Rules and Guidelines
Want to participate in the discussions? Please read our Community Rules and Guidelines. Need some help? Visit Support and Answers.

  • State Not Answered
  • Locked Locked
  • Replies 10 replies
  • Subscribers 34 subscribers
  • Views 763 views
  • Users 0 members are here
Options
You may also be interested in
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Ground Resistance

ebee
It used to be fag packet type approximation that when measuring the earth impedance that as a very very much rule of thumb starter for ten sort of thing.

approx 80% of the total figure between two fart away points might be made up of the area around the local rod/plate/tapes etc and the other 20% between that area and all the area between them up to the area surrounding the other earthing point.

What would be a sort of max in ohms between two extremely far points example two countries ? say England and New Zealand or Oz?
Parents
  • 0
    Zoomup:

    10,145, 332.378 Giga Ohms.


    Am I close?


    Z.


    It will more than likely be less! 


    Southampton to Auckland, New Zealand via Cape Town is roughly 17,000 km.


    The earth is criss crossed with telecommunications cables which are steel wire armoured. So there should be continuity between any two countries that have those cables terminated there.  As for its resistance, what is 17,000 km worth of armouring similar to that on steel wire protected underground cable. The armouring varies with location, ie near to land it is thicker for protection, less so for deep-sea.


    Looking at my Australia to New Zealand Trans-Tasman Telegraph Cable samples,circa 1876, these vary from about 3/4 inch to 2 inches overall diameter. The inner conductor looks like 7/.029 or 7/.036 whilst the armouring varies up to about 6 mm diameter per strand.

    Clive

     


Reply
  • 0
    Zoomup:

    10,145, 332.378 Giga Ohms.


    Am I close?


    Z.


    It will more than likely be less! 


    Southampton to Auckland, New Zealand via Cape Town is roughly 17,000 km.


    The earth is criss crossed with telecommunications cables which are steel wire armoured. So there should be continuity between any two countries that have those cables terminated there.  As for its resistance, what is 17,000 km worth of armouring similar to that on steel wire protected underground cable. The armouring varies with location, ie near to land it is thicker for protection, less so for deep-sea.


    Looking at my Australia to New Zealand Trans-Tasman Telegraph Cable samples,circa 1876, these vary from about 3/4 inch to 2 inches overall diameter. The inner conductor looks like 7/.029 or 7/.036 whilst the armouring varies up to about 6 mm diameter per strand.

    Clive

     


Children
No Data

Community Rules & Guidelines