As others have said, I really think you are worrying unnecessarily. It takes a lot more than 60A, flowing for a very appreciable period of time to cause a 60A fuse to blow (e.g. 100A would probably take well over half an hour to blow the fuse). Countless households have all the things you mention, plus a lot more (tumble dryers, ovens, hobs, microwave, fan heaters, toasters etc. etc.) many of which may occasionally be on simultaneously, but it's very rare for such 'overloads' to result in blowing of a 60A or 80A service fuse.That's a risk I'd rather not take. Occasionally the washing machine, bathroom heater and kettle are on simultaneously. Combined with a shower unit and background consumption the total load would be more or less 60 amps.
They are very conservative. By virtue of the the operating characteristics of MCBs and cartridge fuses, cables are deemed to be able to safely carry at least 1.45 times their rated values for 1 hour - e.g. 16mm² with installation method C is deemed to be able to carry at least 123A (85A x 1.45). However, as often discussed, here, even that figure is undoubtedly very conservative.Concerned more about the 16 mm² distribution cable taking >60 amps than the blowing the supply fuse (which I'd also rather not do). It is precisely the fact that the 60 A BS 1361 fuse requires about 100 amps (99th percentile or whatever) over an hour before blowing which makes the matter of overloading the distribution cable a risk I'd rather avoid. Just how conservative are the ampacity figures for these cables? Will a 16mm² T&E safely carry, say, 80 amps for twenty minutes?
Indeed. However, as you will have seen, although the concern the OP initially expressed was that he might 'overload' the cut-out fuse, he is now worrying because it might not operate if he overloads it, and is therefore now worrying about the cables. I'm sure that we can all agree that he is in no different a position from most other UK householders and is worrying totally unnecessarily.Cut-out fuse will carry a 47% overload prety much indefinately. ... We very rarely get called out to a blown cut-out fuse in these conditions, apart from the inconveniance the DNO will replace the fuse FOC anyway, usually within 3 hours during the day
Indeed, and you would have even more leeway than that for half an hour.That 45% extra capacity is more than sufficient to cover the potential overload.
You're welcome.Thanks to each of you for the helpful and informative replies.
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