×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Erico GEM

Erico GEM

Erico GEM

(OP)
Hi....

I have asked few questions about this grounding grid and it is still on going. We have decided to use Eric Ground Enhancing Meterial on the periphery of the ground grid. The  ground grid is in the middle of the rock. Excavated and backfilled with granular B. I am just wondering, to acheive the full advantage of GEM it should be buried at least 2.5 ft below the grade while the grid should be 1.5 ft as per the traditional practice. I was wondering, what advantage this GEM will offer conceptually.
I would apprecaite your word.

Thanks

RE: Erico GEM

Conceptually, the GEM around the periphery conductor will increase the effective diameter of the conductor.  This will reduce the resistance to current flowing into the rock.  I can see two reasons for favoring the use of GEM on the periphery conductor in particular.  First, the current density is higher in the periphery conductor so you get a greater relative advantage by reducing resistance where the current is higher.  Second, the periphery is where touch-potentials are usually higher.  The GEM will bring the surface area around the periphery closer to that of the grid and reduce touch-potentials.  

On the other hand, by reducing the relative resistance of the periphery, you may find that more of the fault current flows in the periphery than it would have without the GEM.  This would negate some of the advantage but would require a detailed analysis to predict the full effect.  You would have to have the ability to model the volume around the conductor at a different resistivity as the rest of the soil.
 

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources