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V= IR P = (I x I)R Do the maths!

John, An increase in heat must be caused by an increase in power, therefore the resistance must be less. Otherwise you are telling me that to make something hotter takes less energy, which obviously makes no sense.

John, If the cpc is getting hot, it is using power to do it!

Therefore Chapter 41 is in its' entirety concerned with the speed of automatic disconnection. If the speed of automatic disconnection cannot be met by over-current protective devices alone, the touch voltage or potential difference between two earthed conductors will rapidly be increasing as...

Table 41C offers us an alternative way of meeting our disconnection times only it gives us R2 values as opposed to loop impedance values, this is a part of the discussion over Table 41C. If you meet the R2 values within Table 41C this will give a disconnection time of 0.4seconds, because you...

echoes/John, The loop impedance values given within Chapter 41 are unlikely to be met in a TT system, hence the use of an RCD or local supplementary bonding.

echoes, Ohms law is the basis of prospective fault current and loop impedance.

John, The equation above proves that the more power you use, the more current you must use; and you need to use power to heat the cpc!

The current has to increase to a point where the speed of automatic disconnection of supply is met.

echoes, You are being asked to believe that during a fault of negligable impedance to earth the temperature of a cpc increases, but during this time the resistance of the cpc is increasing as the current flow is also increasing. Which contradicts ohms law!

holmslaw, Do you understand 'ohms law' as it is being used above?

ebee, Do I need to do the maths for you? V = IR therefore: 240v = 60amps x 4ohms or; 240v = 120amps x 2ohms. Therefore P = (I x I)R (60 x 60) x 4 = 14400watts or; (120 x 120) x 2 = 28800watts. The resistance is lower therefore the current increases along with the power!

Every Electrician that I have met agrees with every word I say.

Spatikus, You asked for a debate, suddenly the quality of your answers has gone down hill rather rapidly. Try touching an energised line circuit conductor as I did, then debate me once you've grown up a bit.

Hi Martin, No I haven't done any book signings, it isn't even finished yet in truth. The only reason I wrote it was because I had no choice, I am still waiting for 25 e-mail replies from the IET. The BSI, the ESC, the ECA, the HSE and various other can't answer any of the questions I've...

DIYers yes please beware, touching a live circuit conductor is a very painful experience and will be so even when you are stood on floorboards! Take it from someone who has had first hand experience, don't listen to people who 'theorize' that you can't hurt yourself because it isn't true!

Bernard, I ramp tested the RCD to make sure it was operating at 30mA, then I deliberately touched the line circuit conductor to prove to myself that although less than 30mA flowed, the shock was still of a magnitude great enough to kill. If the duration of the shock had been extended, I can...

Interesting thought Martin.

Spartikus, As a responsible adult (let alone a responsible electrician) you must prove that it can't happen.

Mathematically - there is damp in the atmosphere, if you are close enough to the mass of the earth the damp will connect your feet to the mass of the earth. Why does lightning move across the sky in humid weather? I can't say for certain I'm an electrician not a scientist, but I know pain...