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LED lighting in domestic applications (again)

Hello All,


This is my first posting so please be gentle with me.  I read one of the threads some time ago about the problems with LED lighting in either the home or small offices. One of the issues evident with LEDs, as already mentioned elsewhere is that the transformer rectifier circuits have to be built into each and every light fitting. While the LEDs themselves may last 10k or 20k hours, the control circuits certainly do not ( based on personal experience of LED lighting in my own home).


I got to thinking about how the LED fittings could be made more robust in order to achieve the claimed lifespan and also how new builds or retrofitting could make use of the energy saving potential better. There are many disadvantages of having a DC network in the traditional sense to power lights, switches would burn out quickly, lights would fail due to spikes when being energised are examples. What I thought was, why not split the switching circuit from the lighting circuit? What if we were to use a touchpad with a wireless transmitter instead of a light switch? This could be powered by the nearest mains point, have a unique network address and by association, control the lights in that area. So we have a means of controlling the lights, now to power them. Why not have a control unit that contains a transformer rectifier  and powers the individual lighting circuits all spurred off the control unit. The control unit would receive on/off commands from the light switch and using solid state relays, energise the relevant circuit. Alternatively, there could be a number of control units located around the home/office controlling a smaller number of light circuits. The LED light fittings themselves could then be of much simpler construction, reducing cost and prolonging their life. The control units would be more robust than the cheap components found in current LED lights thereby improving reliability.


Does my idea above seem feasible? This would work best in new builds but could be retro fitted relatively easily.


Kind regards


David Howard MIET
  • Or we could just spend a little bit more just buying lamps that aren't made by companies that penny-pinch on every component.  That, and making sure that the LED lamps have adequate cooling so as not to cook the power supply components.


    That sounds a lot simpler to me.  And probably cheaper.
  • The 1mm 230v lighting wiring we continue to install is a throw back to those now obsolete incandescent light bulbs.   The LED lights we now fit only come with those extra components to accommodate the wrong supply that they are connected to.


    If we think LED is here to stay (surely??) then we need to be looking at solutions such as David's.


    I suppose that in this age of swift change we need to be careful that we don't "jump the gun" however I fear that the British electrical establishment could be described as a tad conservative and change won't come easy.
  • The problem is not that there are systems that seperate LEDs and their AC-DC conversion (drivers) it is that there is no standardisation between them, and they need to be bought as a matched pair, so you can't easliy do what you envisage.

    Ideally agreeing on say 48, 24 or 12V +/- 10% ,  and all LED fittings then are aranged into strings of dies and has enough series R to sort itself out on that voltage, would be great. This is not what has happened, we have several constant current standards, several constant voltage standards, and it is all a mess. And then the layout is all wrong, and we may not really want light fittings at all in the conventional sense.

    I suspect a standard or 2 will emerge, but it will be like the USB phone charger standard, arriving after about a decade of total confusion has caused pain and loss to early adopters.

    Currently in in terms of reliabilty of lamps with inbuilt supply, some of the best lamps I have seen are the ones with no electronics beyond a series capacitor,  a bridge rectifier, and then very long strings of LEDs of 100V  or so and a bit of some current limiting. They are also good in terms of EMC emissions, as there are no supersonic square waves with edges in the hundred nanosecond time scale.
  • We must not lose sight as to what we are wishing to achieve! Namely, the illumination of a dark space. Nothing more, nothing less.

    We don't need banks of computers to achieve this!
  • Okay, so using your logic, we would all still be using gas lighting! Do you argue against putting smart features on fridges, freezers and washing machines? After all, they are only there to keep cold things cold and to clean clothes.


    If we had centralised transformation/rectification instead of each LED fitting having their own then better quality and reliability should become easier to achieve. Instead we currently pack everything into the space envelope for a GU fitting. This also has environmental impact in that we would manufacture less "disposable" items as LED light fittings currently do not last the claimed amount of run time. I just feel that there are smarter ways of providing LED lighting that could be adopted should there be the desire and drive to push it, supported by updated wiring regulations to suit. An obvious starting place being new build property.

  • Do you argue against putting smart features on fridges, freezers and washing machines? After all, they are only there to keep cold things cold and to clean clothes.




    yes, I most certainly would where there is no clear benefit.Otherwise all we add are sources of failure and expense and make things hard to repair. Actually, as a designer of electronics, looking at the ones in the shops now,  I reckon we reached peak fridge about ten to fifteen years ago, and the rest is not real progress, but just marketing fluff. Thicker insulation would be more sense.  In terms of washing machines I have just replaced the inverter transistors for the brushless motor, after about 6 years, so it is out of warranty. For most folk that would make it scrap. There are more folk capable of repairing something with an induction motor or brushes.

    But then I am old fashioned, I  like to buy things using real money, and use my phone for  talking to folk who are remote, not to allow me to simultaneously watch video and walk into lamp-posts.