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Grid switch ratings enquiry

Farmboy
Had an interesting chat with a tech dept this afternoon after coming across some grid switches in a domestic kitchen.


Four grid switches (sharing a common backbox) are each fed via their own 16A cb's, and each feeds 1G sockets (for a cooker hood, fridge freezer, etc). Ignoring the cable sizes (the focus being on the grid switches), given the 13A plug fuses limits the loads in each cct, would you have the current rating of the grid switches equal to or higher than the 16A cb's (e.g. 20A), or lower (but equal to or higher than the socket rating e.g. 13A/14A)?


F
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    Had an interesting chat with a tech dept this afternoon



    Ah, this is going to be something "interesting" then - possibly something to do with the new regulations about co-ordinating switches etc with overcurrent protection (e.g. 536.4.2.3). Seemingly we can't just assume that a 20A switch is going to behave like a bit of 20A cable as far as faults are concerned (like we probably used to) - but we need the switch manufacturer's data in order to select fault protection - so I'm guessing that they've said something like a 20A MCB can't protect a 16A switch even if there's overload protection further downstream.


      - Andy.
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    Had an interesting chat with a tech dept this afternoon



    Ah, this is going to be something "interesting" then - possibly something to do with the new regulations about co-ordinating switches etc with overcurrent protection (e.g. 536.4.2.3). Seemingly we can't just assume that a 20A switch is going to behave like a bit of 20A cable as far as faults are concerned (like we probably used to) - but we need the switch manufacturer's data in order to select fault protection - so I'm guessing that they've said something like a 20A MCB can't protect a 16A switch even if there's overload protection further downstream.


      - Andy.
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