LED Dimmable v non dimmable lm per watt

27 Jan 2008
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Llanfair Caereinion, Nr Welshpool
United Kingdom
B22d LED bulbs seem a lot harder to find than E27 or E14 so when I found a 11W 806 lumen bulb in Aldi I grabbed it and did not really think about it being dimmable.

However comparing bulbs where the lumen is given 1.4W = 71.4 lm/W, 3W = 83 lm/W, 11W dimmable = 73 lm/W and the 24W = 100 lm/W.

It does not matter lidi or Aldi E14, B22d, candle or globe the 3W = 250 lm. It seems from small sample I have as the size increases so does the lumen per watt except for the one marked dimmable. Internet hunt shows non dimmable 11W bulb as 1055 lumen or 96 lm/watt and the equivalent bulb size also changes from 60W to 75W.

However the dimmable 11W is energy rating A+ and the non dimmable energy rating A. This I expect is similar to freezer where you are allowed to use more power if upright than chest, built in then free standing, and T to N climate class.

With the bulb it seems we again have an "energy efficiency index" also for directional 90° and 120° have different rules. I have also found a reference to using external control gear both with LED and discharge lighting where allowance is made for losses with control gear. It would seem one corrects the watts used in calculations however can't find anything about dimmable other than a warning must be given on the packaging if not dimmable.

Since the dimmable LED was cheaper than non dimmable I was not really worried about being slightly less lumen/watt output. However I feel conned when a 11W dimmable with a lower output to a non dimmable is given a better energy class label.
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another point i have noted is bulbs with a lower range off voltages seem to be more efficient as in 200- 250v 6w bulb compared
with a 85- 250v 6w being perhaps 20% dimmer
this is using a meter to check the actual input watts
also i have found a 2W bulb brighter than a 4w actual w where 1.6 and 4.5w

now my finding are now out off date as the comparason is with bulbs up to 5 years old with this information its self about 2 or three years old

the point i am making really is the watts claimed may be quite a bit out from the actual rated and the light output can bear little relation to claimed levels

all the bulbs compared where bayonet or es bulbs in pendants
I note over 30 lumen there should be both an energy label and the lumen declared. Non of the spot lamps I have bought have either, So out of 12 lamps 4 have no lumen stated all bought in local shops. No distance buying.

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