Why dont birds get electrocuted when sitting on bare power lines?

[JEDI]

if a human touched bare high voltage power lines, they'll be dead + very crispy. but birds are unaffected.

Why?

 

[Throckmorton]

Because the power goes through the line, not the bird. The wire is an easier route for the current than the bird. A human can hang on a line the same way. If you touch two lines, then the current goes through you because it's easier than going a few extra miles to transformers or whatever.

 

[2Xtreme21]

The wire provides lower resistance than the bird. If a human touches the wire, he/she would provide the easiest path to the ground.

 

[minendo]

Not grounded.

 

[AMCRambler]

One reason. If youre not grounded youre not dead.

 

[91TTZ]

I can't believe that nearly everyone who replied so far lacks even a basic understanding of electricity.

Minendo, AMCRambler, good job.

Touching the line will raise the charge in you to the line's potential, but it cannot flow anywhere else because you're not grounded. If you were to hang on the line or work on it with a helicopter you'd be ok. If you dropped a conductive cable to the ground you'd get fried.

 

[PowerEngineer]

Not exactly true. If a human can manage to perch on a single conductor as a bird does, then he/she will also be unharmed. What kills you (or the bird) is when your body provides electricity with a path between points having different voltages. In other words, if you touch a bare conductor (distribution lines are commonly 13 kV) with your feet planted on terra firma (~0 kV) then you'll have current flow through your body that will turn you "crispy". It also happens to birds, squirrels, and other small animals as they fly or climb around wires and substations; their fatal mistakes are a pretty common cause of distribution outages.

 

[marvdmartian]

Yeah, snakes commonly cause outages, as they stretch across from one line to the next one. Saw it all the time when I lived in Guam, with those damn brown tree snakes (who obviously couldn't tell the difference between a tree and a damn power pole!).

 

[frostedflakes]

Yup, it's all about grounding. I remember my physics teacher in HS touching a live 120V wire. He was wearing thick rubber boots. No path to ground = no electrocution.

 

[WHAMPOM]

Originally posted by: JEDI
if a human touched bare high voltage power lines, they'll be dead + very crispy. but birds are unaffected.

Why?

Tell that to all the dead eagles that touch two wires. And the live linemen in their insulated cherry pickers.

 

[MrPickins]

It's been posted here before, but this is awesome:

"Like a Bird on a Wire"

Slightly better quality:
http://www.youtube.com/watch?v=HcalasGr_uk&FMT=18

 

[Gothgar]

Originally posted by: minendo
Not grounded.

 

[PowerEngineer]

Originally posted by: MrPickins
It's been posted here before, but this is awesome:

"Like a Bird on a Wire"

Slightly better quality:
http://www.youtube.com/watch?v=HcalasGr_uk&FMT=18

Note that on really high voltage lines (like the ones shown in the video), it's very common to string two or more conductors on each phase (rather than one bigger conductor). The two conductors he's working on are actually the same voltage, which is why he can touch both at the same time.

Also note how they use a small rod to initially touch the conductor as the helicopter nears the line. This allows the conductor to charge the helicopter up to its voltage (and then stay with it through the 60 Hz cycle).

 

[imported_Baloo]

Originally posted by: 2Xtreme21
The wire provides lower resistance than the bird. If a human touches the wire [while in contact with a ground source], he/she would provide the easiest path to the ground.

fixed

 

[Special K]

Originally posted by: Gothgar

Originally posted by: minendo
Not grounded.

Yup.

 

[her209]

Originally posted by: PowerEngineer

Originally posted by: MrPickins
It's been posted here before, but this is awesome:

"Like a Bird on a Wire"

Slightly better quality:
http://www.youtube.com/watch?v=HcalasGr_uk&FMT=18

Note that on really high voltage lines (like the ones shown in the video), it's very common to string two or more conductors on each phase (rather than one bigger conductor). The two conductors he's working on are actually the same voltage, which is why he can touch both at the same time.

Also note how they use a small rod to initially touch the conductor as the helicopter nears the line. This allows the conductor to charge the helicopter up to its voltage (and then stay with it through the 60 Hz cycle).

What are you? Some kind of Electrical Engineer?

 

[BrownTown]

Like 20 other people have said, electricty needs a complete path to flow, if you are only touching one wire then the circuit is incomplete. When my dad started wotk at TVA part of the training was everyone had to touch one of the 161kV lines from one of the insulated cherry pickers.

