Discussion Overview
The discussion centers on the earthing requirements specified in AS2067, particularly focusing on the implications of Figures B5 and B4 regarding the connection of Earth cables from a high voltage (HV) substation to a remote transformer. Participants explore the necessity of this connection given the distance between the two locations and the potential risks associated with Earth Potential Rise (EPR) during faults.
Discussion Character
- Technical explanation
- Debate/contested
Main Points Raised
- One participant questions the need for connecting Earth cables between a distant HV substation and a remote transformer, suggesting that the potential equalization may not be necessary due to the distance.
- Another participant proposes that the assumption about distance being a factor may be incorrect, indicating that earthing may only be required when the substation and transformer are co-located.
- A participant references the Australian Standard and its basis on IEC 61936, mentioning measures to avoid transferred potential between high and low voltage systems.
- One participant discusses the effects of grounding the shield of a medium voltage cable at one end versus both ends, suggesting that grounding at both ends could mitigate potential risks.
Areas of Agreement / Disagreement
Participants express differing views on the necessity and implications of earthing connections between the HV substation and the remote transformer. There is no consensus on whether the distance negates the need for such connections or if other factors must be considered.
Contextual Notes
Some participants note limitations in accessing the full text of the Australian Standard due to paywalls, which may affect their ability to fully evaluate the requirements and implications discussed.
