Disadvantage of having high neutral grounding resistance

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SUMMARY

The discussion centers on the disadvantages of implementing high neutral grounding resistance in electrical systems, particularly in contexts where technicians manually short bus bars for maintenance. The current solid grounding setup is around 9.5 ohms, and the user inquires about the implications of increasing this to 1k ohm. Key concerns include the potential for increased fault current, which could exceed safe levels for technicians, and the necessity to adhere to strict industry codes to ensure safety and compliance.

PREREQUISITES
  • Understanding of neutral grounding systems
  • Familiarity with electrical safety codes and regulations
  • Knowledge of fault current calculations
  • Experience with transformer specifications and applications
NEXT STEPS
  • Research the implications of high resistance grounding in electrical systems
  • Study the National Electrical Code (NEC) regulations regarding grounding
  • Learn about fault current analysis and its impact on safety
  • Consult with electrical engineers specializing in grounding systems
USEFUL FOR

Electrical engineers, safety compliance officers, technicians involved in maintenance of electrical systems, and professionals working with transformer grounding solutions.

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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