 

[Fraggable]

Originally posted by: her209

Originally posted by: PowerEngineer

Originally posted by: MrPickins
It's been posted here before, but this is awesome:

"Like a Bird on a Wire"

Slightly better quality:
http://www.youtube.com/watch?v=HcalasGr_uk&FMT=18

Note that on really high voltage lines (like the ones shown in the video), it's very common to string two or more conductors on each phase (rather than one bigger conductor). The two conductors he's working on are actually the same voltage, which is why he can touch both at the same time.

Also note how they use a small rod to initially touch the conductor as the helicopter nears the line. This allows the conductor to charge the helicopter up to its voltage (and then stay with it through the 60 Hz cycle).

What are you? Some kind of Electrical Engineer?

While he explained it very well, the knowledge he showed there should really be common knowledge for anyone interested in not being shocked. It's a good idea to understand how electricity works... grounding... current flow...

 

[potato28]

Not grounded.

 

[JohnCU]

the transmission guys at work do bare handed work on 230kV all the time.

 

[91TTZ]

Originally posted by: Fraggable

Originally posted by: her209

Originally posted by: PowerEngineer

Originally posted by: MrPickins
It's been posted here before, but this is awesome:

"Like a Bird on a Wire"

Slightly better quality:
http://www.youtube.com/watch?v=HcalasGr_uk&FMT=18

Note that on really high voltage lines (like the ones shown in the video), it's very common to string two or more conductors on each phase (rather than one bigger conductor). The two conductors he's working on are actually the same voltage, which is why he can touch both at the same time.

Also note how they use a small rod to initially touch the conductor as the helicopter nears the line. This allows the conductor to charge the helicopter up to its voltage (and then stay with it through the 60 Hz cycle).

What are you? Some kind of Electrical Engineer?

While he explained it very well, the knowledge he showed there should really be common knowledge for anyone interested in not being shocked. It's a good idea to understand how electricity works... grounding... current flow...

QFT.

My dad taught me this when I was about 10.

 

[FlashG]

Like others have said, if there is no path to ground all potentials are the same and there is no problem. If one bird pecked the feet of another bird resting on a different conductor you have to make a desision. Regular or Extra Crispy?

 

[0roo0roo]

Originally posted by: 91TTZ

Originally posted by: Fraggable

Originally posted by: her209

Originally posted by: PowerEngineer

Originally posted by: MrPickins
It's been posted here before, but this is awesome:

"Like a Bird on a Wire"

Slightly better quality:
http://www.youtube.com/watch?v=HcalasGr_uk&FMT=18

Note that on really high voltage lines (like the ones shown in the video), it's very common to string two or more conductors on each phase (rather than one bigger conductor). The two conductors he's working on are actually the same voltage, which is why he can touch both at the same time.

Also note how they use a small rod to initially touch the conductor as the helicopter nears the line. This allows the conductor to charge the helicopter up to its voltage (and then stay with it through the 60 Hz cycle).

What are you? Some kind of Electrical Engineer?

While he explained it very well, the knowledge he showed there should really be common knowledge for anyone interested in not being shocked. It's a good idea to understand how electricity works... grounding... current flow...

QFT.

My dad taught me this when I was about 10.

think i saw that on modern marvels or whatever. freaky stuff. get too close to the tower and it'll jump the last couple feet and zap u

 

[skyking]

Originally posted by: her209

Originally posted by: PowerEngineer

Originally posted by: MrPickins
It's been posted here before, but this is awesome:

"Like a Bird on a Wire"

Slightly better quality:
http://www.youtube.com/watch?v=HcalasGr_uk&FMT=18

Note that on really high voltage lines (like the ones shown in the video), it's very common to string two or more conductors on each phase (rather than one bigger conductor). The two conductors he's working on are actually the same voltage, which is why he can touch both at the same time.

Also note how they use a small rod to initially touch the conductor as the helicopter nears the line. This allows the conductor to charge the helicopter up to its voltage (and then stay with it through the 60 Hz cycle).

What are you? Some kind of Electrical Engineer?

QFSMC

 

[lightstar]

at the bottom of the bird's talon are michelin-like rubber pads that protect them against electrocution