Disadvantage of having high neutral grounding resistance

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Discussion Overview

The discussion centers on the implications of implementing high neutral grounding resistance in electrical systems, particularly in relation to safety during maintenance activities involving manual shorting of bus bars. The context includes considerations of fault current limits and compliance with industry codes.

Discussion Character

  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant inquires about the disadvantages of using high neutral grounding resistance, suggesting it may limit line-to-ground fault currents.
  • Another participant questions the feasibility of using a 1k ohm resistance, noting that typical values are around 9.5 ohms and expressing concern about fault currents potentially affecting technicians.
  • A different participant emphasizes the importance of adhering to applicable codes, indicating that design choices may be limited by regulatory requirements.
  • One participant requests clarification on the specific industry context, suggesting that the type of industry may influence the relevance of the discussion.
  • Another participant advises consulting a professional familiar with safety codes to prevent potential hazards to technicians.

Areas of Agreement / Disagreement

Participants express varying levels of concern regarding safety and regulatory compliance, with no consensus on the appropriateness of high neutral grounding resistance or the specific technical parameters involved.

Contextual Notes

There are limitations regarding the specific electrical codes applicable to the situation, as well as uncertainties about the operational parameters of the equipment in question.

Who May Find This Useful

Professionals in electrical engineering, safety compliance officers, and technicians involved in maintenance of electrical systems may find this discussion relevant.

nand arora
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I am working in an industry where my technicians have to short the bus bars on regular basis (manually) for some maintenance purposes.

I want to add high neutral grounding resistance to the incoming supply transformer to limit the Line to ground fault. Presently the neutral has been solidly grounded. What will be the disadvantages of high resistance neutral grounding?

We are using neutral for some (single phase) welding and grinding purpose.
 
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I have never seen any transformer with very high neutral grounding resistance. It is uaually around 9.5 ohms. Can I have 1k ohm resistance. What will be its disadvantages?

And yes, I do have an Earth fault relay in neutral. But still I don't want the fault current (which may pass through the technician's body in worst case scenario) to be more than 5 milli amps.
 
I don't know the specific answer to your question. But I think that this is an area where codes can be strict and you may not have much design freedom. My recommendation is to check the applicable codes first to see what is permitted.
 
I think you should further specify the type of that 'industry'. I were just about to reply something what I think would have been totally irrelevant judged by your posts on other topics.

What range of kilovolts and kiloampers?
 
Please consult with a professional who is trained in this area and knows the applicable codes and such. We do not want your technicians getting injured or killed because someone accidentally gave you incorrect information.

Thread locked for safety reasons.
 
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