Today I've see a news where an innocent human life was lost due to line snapping. Few days ago one driver lost his life while stepping down from lorry. Till then I was searching for a solution. We all know it's just a technical issue and can be handled.
So let's discuss how to save our innocent people from electrocution ( due to line snapping or clearance issues in LT- LESS THAN 230 V PHASE TO GROUND)
My understanding is that , distribution system shall have at least 10 ohms ground resistance for pole earthing etc. So if we can earth our pole and earthwire on every 5th pole it will improve the fault current and there by blow the transformer LT fuse.
We shall have guard wires to protect line snapping issue.
So let's urge everyone to implement the standards for saving a life. We have to urge the commission to revise the cost data to save the lives.
PS: I km rabbit has resistance of .54 ohms. Means it can easily blow the fuse when phase current touches the earth wire(230/.5=460 amp, definitely 200 amp fuse will blow)
Lt line snapping- we can't lose one more life
Moderator: kunjunnips
Re: Lt line snapping- we can't lose one more life
Let's also think of having new technologies like CIRCUIT BREAKERS, Av cable in place of bear conductor, ug cable where no clearance etc.
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george.prothasis
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Re: Lt line snapping- we can't lose one more life
Regulation 73 of CEA safety, 2010 says "Every overhead line which is not being suspended from a dead bearer wire, not being covered with insulating material and not being a trolley-wire, is erected over any part of a street or other public place or in any factory or mine or on any consumer’s premises shall be protected with earth guarding for rendering the line electrically harmless in case it breaks or in any factory or mine or on any consumer’s premises shall be protected with earth guarding for rendering the line electrically harmless in case it breaks.”
Every electrical engineer is aware of the fact that to render a snapped conductor electricity harmless, we need to have a protection system which will isolate the supply from the source.
This protection system is comprising of simple kit-kat fuse unit to the most modern relay with circuit breaker and this equipment ensures the isolation of the downstream supply, in case it sensed a fault according to the pre-set value and design.
Generally, these protection system acts based on the technology and principle of
1. over current
2. earth leakage current &
3. the variation of the impedance or measurable electrical parameter of the OH line conductor.
For LT & HT, the proven technology for protection is “over current” and “earth leakage”.
Thus regulation 73 of CEA safety regulation 2010 is of greater importance in ensuring public safety in our electricity distribution system. The compliance of regulation 73 shall ensure better clarity in tripping signals and ensures the isolation of the downstream supply with far better reliability.
It is noted with great regret that we have not even considered the enforcement of the relevant provision in the mandatory CEA safety standards to ensure a better safety environment for public from our system. Over the period, we have diluted the construction standards of the distribution network and particularly, the provisions in the “system of grounding” in the CEA construction and safety standards to such an extent that the relevance of proper grounding have least importance in the distribution works….!!
Compliance of regulation 73 of CEA Safety, 2010 regulation with extra efforts to ensure a reliable system of grounding is the requirement of the day to ensure better safety to the public from our network.
Every electrical engineer is aware of the fact that to render a snapped conductor electricity harmless, we need to have a protection system which will isolate the supply from the source.
This protection system is comprising of simple kit-kat fuse unit to the most modern relay with circuit breaker and this equipment ensures the isolation of the downstream supply, in case it sensed a fault according to the pre-set value and design.
Generally, these protection system acts based on the technology and principle of
1. over current
2. earth leakage current &
3. the variation of the impedance or measurable electrical parameter of the OH line conductor.
For LT & HT, the proven technology for protection is “over current” and “earth leakage”.
Thus regulation 73 of CEA safety regulation 2010 is of greater importance in ensuring public safety in our electricity distribution system. The compliance of regulation 73 shall ensure better clarity in tripping signals and ensures the isolation of the downstream supply with far better reliability.
It is noted with great regret that we have not even considered the enforcement of the relevant provision in the mandatory CEA safety standards to ensure a better safety environment for public from our system. Over the period, we have diluted the construction standards of the distribution network and particularly, the provisions in the “system of grounding” in the CEA construction and safety standards to such an extent that the relevance of proper grounding have least importance in the distribution works….!!
Compliance of regulation 73 of CEA Safety, 2010 regulation with extra efforts to ensure a reliable system of grounding is the requirement of the day to ensure better safety to the public from our network.