Electric shock treatment

[ColJack]

proof posisive that volts don't kill..

http://youtube.com/watch?v=9tzga6qAaBA&feature=related

Volts is potential difference, current is the flow of electrons through a conductor.

 

[ban-all-sheds]

11Kv does not kill the birds that perch on the un-insulated cables of a over head cable..

FGS.

That's because if they are perched on one cable they are not experiencing 11kV.

Do you understand anything about what "voltage", or "potential difference" is?

 

[ban-all-sheds]

proof posisive that volts don't kill..

Proof positive that you don't understand it either.

Volts is potential difference, current is the flow of electrons through a conductor.

And with no potential difference, no current flows.

Voltage creates the current.

Your argument is akin to "Being shot doesn't kill you, its the loss of blood and damage to internal organs that kills you".

 

[tim west]

be careful when quoting PD and voltage so freely, It is just a potential until referenced to a different potential does it then become a potential difference or voltage that can produce a current flow in a circuit.

 

[bernardgreen]

Do you understand anything about what "voltage", or "potential difference" is?

I hope so......I have been working in electronic and production machinery design for 40 years and part of that was the risk assesment of the electrical ( and mechanical ) risks of the equipment being designed.

There is danger to life from a potential difference only if it can cause a current to flow through the body.

On the video the arcing between cable and helicopter is the current required to bring the helicopter to the voltage of the line to ensure the person moving from helicopter to cable does not bridge a potential difference. The arc is continuous as the AC voltage requires helicoptor to be charged positv then negative 50 times second.

There is a clip on cable linking the helicopter to the cable during the transfer. This is necessary as at 132 Kv there will a substantial current flowing into the air from all pointed parts of the helicopter ( known as electric wind that flows from pointed objects when charged to high voltage ).

The person wears a Faraday cage coat as the electric wind from the tools being used would result in a current flowing through his body if the tool was not connected to the cable by a metallic path.

The most common task is checking the bolts at the base of the insulator

 

[tim west]

As anyone who has experienced a van der graff generator, one can touch a very high potential and actually be charged by it, humans make a great reservoir for charge the danger comes if someone gets too close and discharges you, it dont half hurt!

 

[Softus]

Do you understand anything about what "voltage", or "potential difference" is?

I hope so......I have been working in electronic and production machinery design for 40 years and part of that was the risk assesment of the electrical ( and mechanical ) risks of the equipment being designed.

I'm sure you do understand, bg, but you're using the wrong words. Semantics it might well be, but being precise is often important. Hence...

There is danger to life from a potential difference only if it can cause a current to flow through the body.

Any P.D. (aka 'voltage') across a body will cause a current to flow through that body. If the P.D. is high enough, and/or the body's resistance is low enough, then the current flowing will be high enough to be dangerous.

 

[tim west]

Sorry softus to contradict you but you can connect a low resistance to a votage potential but no current will flow unless there is some form of return path or a circuit. And bernard stated that.

 

[Softus]

...you can connect a low resistance to a votage potential but no current will flow unless there is some form of return path or a circuit.

That's a contradiction in terms - if you have a potential difference between two points then by definition those two points are part of the same circuit.

If you doubt the accuracy of the words then consider the following scenario that I've based on your words:

1. Connect a single conductor to one pole of a SP switch, and bare the end.

2. Connect another conductor to the other pole, and the other end of that to your MET.

3. Remove the cover from your CCU.

4. Open the SP switch.

5. Measure the PD between the CCU live incomer and the bare-ended conductor. This should be zero volts.

6. Wearing rubber-soled shoes, and standing on a rubber mat, and holding the end of the bare-ended conductor, grasp the CCU live incomer terminal.

7. Since you're still alive and unscathed, let go of the CCU terminal. Wipe the sweat of your temples, and change your underpants.

8. Close the SP switch, and repeat step 5. This measurement should now be circa 240 volts.

9. Tell your wife where to find your will, and prepare to repeat step 6.

 

[tim west]

...you can connect a low resistance to a votage potential but no current will flow unless there is some form of return path or a circuit.

That's a contradiction in terms - if you have a potential difference between two points then by definition those two points are part of the same circuit.

You are misquoting me then as i didnt say potential difference i said voltage potential, two distinct things, as it's still just about current(topically that is) lets take a set of christmas tree lights, if you only connect one end of the set to the mains live terminal and leave the other end floating then the bare unconnected end will be at mains potential as will any point along the set it's only when connected to the neutral terminal that there is current flow and then a potential difference across each lamp, depending on the amount of lamps this potential difference drops down to 6 or 12 volts. The birds on the power line are in a similar series connection to gnd except for one big factor the air that connects them to gnd is of such high resistance(plus the body resistance as though that made any difference!) that the potential difference is virtually non existant or so low that current cannot flow through the circuit, therfore it can be termed as "open circuit" in other words the birds are disconnected from any circuit but are still at a high potential.

If you were to measure with a meter thats capable of measuring such high voltages then tested between the birds and gnd you would then be shorting out the air insulator or high resistance and create a return path and read a pd and the birds wouldnt be too happy.

 

[securespark]

How d'you know they're friends?

 

[tim west]

How d'you know they're friends?

Should that be in the "wrong thread" thread? dont get your meaning

 

[securespark]

In relation to the birds on the wire...

 

[tim west]

Go on (i know i'm gonna regret this ) whats the relationship?

 

[Softus]

You are misquoting me then as i didnt say potential difference

That's a bunch of horsesh*t - I only replied to you because you said you were contradicting me.

You disagreed with the correction I posted to bernardgreen's words, which were:

There is danger to life from a potential difference only if it can cause a current to flow through the body.

If you're claiming that "votage potential" (sic.) is different, then did you agree with my usage of the words "potential difference"? If so then my post contained no errors and there was no need for you to bother posting at all.