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Lumen equivalents of halogen floods v Led

hertzal123
I am trying to find a replacement for 300W halogen floods.A search online gives halogen 300w as 5000/6000Lm.Looking at a Luceco  led flood in electrifix

catalogue,it claims 22W is equivalent to 300W halogen,but they only give 1800 Lm,so how can they be as bright as the 300W halogen?

Thanks for any help.

                                    Regards,

                                                Hz.
  • 0
    A lumen is a lumen and should represent exactly the same amount of light, no matter if this be obtained from a glowing filament or from LEDs or from the combustion of gas.

    In practice makers and vendors of LEDs tend to lie and exaggerate considerably, they use "Chinese lumens" that are no doubt related to Chinese watts produced by in car audio equipment.


    In the past LED vendors generally multiplied the wattage by ten in claiming an equivalent light output, so a 22 watt LED would be claimed as an equivalent to 220 watts of incandescent. These days they multiply by about 15.


    The light output of the halogen floodlights tends to be exaggerated also, but not as badly. It is common practice to take the LAMP output without any allowance for losses in the cheaply made reflector and cover glass.


    Ideally conduct a practical trial. If this is not possible then select an LED that is claimed to equal a halogen of the next largest wattage. So to replace a 300 watt halogen, use an LED that is CLAIMED to replace a 500 watt halogen.
  • 0
    The answer is that it cant! A rough guide is that LEDS are about 8 times as efficient as halogen, so you need something like 40W LEDs. Halogens give around 10 lm/ Watt so the 5000-6000 claim is also far too high. The colour is also different so perceived brightness is better for the LEDS. I suggest you get a 40 or 50W LED fitting and show the customer the difference (safer that way!). You need to emphasise that the LED life is much better than linear halogen lamps so save money in the long run.
  • 0
    That is a bit negative Broadgauge. The equivalents are well known and there are no leds yet that give 150 lm/W. They are gradually getting better, and whilst there can be some dishonesty, I find that 12W LED lamps are generally brighter than a 100W conventional, in fact more like a 150W one as the light is more directed downwards than a filament.  The light output is not only the lumens, it is also the directivity, and this is better from LEDs than a linear lamp and fairly poor reflector. The lumen value is integrated over a sphere, so can be quite misleading. Real brightness is measured in Lux, lumens received per squaare metre, and this is what really matters.
  • Former Community Member
    0 Former Community Member
    Well it could be based on the LED output remaining stable whereas with discharge lamps, the output deteriorates, so it could be a comparison based on output still available at half life or some other fraction.


    I don't know how much a halogen lamp output deteriorates with life.


    Regards


    BOD
  • Former Community Member
    0 Former Community Member
    perspicacious:


    I don't know how much a halogen lamp output deteriorates with life.

     


    In some cases 100% every five minutes! ?

    I've been replacing fluorescent lamps with LEDs in several buildings. Going on manufacturers so-called lumen figures I'm either going to be suffering from burnt retinas or groping around in the half light! In practice I've just gone ahead and swapped them over and generally been satisfied. For example we've recently changed a community hall over from 14 70W twin HF fluoros to 14 single 6ft 4000k LEDs. On paper the fluoros should be about 13k lumens total per fitting, the LEDs about 7k so I'd be thinking the light levels will be reduced. In practice the lighting levels in the hall appear to be the same. I did consider going for cooler temp LEDs such as 3000k to replicate the fluoro lighting but 4000k seems perfectly okay without the blueness you get with higher temps.

    One downside I have found with LEDs is the propensity of the drivers to fail, certainly more frequently than the fluoro fittings.


  • 0
    Actually it gets better BOD!
  • 0
    Thanks for all the replies,I may go with the 40W or 50W leds.

                                                                                    Regards,Hz
  • 0
    hertzal123:

    Thanks for all the replies,I may go with the 40W or 50W leds.

                                                                                    Regards,Hz


    Just noticed the Luceco 38W led flood has a power factor of 0.5,so not as cheap to run as they appear.

                                                                                                                                                 Hz


  • 0
    hertzal123:
    hertzal123:

    Thanks for all the replies,I may go with the 40W or 50W leds.

                                                                                    Regards,Hz


    Just noticed the Luceco 38W led flood has a power factor of 0.5,so not as cheap to run as they appear.

                                                                                                                                                 Hz




    Poor PF usually won't make much difference to running costs as normal metering records kWh rather than kVAh (except perhaps for some industrial situations where there might be a penalty for poor PF).

        - Andy.


  • 0
    from experience, id replace 300w with a 20w LED, 500w with a 50, 200w metal halide with 100w led 400w metal halide with 150w or 200 in some situations


    thats from trialling, and the light output is quite different so its not all about watts. LEDs give light in a closer range than halogen, so a lot of the halogen lumens arent as useful as the lumens from LED, that's why lumen per lumen they don't align.

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