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Probably a Type A downstream of an AC

Was my initial punt. We have established that, other than for some very unlikely event, (limited to 0.4 seconds max), none. so an EICR code of 2 is not applicable?

Or you could just bond the water pipes and install an RCD - or as I said , maybe green and yellow cable is your “thing”

The regs no longer require it in general because of RCD protection. Before that, or where RCd protection is not provided ,and except for in the unlikely event of a fault while you happen to be hanging on to multiple objects, I asked the question what was/is the benefit. Clearly after sp many...

What the funk is that supposed to mean ?

And I’m glad you asked that too - because other than the unlikely scenario that you happen to be in contact with an ECP, let’s say a tap, and an appliance at the exact time it creates a live/earth fault (unless that is you create the fault by touching and disturbance ), albeit for in all...

Glad I’ve got you all thinking - it’s not as cut and dried as the initial responses is it … Hmm but How/in what scenario could the fault current achieve 500 A ?

I’m cooking dinner maybe someone could do the maths. No supp bond. R1 of lights = 0.3ohm R2 of lights 0.5ohm Ze 0.2 ohm. Human of 1000ohm in contact with light fitting during live earth fault and tap. 240V supply. Main bond to water in place. What is fault current, current through human...

No I said r1 and r2 0.3 and 0.5 . I didn’t include Ze i forgot. Let me redo the math as yes you are correct 1000 and 0.5 in parallel is still just below 0.5

Good point forgot Ze. Was based on r2 of 0.5ohm r2 0.3ohm and RHuman 1000. Don’t forget human and r2 are acting in parallel so the path from the light point is 2.001 ohm. 240/2.3001=104.3A 208V because voltage drop across r1 is 32V approx and across the r2+rhuman 208V The voltage drop will...

So I’ve calculated taking the example of an exposed part of a lighting circuit that has an R1 R2 of 0.8ohms .The touch voltage at the exposed point would be approximately 208V in the event of a live earth fault before the breaker trips. Assuming a resistance as low as one thousand ohms for the...

That is what I was trying , clearly not that well, to express. Electrically no different to another cpc the further it gets away from the location , albeit significantly reducing the overall resistance of the actual cpc by being a parallel resistance . If the actual cpc is of negligible...

Sorry typo class 1 obvs

No not really , for parts that can be touched simultaneously, does the s.bond have to be made directly from the electrical item, say a class 1 light fitting or towel rail ?

Rather than focus on where on the pipe the s. bond needs to be on the pipe, how close must it be to the appliance CPC ?

Does /is supp bonding always made directly from the appliance/light fitting ?

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Thanks excellent diagram. So that contradicts what you said earlier “Since (other than in extraordinary circumstances) essentially no current will be flowing through the pipe downstream of the point of bonding, it doesn't matter where the pipe is bonded.” A-C will in practice be pretty close...

Ok so please draw the fault current flow on the diagram with the bond in place somewhere between the tap and the met

Let me put it another way for you - do you agree that the more you move that bond link nearer to the MET the less it becomes a benefit in terms of lowering any PD / Touch voltage ?