Hi all
For those who are regular posters in the group, you may remember a saga relating to diversity and a building control inspector who has decided -that this may not be applied to a cooker circuit (see The Inspector Calls - Part P 17-03-2011)
Many regulars here responded with chapter and verse on this, providing links to articles and quoting the relevant clauses of BS7671. These were all forwarded to the inspector along with a quotation from the IET themselves supporting this approach. Most importantly I must acknowledge the technical help and moral support from Adam Wadsworth and John Rumm in attempting to resolve the issue with me.
Not only did the inspector himself refute the regulations, but his boss (the manager of building control) was also apparently prepared to do the same.
The problem for my project was that, without considering diversity, the appliances that could be supplied from what is a pretty standard 32A cooker circuit would be severely limited.
Emails were exchanged over about 2 weeks on the subject, with responses including the text below:
After speaking with Mr (manager of Building Control ), the Council's opinion is that you need to use the potential full load of the two appliances that you are installing when calculating the cable size as it has the potential during certain times that both appliances could be running at maximum load or very close and the applying of the first 10amp and 30% of remainder is not suitable in this case as it would under size the cable (as per previous e-mail), and we are not interested in any further debate regarding this.
A few emails later and an official-sounding message was received threatening such things as formal enforcement, £5000 fine and (most importantly IMO) an entry in the land charge register.
By this point, I was spending far more time researching and concocting emails than actually getting on with the job in hand. I do feel I owe an apology to many members of the group in not seeing this through to the correct conclusion, but feel that my tether's end had certainly been reached on the subject. So I offered the council a "solution" to this issue - to engage a Part P certified electrician to design, install and certify the cooker circuit (I would retain responsibility for kitchen ring main and lighting). This gets the job done to my satisfaction, but does allow the council to walk away from the situation effectively uncorrected.
Having tried to complete this project "the right way" I can now fully appreciate why other posters have advised avoiding council involvement at all costs.
Phil