Birds and Wires....

Dr Galen

Why don't birds sitting on the Luas lines get electricked?

I see them on there all the time so whats the story, aren't those lines electrifired?

Dooom

Same with them sitting on other electrical wires...bar the insulation, they're not in contact with the ground so can't earth the electricity.

aidan_walsh

Are the LUAS lines the first power lines you have ever seen? Because it would be the same reason birds don't get fried on other overhead lines.

sinjin_smythe

yeah whats the deal ? i always wanted to know but didnt want to ask the stupid question!

Dr Galen

it is widely accepted that i'm stupid so i went ahead and asked it for us all

Hail 2 Da Chimp

Its all down to a little thing called.... MAGIC!!!! Birds are magical i tells you!!!

Wertz

They don't allow the current to run to ground (ie earth) so the current doesn't and hence they don't get electrocuted...

Dr Galen

aidan_walsh wrote:

Are the LUAS lines the first power lines you have ever seen? Because it would be the same reason birds don't get fried on other overhead lines.

see i thought luas lines were different as there is that big sticky out thing on the top of the tram and the electricity comes in through that and powers the tram itself.

sinjin_smythe

ehh cormie i aint gettin a link

Hail 2 Da Chimp

Magic i tells ya..... MAGIC!!!

Basq

weedhead wrote:

ehh cormie i aint gettin a link

Try this!

Dr Galen

from the Luas to Leonard Cohen......i like it

cormie

basquille wrote:

Try this!

T'was a crap joke:p and not even a joke, just crap! Hey, how did you link it with the java and everything?

Basq

cormie wrote:

Hey, how did you link it with the java and everything?

Cos i see all...!!










... you happy enough with that answer?

sinjin_smythe

yeah funny ha ha (sarcasm) now go away !

cormie

weedhead wrote:

yeah funny ha ha (sarcasm) now go away !

Where will I go?

No Basq, I'd like a full explanation please:D

BlueSpiral

it's because they have both legs on the electric line and are not standing on earth, so the electricity can't be earthed. So the current just runs through the bird's legs, up one and down the other to the line. They don't feel anything. Simple conduction.

Hail 2 Da Chimp

BlueSpiral wrote:

it's because they have both legs on the electric line and are not standing on earth, so the electricity can't be earthed. So the current just runs through the bird's legs, up one and down the other to the line. They don't feel anything. Simple conduction.

Simple magic you mean... magic!!!

cormie

Same was as if you were to get a super soaker and fire a contstant stream of water onto a wire you'd go boom, but if you threw water balloons up, nothing would happen.

KTRIC

what if you jumped off a wall or ladder and hung onto the lines, would that be the same.


/* goes off to try it

The Doktor

it is a commonly known fact that the reason birds dont get fried, on over head wires, is because of the rubber soles on their boots.

Big Ears

BlueSpiral wrote:

it's because they have both legs on the electric line and are not standing on earth, so the electricity can't be earthed. So the current just runs through the bird's legs, up one and down the other to the line. They don't feel anything. Simple conduction.

I dunno , magic seems a little more likely than 'science'.........if that's what you call that stuff .

cormie

K-TRIC wrote:

what if you jumped off a wall or ladder and hung onto the lines, would that be the same.


/* goes off to try it

If you still had contact with either the wall or the ladder, you'd fry.

Dave

There's no potential difference between the birds and the wire. If they were to touch off another wire then they would fry.

byte

K-TRIC wrote:

what if you jumped off a wall or ladder and hung onto the lines, would that be the same.


/* goes off to try it

As long as you only touch 1 wire and you are not touching the ground you'll be fine*


*at least, that's what I heard on Tango & Cash!

Hail 2 Da Chimp

byte wrote:

*at least, that's what I heard on Tango & Cash!

Ah Tango & Cash... is there nothing they cant do???

chamlis

I'm inclined to think it's magic.

Lambsbread

K-TRIC wrote:

what if you jumped off a wall or ladder and hung onto the lines, would that be the same.


/* goes off to try it

That looks like something for Jackass!!

fly_agaric

BlueSpiral wrote:

So the current just runs through the bird's legs, up one and down the other to the line.

