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Electric cooker switches

Arran Cameron
I hope that this doesn't come across as a daft question...


Why do most electric cooker switches have an in-built socket? Do analogous cooker switches exist in other countries that use different types of mains sockets?


I used to think that the socket was for plugging in a gas cooker electric ignition, but there is no real reason for having a separate circuit from the ring main for this.
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    Andrew Jewsbury:


    Highly unlikely - just look at the curves for BS 3036 fuses. - a 30A fuse may well carry over 50A for a couple of hours before opening - even if the fusewire was already warm, a few minutes it takes to boil a kettle isn't going worry it (similar for the thermal element of MCBs). The old 100% of the first 10A, 30% of the remainder + 5A for a socket rule has proved it worth for probably many millions of Christmas dinners over the best part of a century - even during the times when my grandmother's generation would boil veg for 20mins at full boil with no lid.

    I am well aware that fuse wire is conservatively rated so is capable of carrying 150% of its quoted current for over an hour before melting through. However, the apocryphal story doesn't provide any figures for the current consumption of both the cooker and the kettle. It's not unknown for large cooking appliances to be protected with a 30A fuse that really warrant 45A. Users can often get away with 30A during day to day use, but if every element is on full blast and another appliance is plugged into the socket then it's possible that the combined current will be sufficient to blow a 30A fuse.
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  • 0

    Andrew Jewsbury:


    Highly unlikely - just look at the curves for BS 3036 fuses. - a 30A fuse may well carry over 50A for a couple of hours before opening - even if the fusewire was already warm, a few minutes it takes to boil a kettle isn't going worry it (similar for the thermal element of MCBs). The old 100% of the first 10A, 30% of the remainder + 5A for a socket rule has proved it worth for probably many millions of Christmas dinners over the best part of a century - even during the times when my grandmother's generation would boil veg for 20mins at full boil with no lid.

    I am well aware that fuse wire is conservatively rated so is capable of carrying 150% of its quoted current for over an hour before melting through. However, the apocryphal story doesn't provide any figures for the current consumption of both the cooker and the kettle. It's not unknown for large cooking appliances to be protected with a 30A fuse that really warrant 45A. Users can often get away with 30A during day to day use, but if every element is on full blast and another appliance is plugged into the socket then it's possible that the combined current will be sufficient to blow a 30A fuse.
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