We have agreed on many occasions that the Table is an abomination in all sorts of senses - particularly in relation to presentation/contradictions/lacks of clarity/definitions and also the fact that the whole concept seems to be without any electrical basis - the required CSA of a conductor obviously depends upon what current it has to carry (and on installation method, ambient conditions and other factors), but why on earth does there need (electrically) be a minimum which varies according to the 'type of circuit'??In another thread EFLimpudence said:I just think the parts of Table 52.3 are so contradictory that it makes a nonsense of the contradicting parts.
It does, but you would have to ask them why they included that as a note rather than as an additional row in the table.In another thread EFLimpudence said:However, NOTE 1 states "IT, signalling and control circuits intended for electronic equipment...".
Quite so. Your guess is as good as mine.In another thread EFLimpudence said:In BS7671 there is no definition of Control Circuit but the index has for Control Circuit states "see Voltage Band 1 definition". Make of that what you will.
Since it says nothing like that, anyone who thought' as you suggest would merely be guessing. In the absence of specific definitions of what any of the individual colours 'mean', I can't see it makes much difference which are used, or in what 'order'.In another thread EFLimpudence said:As for the different identification colours in Table 51 for "Control Circuits, ELV and other applications", do people think that the colours should be used in order. That is, if only one Live conductor then Brown would be used; for more than one then in the order stated....
Fair enough.In another thread EFLimpudence said:In a central heating system where the boiler and programmer are in the kitchen and valve and tank thermostat are in the airing cupboard, one might use (as I have) a 7-core cable with numbered black conductors. Obviously the numbers are adequate but the different colours might be used for easier identification.
As has been said (in the other thread), I think that's debatable - but, as you know, I would personally not call it a control circuit if the 'controlling devices' were merely switches (including relay contacts) which were switching the full loads (of boiler and valve).In another thread EFLimpudence said:I would class that as a 230V control circuit, but it might not be what is meant.
For various reasons, I have a light switch on the ground floor which switches a light two floors above - would you call that a 'control circuit'?
Kind Regards, John