you can test a 1.5 pound magnesium anode that's used for grounding of tracer wire and not cathodic protection. What I'm trying to find is would a 1.5 # verses a 1/2 # perform better in conductivity or signal strength. I know bigger anodes are better in corrosion protection, but does it matter in conductivity? Does distance of a tracer wire locate signal get stronger with larger anode or does size not matter when it comes to grounding and conductivity? My thought would be the longer the anode the more surface we contact the better the ground. Would a larger anode last longer?

    Thanks for any guidance or answers!

    North American Sales Manager
  2. jcsd
  3. Apr 10, 2015 #2


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    Staff: Mentor

    Hi Mike, and Welcome to the PF.

    What professional/regulatory standards apply? It sounds like there should be some standards that would need to be tested to, no?
  4. Apr 10, 2015 #3
    No there is no standard for grounding of tracer wire, but it is starting to get traction accross North America. The problem for us is finding a way to test the conductivity. To understand tracer wire a little more go to www.mrwa.com and scroll down middle of page and click on tracer wire spec/ installation guide. What is the difference in cudutivity from heavy long skinny anode to fat short anode? Does greater/ more earth surface contact make greater conductivity? Would a 1.5# anode 16" lomg be better then 1/2# 6" long? Thanks for input! - Mike
  5. Apr 11, 2015 #4


    Staff: Mentor

    Wouldn't the conductivity depend much more on the shape and surface area than the weight?
  6. Apr 11, 2015 #5


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    Gold Member

    I work as an electrician and we use a "ground resistance tester" when we have questions of a ground being adequate.
    Our unit is a fluke, but almost any quality tester manufacturer makes them. A little pricey ($1400 and up ), but indispensable
    when evaluating an installation. You can set up a test with differing length rod next to each other and see where the point is where more
    rod doesn't give you any less resistance.
    In electrical a minimum 6' in contact with soil(90 degree angle to the ground) is required, but ground rods (copper or galvanized steel) come in 8' minimum( so you can drive them at up to 45 degrees to the ground).
    Just google ground resistance tester.
  7. Apr 11, 2015 #6


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    Gold Member

    You are absolutely correct. The deeper it reaches down into the moist soil, and the more "salts" in the soil, the better the ground.
    If we test a ground installation and it is not low enough resistance there is a method of lowering it using salts. Don't have to do that very often though.
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