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Appliance Ratings and 13A plug tops

statter
Hello

I looked last year for portable heating and not surprisingly there was little above 2.5kW rating.  All the old 3kW stuff has long gone.

I was surprised however to find a wide range of steam irons rated at 3000W and even 3100W.  (that's almost 13.5A at 230V).  I realise of course that irons are likely to be much more intermittent than heating and that 13.5A is very unlikely to blow a 13A fuse but it cant be good practice to overload plug/ socket like this.  A decent ironing session can still be hours ……   OFC at 240v its under 13A but 230v has been the standard for ages now.   In my experience many socket/ plug combinations are marginal approaching their rating so deliberate overloading will only make matters worse over time.  I would have thought that these appliances wouldn't qualify for CE marking and couldn't be sold legally?  Does anyone know if there is a BS or EN for small appliances?


Thanks


Peter
  • 0
    I cringe when I hear or see plugtops, they are 13A plugs, likewise when some call current - juice. I remember in the 60's when electricity shops were in almost every town; they would recommend withdrawing and inserting plugs at intervals, to clean the contact, surface area when there were complaints of plugs over heating. I have seen 2 instances recently where 13A plugs and their marrying sockets were charred. when on wall heaters. I suspect it is the specification that's in error, where the UK is a test bed but there is little feedback.


    Jaymack. .
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    broadgage:

    There is a general acceptance that 13 amp plugs and sockets can not reliably and continually carry more than about 10 amps. Therefore domestic appliances are in practice limited to about 10 amps, presumably to avoid warranty claims about melted plugs.

    The main exception is electric kettles, these are used so briefly that a full 13 amps is fine. Table top electric cookers are sometimes a full 13 amps, under worst case conditions, but much less most of the time and again are fine in practice.


    Large steam clothes irons are not common domestically, but should also be fine as continual full load operation is unlikely. I have seen steam irons in a tailors workshop that require two 13 amp supplies. One for the iron itself, actual loading about 5 amps, and a second supply for the remote steam generator, actual loading about 12 amps. Often both plugged into the same socket with a death cube.


    Domestic appliances likely to run continually are unlikely to exceed 10 amps these days.


    3Kw heaters are still available but are marketed as being for industrial use and are therefore supplied without a plug. No warranty claims about melted plugs if plug not supplied. 




    I'm sure the thinking is not quite along those lines.


    The thing that has changed is that, quite a number of years ago now, the rating of a double socket-outlet has been 13 A, whereas it used to be 20 A.

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    dearth of 3kW space heaters



    There's also the issue that some European countries have a lot of 10A sockets still in use - so if you're designing a single product for the international market you've got to work within the lowest common denominator.

       - Andy.
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    gkenyon:




    statter:

     I suspect that the dearth of 3kW space heaters is because the plugs are problematic at 230V whilst even the latest steam generating irons have duty cycles that are low enough to get away with it.  




    It's really probably energy efficiency - oil-filled and halogen devices are cheaper to run than a 3-bar fire or the "snail fan and coil" type heaters.


    All electrical heaters are 100% efficient. If it uses a kW of electricity it gives out a kW of heat whether it is an oil filled radiator, fan heater or bar fire.


     




     

  • 0

    All electrical heaters are 100% efficient.



    Only when viewed in the narrow context of electricity in vs heat out. Looking at the wider context (say power station fuel in, to comfort levels achieved) it may appear somewhat less favourable. Just look at the latest efficiency standards for things like storage heaters (Lot20) -  which try to ensure that no more heat is produced than is actually needed - from better thermostats to 'open window' detection to the ability to turn them off if you're unexpectedly away from home - so using less electricity to achieve the same comfort level.

       - Andy.
  • 0

    AJJewsbury:




    All electrical heaters are 100% efficient.



    Just look at the latest efficiency standards for things like storage heaters (Lot20) -  which try to ensure that no more heat is produced than is actually needed - from better thermostats to 'open window' detection to the ability to turn them off if you're unexpectedly away from home - so using less electricity to achieve the same comfort level.

       - Andy.

    That is not efficiency though is it? It is another example of the wrong use of language like plugtop.




     

  • 0

    GeorgeCooke:




    gkenyon:




    statter:

     I suspect that the dearth of 3kW space heaters is because the plugs are problematic at 230V whilst even the latest steam generating irons have duty cycles that are low enough to get away with it.  




    It's really probably energy efficiency - oil-filled and halogen devices are cheaper to run than a 3-bar fire or the "snail fan and coil" type heaters.


    All electrical heaters are 100% efficient. If it uses a kW of electricity it gives out a kW of heat whether it is an oil filled radiator, fan heater or bar fire.

     


     




    That may be the case, but assumes that none of the heat is wasted at any point in the process, and ignores thermal constants.

  • 0
    I am surprised that idea that electricity makes things very efficient is coming out here. Overall the efficiency is somewhere in the 30-40% bracket if the WHOLE cycle is taken into account. There is a curious idea coming from some that electricity is 100% efficient, free and unlimited. Even if your use is a heater, consider the power station, grid, transformers, LV network, and even the light it may give out. the noise from the fan etc. You may say that it is solar, but the panels are still 30% or less, the inverter maybe 95% or less depending on the power, manufacturing the panels, installing and transport from China etc. Are they still free electricity? No.


    Whatever we do there is a large energy cost in getting sunlight (fossil fuels, solar, wind) to an energy form we can use. Sensible economics says all these should be considered and costed. Have you noticed the way in which this is avoided by everyone from Government to consumer?


    The only 13A plugs which I have seen which carry 13A or more without difficulty was the MK safetyplug, which was eliminated years ago because it cost more than other makes. It had big terminals, silver plated fuse holder and very strong palstic moldings. Time passes...
  • 0

    davezawadi:

    Whatever we do there is a large energy cost in getting sunlight (fossil fuels, solar, wind) to an energy form we can use. Sensible economics says all these should be considered and costed. Have you noticed the way in which this is avoided by everyone from Government to consumer?




    Except that as far as "emission-free" cars are concerned, there is often now an asterisk leading to "at the point of use".

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    Jaymack:

    I cringe when I hear or see plugtops, they are 13A plugs, likewise when some call current - juice. . .


    Jaymack. .   



    It is the jargon of the trade, isn't it! "Plugtops" you will find in catalogues, whereas "juice" is more colloquial. Another jargon term is "luminaire" for light fitting.


    I tend to avoid speaking in jargon unless to like-minded people; I like to be understood. A term which irritates me is "plug-socket". It is not jargon; it is a silly expression promoted by the media
     

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