If efficiency is the goal then don't use 12VDC. Go up to 36 or 48 volts at lest. The best systems are like those use in the solar industry at 400+ volts DC. Power loss in the wire is "I squared R" so there should be an incentive to reduce I. Doubling the voltage reduces loss by 4X doubling it twice to 48V cuts the loss by16x. The LEDS do NOT run off 12 volts. Your power supply might accept 12V but the output is "constant current"
Do NOT use a "low dropout" regulator.. They voltage regulation by converting excess voltage to heat and wasting it. You want a switch mode supply. Those can be very efficient. If you have a little box that takes 12V and powers LEDs it is almost certainly a switching mode power supply. In the worst case where you have one 12V battery and you want to power one LED and you use a simple low dropout regulated about 90% of the power is wasted while on the other hand a switcher type regulator can waste less then 5% if setup right. 12 volts DC is a very poor distribution system. The cost of the wire is so much and almost noting runs on 12V. It has to be converted using some kind of power supply A power supply to takes AC and converts to constant current for LED uses no more or less input power then a 12V power supply. Where you get the gain from DC is that you loose the need for the DC-> inverter, you simply distribute the DC. On Tue, Apr 17, 2018 at 3:49 AM, Lester Caine <les...@lsces.co.uk> wrote: > On 17/04/18 11:14, Chris Albertson wrote: >> >> If you are thinking about LED lighting, don't try and replace incandescent >> bulbs. That works and is what people do but if you are building from >> scratch yu design the LEDS into the architecture. > > > I've replaced almost all the existing light bulbs with LED ones. The best > change was in the workshop where the fluorescent tubes are now LED versions. > Instant start and no flickering! But while fitting them I began to wonder if > now is the time the lighting circuits in the house simply move to 12V DC? > The kitchen has a number of 12V transformers powering the lights. The LED > bulbs are taking a 20th of the power the original bulbs used so one power > pack could power the whole lot with power left over! But thinking about the > 'off grid' situation, a 12V battery with a low dropout regulator could > provide lights efficiently. While bigger appliances need 'mains', quite a > number around here are also 12V powered, so 'building from scratch' could a > DC supply direct off a storage system be an alternate way forward? > > -- > Lester Caine - G8HFL > ----------------------------- > Contact - http://lsces.co.uk/wiki/?page=contact > L.S.Caine Electronic Services - http://lsces.co.uk > EnquirySolve - http://enquirysolve.com/ > Model Engineers Digital Workshop - http://medw.co.uk > Rainbow Digital Media - http://rainbowdigitalmedia.co.uk > > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users -- Chris Albertson Redondo Beach, California ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
