Auxiliary grounding/ earthing for Isolators in substation.
Auxiliary grounding/ earthing for Isolators in substation.
(OP)
One of my friend asked me this question where he was wondering if a separate earthing design is done for isolators 220kV. These grounding/earthing are then connected to main grid. If it is done what practices are followed? He was calling this earthing as auxiliary grounding/ earthing.
If anyone practiced this kindly help
If anyone practiced this kindly help






RE: Auxiliary grounding/ earthing for Isolators in substation.
Regards
Marmite
RE: Auxiliary grounding/ earthing for Isolators in substation.
Normally For 400kV Switch Yard- Mesh Formed is LxW :: 1500mmX 1500mm spacing of rod @300mm this was beneath the isolator
Normally For 220kV Switch Yard Mesh Formed is LxW :: 1200mmX 1200mm spacing of rod @300mm which is beneath the isolator
If it is OK then what codes they might have followed?
RE: Auxiliary grounding/ earthing for Isolators in substation.
RE: Auxiliary grounding/ earthing for Isolators in substation.
The operators do more than just stand
RE: Auxiliary grounding/ earthing for Isolators in substation.
RE: Auxiliary grounding/ earthing for Isolators in substation.
I prefer to install a galvanized steel platform which rests on top of the finished grade and which is bonded not directly to the ground grid, but instead to the point where the ground grid connects to the switch lever ground strap. This ensures that the operators hands and feet are tied to the same electrical potential and can no longer be part of a shunt path.
RE: Auxiliary grounding/ earthing for Isolators in substation.
1. Auxiliary ground Grid should be bonded to Ground Grid where Grid connects the switch lever ground strap.
2. The purpose of this auxiliary ground is to keep potential of handle lever and ground at persons atep at same level.
3. Size 1200mmx 1200mm with 300 mm horizontal conductor spacing is just a standard practice and as it is connected to main grounding its size and conductor spacing normally dosen't vary with soil resistivities.
4. Also Size 1500mmx 1500mm with 300 mm horizontal conductor spacing is used at many places to take care of safe working space around equipment.
Please correct me if I am wrong in analysis anywhere.