Nah, almost none of the current goes through the bird at all - if it did they'd be toast.:)

Merrick

Lambsbread wrote:

That looks like something for Jackass!!

Quick, someone go record him.
Post results.

jor el

BlueSpiral wrote:

it's because they have both legs on the electric line and are not standing on earth, so the electricity can't be earthed. So the current just runs through the bird's legs, up one and down the other to the line. They don't feel anything. Simple conduction.

If the bird were conducting the electricity it would go frazzle frazzle pop, and die. Electrical current only flows from a point of higher to lower potential. Since the bird is only touching one wire (and is at a single potential) then there is no current flowing anywhere in the bird.

squibs

Electrical cable is a better conductor than bird legs, and electricity will take the path of least resistance, so it doesn't flow through the bird.

BlueSpiral

jor el wrote:

If the bird were conducting the electricity it would go frazzle frazzle pop, and die. Electrical current only flows from a point of higher to lower potential. Since the bird is only touching one wire (and is at a single potential) then there is no current flowing anywhere in the bird.

Darn it

*goes back to study JC science*:rolleyes:

Electrical cable is a better conductor than bird legs, and electricity will take the path of least resistance, so it doesn't flow through the bird.

I knew that, darn it. *smacks head* what the hell is up with my brain.:/

RoundyMooney

squibs wrote:

Electrical cable is a better conductor than bird legs, and electricity will take the path of least resistance, so it doesn't flow through the bird.

Almost correct. The current flow through bird and cable will be proportional to the ratio of their respective resistances (to current flow). Since 2 inches or so of copper or aluminium/steel conducter has a far lower resistance than the same current path through feathers and tissue/bone matter, said birdie will never feel the less than .05mA current flow due to the "step voltage" present between its feet.

Bigger animals are far more susceptible, because of the distances between their legs, albeit differently. In the days before automated earthing on high tension overhead lines (10, 20 or 38,000 volts most commonly) a line falling to earth could possibly continue to conduct and dissipate a voltage gradually falling to a much lower figure in the area around the earthing point. The resulting differential voltage between a cow or sheeps front and hind legs as a result was often in excess of the (variable) level required to induce cardiac arrest and immediate death in the unfortunate animal. The result being a number of dead farm animals in the area of a downed line without any contact with the line itself...

HTH

WhiteWashMan

all of your questions regarding electricity can be answered.....


..... in the physics forum!

Panserborn

Does all this mean that if we walked barefoot along the top of an eletricified fence that we wouldn't get zotted? Assuming af course that we could keep our balance on it.

MarkoP11

Once you are not grounded you don't get fried in simple terms, path of least resistance. Now standing on a high voltage AC power line probably isn't good for you in terms its magnetic field but thats too complex

The poor little bird can get fried if by accident the bird manages to come into contact with a earth while touching the live wire. Occasionally a bird goes pop in Pearse station when its wings touch the earth wire of the overhead system while still touching one of the live wires

Just to scare you all the rails on the Luas and DART are the return conductor and in the case of the DART system can carry in excess of 2000 amps each

The earth wire is not necessarily exactly 0 volts, nor can it be assumed a live section of wire dead unless it is earthed, the latest circuit breakers used on the DART and presumably on Luas will confirm the circuit not grounded (excessive inductance) before they allow the operator to close the breaker (bird will still get fried) Only one person has been killed so far by touching the overhead wire of DART/Luas poor individual had climbed up and thus was earthed

KAGY

But have you ever seen a bird like a stork step from one phase onto the other? Me neither, but there would be a potential difference between it's legs, and it has a finite resistance so instant sunday roast, or at the least a lot of singed feathers!

Michael Collins

cormie wrote:

Same was as if you were to get a super soaker and fire a contstant stream of water onto a wire you'd go boom, but if you threw water balloons up, nothing would happen.

Or take a piss on an electric fence...Just imagine it there now...

nesf

Michael Collins wrote:

Or take a piss on an electric fence...Just imagine it there now...

They can be hard to spot if overgrown. I've heard of it happening and being described as "a shock to the kidneys". I don't really want to think about it too much tbh.

Proof that urine is conductive though, which I suppose is valuable field research in it's own way...