Hello, When looking at a distribution/transmission system, why are higher voltage lines more dangerous than lower voltage lines? For example when looking at a 4200 V system and a 12470 V system, the current is higher on the 4200 V system which seems like that would be more hazardous. What am I missing? Thank you in advance.
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Higher Voltage vs Lower Voltage Safety 4
- Thread starter wesles_24
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There is more chance of arc-over with higher voltages.
The higher the voltage the more chance that contact will be fatal.
That being said, the survive-ability of contact with 4200 Volts is almost the same as is contact with 12,470 Volts.
What's a four letter word to describe survival of contact with either voltage?
Bill
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"Why not the best?"
Jimmy Carter
The higher the voltage the more chance that contact will be fatal.
That being said, the survive-ability of contact with 4200 Volts is almost the same as is contact with 12,470 Volts.
What's a four letter word to describe survival of contact with either voltage?
LUCK
Bill
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"Why not the best?"
Jimmy Carter
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HamburgerHelper
Electrical
There is complacency at lower voltages that can make them equally dangerous. You'll hear stories of electricians falling over after getting shocked with 120 v and not thinking it a big deal and not seaking medical attention. 120v is scary when your hand is locked onto a live wire and you can't get your hand to let go. Anything 480v and above is like a bomb when it faults and gets treated as such.
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If you can't explain it to a six year old, you don't understand it yourself.
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If you can't explain it to a six year old, you don't understand it yourself.
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The severity of the electric shock it is a combination of the voltage level, current intensity, duration, frequency and point of contacts. The following describes a rough mechanism of electric shock and the importance of the voltage level:
• Under shock exposure over 500V, the skin may cause dielectric breakdown and
• This allows more the current to flow inside the body resulting in tissue damage and may trigger fibrillation of the heart causing cardiac arrest.
• Fibrillation is the most frequent cause of deaths in an electrical accident.
• The importance of the voltage is associated with electrothermal burns is can be explained with Joule’s law:
..>>> [highlight #FCE94F] W =R.I[sup]2[/sup].t = V.I.t = V[sup]2[/sup]/R.t[/highlight] <<<
• Statistics data indicates that shocks above 2,700 V are often fatal and the probability to survive decrease with the voltage level.
Bellow is a link describing a lucky boy that survived 230 kV shock
• Under shock exposure over 500V, the skin may cause dielectric breakdown and
• This allows more the current to flow inside the body resulting in tissue damage and may trigger fibrillation of the heart causing cardiac arrest.
• Fibrillation is the most frequent cause of deaths in an electrical accident.
• The importance of the voltage is associated with electrothermal burns is can be explained with Joule’s law:
..>>> [highlight #FCE94F] W =R.I[sup]2[/sup].t = V.I.t = V[sup]2[/sup]/R.t[/highlight] <<<
• Statistics data indicates that shocks above 2,700 V are often fatal and the probability to survive decrease with the voltage level.
Bellow is a link describing a lucky boy that survived 230 kV shock
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