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to throw the cat into the pigeon coop........ so we are believing that a , say, 0.4 sec. disconnection time cannot be achieved if the Zs of a circuit is a fraction of an ohm above the BS7671 ( corrected, Cmin etc.). who's to say if this is dangerous, or potentially dangerous? how can anyone assume that a person in contact with a "live" exposed part and an extraneous part cannot endure a touch voltage of <50V for a split second longer without dying? have the IET done some tasting on animals to prove or disprove? or is it a case of "let's make something up to justify new regs./amendments?
 
Why was this Cmin not come to light years ago it must have always been something to take into account.
You know what will happen next, although in the table it gives maximum Zs values they will write a new reg that states any new circuit must be designed to a max percentage of that to give allowances.
 
to throw the cat into the pigeon coop........ so we are believing that a , say, 0.4 sec. disconnection time cannot be achieved if the Zs of a circuit is a fraction of an ohm above the BS7671 ( corrected, Cmin etc.). who's to say if this is dangerous, or potentially dangerous? how can anyone assume that a person in contact with a "live" exposed part and an extraneous part cannot endure a touch voltage of <50V for a split second longer without dying? have the IET done some tasting on animals to prove or disprove? or is it a case of "let's make something up to justify new regs./amendments?
Not sure you can write that on your report tho :)
If you can’t guarantee the disconnection times quoted by the regulations by using the generic time curves or the manufacturers data for their OCPD’s then you can’t fully comply with the regulations regarding fault protection.
 
I'm not going to argue with anyone who advocates a code 2. That's an interpretation which can be justified. But my interpretation is that a compliant circuit is not safe one day and potentially dangerous the next simply because some boff playing with figures moves the goalposts to justify his existence.
However as already stated I will discuss the issue with my NICEIC inspector on his next visit and if he thinks a code 2 is appropriate then that's what I'll do in future...…(through gritted teeth mind you)
 
I'm not going to argue with anyone who advocates a code 2. That's an interpretation which can be justified. But my interpretation is that a compliant circuit is not safe one day and potentially dangerous the next simply because some boff playing with figures moves the goalposts to justify his existence.
However as already stated I will discuss the issue with my NICEIC inspector on his next visit and if he thinks a code 2 is appropriate then that's what I'll do in future...…(through gritted teeth mind you)
Keep us updated if you don’t mind if your inspection is anytime soon?
Would be interested to hear another opinion on it
 
Mmm, wonder what this opinion will be:)
 
For me it's C2 on a report (sorry). Getting very imaginative - the "fix" could be a temperature and load study proving headroom in the 80% factor, but only in a managed installation. This would then be written onto EIC as a deviation.
 
to throw the cat into the pigeon coop........ so we are believing that a , say, 0.4 sec. disconnection time cannot be achieved if the Zs of a circuit is a fraction of an ohm above the BS7671 ( corrected, Cmin etc.). who's to say if this is dangerous, or potentially dangerous? how can anyone assume that a person in contact with a "live" exposed part and an extraneous part cannot endure a touch voltage of <50V for a split second longer without dying? have the IET done some tasting on animals to prove or disprove? or is it a case of "let's make something up to justify new regs./amendments?
I did some tasting on a couple of animals last night. I had a chicken and lamb curry, it was delicious.:D
 
I have bowed to the inevitable and issued the EICR with a code 2 for the high Zs. While I still do not agree I've no doubt the NIC will say a code 2 and that seems to be the majority view on here. Remedial will only involve changing a type C for a B, which will no doubt prompt comments about why bother making a fuss. Well I like coding to be correct and justified on my reports regardless of the cost of rectification.
 
I think you are taking the correct action in both cases, code 2 for the New World Order, and feeling that you do not agree but want to get things correct and justified.
The risk assessment would say
Hazard: long disconnection time
Likelihood: 0.0001%, low 1,
Effect: death, high 5.
Risk assessment overall 5, low risk, no action to take, no control measures required.
Overruled by IET random thoughts.
Full control measures to be implemented.
 
I'm not going to argue with anyone who advocates a code 2. That's an interpretation which can be justified. But my interpretation is that a compliant circuit is not safe one day and potentially dangerous the next simply because some boff playing with figures moves the goalposts to justify his existence.
However as already stated I will discuss the issue with my NICEIC inspector on his next visit and if he thinks a code 2 is appropriate then that's what I'll do in future...…(through gritted teeth mind you)

Why don’t you stick by your guns if you are so certain? What is it about your NICEIC Inspector that you respect so much?

If I was certain of ny stance I would be telling the NICEIC what I am doing not asking them if I can.
 
Mostly because inconsistencies in coding is an issue for recipients of EICR's. I think consensus and following established guidelines is important for an EICR to be credible, the worst EICR's I have seen are where the inspector has applied his own prejudices. I recall one where neutrals in a switch box had been given a code 2.
 

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