Probably being a bit pedantic, but I have usually connected range hoods via a socket outlet at least 2.3m high onto a 1mm lighting point, but on reading the maximum demand notes in Appendix C realise this may no longer a practical option. Note "f" on Table C8 allows a socket outlet on a 1mm as long as its 2.3m high and the appliance is less than 150w. Most newer hoods are just a bit over this at around 190w. In some cases I don't even know which hood model will be fitted after I leave.
Question1: The cable is protected via the MCB rating so cannot see a safety issue arising and the socket is behind the hood cowling at 2.3m off the floor so cannot be used for general purposes. Table C8 is headed as "Guidance on the loading of points per final sub circuit", so can we still use discretion and fit a 200w hood to a lighting point?
Question2: If Table C8 is mandatory, assuming we select a matching CCC for the cable, is a jump off the oven socket permitted for the hood?
Rangehoods and Max Demand
Re: Rangehoods and Max Demand
Table C8 - in fact all of App C is guidance, not requirements (indicated by the word "informative" rather than "normative" at start of Appendix).
So provided the 1.0 mm2 is protected for overcurrent, no compliance issue.
But if you take it from the range circuit; you've got a reduction in CCC that by default requires an additional overcurrent device (ie additional to the one at origin of subcircuit), unless you can take advantage of an exception to 2.5.1.2
eg the entire subcircuit is downgraded to match the CCC of the 1.0 mm2.
If you do that, best to place a clear Note explaining at the swbd; to avoid someone coming along later and thinking they can up-rate the circuit protection because they don't know why it's so low compared with the big cable leaving the swbd.
Or use a PCU instead of a socket.
So provided the 1.0 mm2 is protected for overcurrent, no compliance issue.
But if you take it from the range circuit; you've got a reduction in CCC that by default requires an additional overcurrent device (ie additional to the one at origin of subcircuit), unless you can take advantage of an exception to 2.5.1.2
eg the entire subcircuit is downgraded to match the CCC of the 1.0 mm2.
If you do that, best to place a clear Note explaining at the swbd; to avoid someone coming along later and thinking they can up-rate the circuit protection because they don't know why it's so low compared with the big cable leaving the swbd.
Or use a PCU instead of a socket.
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Re: Rangehoods and Max Demand
"informative" vs "normative", subtle distinction to look out for in future 
. Thanks.
. Thanks.Re: Rangehoods and Max Demand
Explained in the Foreword, along with several other important aspects.
Standards are written to a carefully-designed structure, so learning the way they're put together helps us arrive at the intended meaning.
Standards are written to a carefully-designed structure, so learning the way they're put together helps us arrive at the intended meaning.