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 17 replies
  • Subscribers 32 subscribers
  • Views 2514 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

Cross sectional area of a protective conductors

MS01
Can someone give me a some advice on if we have a earth electrode system made up of the structural rebar when using the adiabatic equation to size of the bonding conductor comes out at 300mm. MY questions is does each bond need to be this size or can it be made up via a series of smaller bonds that are equal or exceed the 300mm requirement? My opinion is each bond needs to be this size to deal with the fault current as the direction it will flow is unknown. What are peoples thoughts? I cannot see anything in the regs on this.

Parents
  • Former Community Member
    0 Former Community Member
    The adiabatic expression wouldn't size the bonding conductor - only the main earthing conductor, from which you can derive the bonding conductor size depending on the earthing arrangements.


    300mm2 seems a fantastically large conductor to be using for bonding. It might be credible for earthing but would be unusual. As an example, it's perfectly feasible to operate a pair of 1.5MVA transformers with a combination of a single 95mm2 conductor and the transformer tails armouring. Assuming this is a fairly large installation, and if you really do need a 300mm2 conductor, then personally speaking, I would use two conductors if you have the opportunity to split up the electrode for testing in future - other than that, I would favour a single conductor  - although there is no reason not to use more, smaller conductors as long as you are assured they all stay in place


    Regards


    OMS
Reply
  • Former Community Member
    0 Former Community Member
    The adiabatic expression wouldn't size the bonding conductor - only the main earthing conductor, from which you can derive the bonding conductor size depending on the earthing arrangements.


    300mm2 seems a fantastically large conductor to be using for bonding. It might be credible for earthing but would be unusual. As an example, it's perfectly feasible to operate a pair of 1.5MVA transformers with a combination of a single 95mm2 conductor and the transformer tails armouring. Assuming this is a fairly large installation, and if you really do need a 300mm2 conductor, then personally speaking, I would use two conductors if you have the opportunity to split up the electrode for testing in future - other than that, I would favour a single conductor  - although there is no reason not to use more, smaller conductors as long as you are assured they all stay in place


    Regards


    OMS
Children
No Data

Community Rules & Guidelines