The big ebay LED floodlight scam.

[Paul Moir]

I'll give you another more radical example.  What if I gave you 1000 lux at 1000nm.  Not very bright huh?

That's impossible because lux takes into account the sensitivity of the human eye which is 0 at 1000nm: you'll cook your retina before you'll see it!
http://en.wikipedia.org/wiki/Lux

Thank you, I learned something new today! 

[Simon]

they are a life threatening unsafe product and a possible fire hazzard

So true. 99% of what's sold on the bay is electronic junk.

For people to think about using them in critical applications, light mains lighting, it shows just how stupid humans can be.

You'd be surprised at the amount of recalls "good" manufacturers get. I've lost count of how many cars. And don't forget that any manufacturers looks at the bottom line: is it worth recalling the lot or letting a few people get killed or injured and pay them compensation. I kid you not, that is how business thinks!

[Simon]

It depends on how the "wattage" is defined.

It is not uncommon (actually, almost universal), for example, for a CFL bulb consuming 6w of electricity to be labeled 60w for its ability to generate the same light as a 60w incandescent light bulb. This makes it easier for consumers to cross-shop light bulbs and makes the marketing easier too.

You don't have to agree to its approach but you would be a fool for not recognizing its merit.

A 6W CFL is most certainly not equivalent to a 60W incandescent. When they came out it was 25W = 100W, now you might be able to stretch it to 20W = 100W

[Simon]

I'm working on the rule of thumb (no knowing how many lumens my shitty yellow CFL's make) that any LED light that does at least 80 lm/W can replace a CFL of W*0.66-1.0

I replaced a 23W CFL with a 10W 800 lm and it's the same to me. A 35W CFL with a 10W 800 lm and granted there is less light because it's not yellow I'm happy with it as it is.
I took two 14W CFL's out of one room and replaced with 1 10W 800 lm, i left in the 11W CFL and aim to replace that with another 10W 800 lm so I'd have replaced 39W of CFL with 20W 1600 lm
Other small lights like top and bottom of the stairs are going to get 3W LED's that claim 280lm
The kitchen that I have already downgraded from a 80W fluorescent to a 54W one will likely get 20W 1600 lm of LED, all in all I'm taking out quite a few watts of power for realistically the same light.

[westfw]

I replaced a 23W CFL with a 10W 800 lm and it's the same to me.

Really?  Most of the 23W CFLs I see are advertised as about 1600 lm.

Interestingly (to me, anyway), I had a relatively difficult time finding 25W-equiv LED bulbs...

[Simon]

oh sure, 1600lm, at what colour ? you can't see yellow and sub yellow very well, I could probably do with a few more watts but I'm happy enough

[Simon]

I think you mean 80lm/W most seem to be about there, you can in theory get as good as 120lm/W but I'd think they are expensive.

[Zero999]

I've noticed that US bulbs seem to be really inefficent, so it wouldn't surprise me if a 23W CFL was quite dim. 80W/lm is extremely average for an LED bulb, most of mine are 100W/lm.

I don't know about CFLs but the US have slightly more efficient incandescent lighting because the lower voltage means the filament can be thicker, meaning it can work at a higher temperature, for a given lifetime.
http://en.wikipedia.org/wiki/Incandescent_light_bulb

The lower voltage is why CFLs over there are less efficient? I haven't found anythign to confirm this.

[Simon]

Maybe the lack of easy comparison has encouraged manufacturers to just claim "60W equivalent" rather than actually produce good bulbs.

It's an advertising war, there are no real standards so each time one manufacturer wants to outdo another they can just make up new better figures. Hence i would rather know lumens and colour temperature, that was i know the amount of light being produced and I know if it's in a colour that I can actually see because I can't trust a government or regulatory body to enforce a decent standard I have to come up with my own.

Any bulb now rated as equivalent wattage with no lumen rating will be a scam, there is such a variation in technology efficiency that watts is meaningless.

[Kjelt]

You know that in the lighting industry there are many standards and common criteria to judge a lamp. But unfortunately this is insider jargon and they don't always share these figures since it is meaningless for 98% of the people.
For instance the Life time, lumen maintenance and failure rate is a very good and important one:

Life time, lumen maintenance and failure rate

The L value: the light output of an LED Module decreases over the lifetime, this is characterized with the L value. L70 means that the LED module will give 70 % of its initial luminous flux. This value is always related to the number of operation hours and therefore defines the lifetime of an LED module.
As the L value is a statistical value and the lumen maintenace may vary over the delivered LED modules.

The B value defines the amount of modules which are below the specific L value, e.g. L70B10 means 10 % of the LED modules are below 70 % of the inital luminous flux, respectivly 90 % will be above 70 % of the initial value.

The C valueThe percentage of failed modules (fatal failure).

The F value is the combination of the B and C value. That means for F degradation complete failures are considered, e.g. L70F10 means 10 % of the LED modules may fail or be below 70 % of the initial luminous flux.

So a ledmodule in a fixture with a given L60F50 at 30000 hrs means that 50% of the leds on the ledmodules in the fixture wll have less than 60% of their initial rated luminous flux left.
So to judge what you want to buy this figure is as important as how many lumens/watt you will get.
A flashlight (the ones that flash one times) have an enormous amount of lumens/watt but it lasts only a tenth of a second. 

[Simon]

Those jargon values are the ones that need to be fixed in law so that the consumer need not worry about being ripped off. Of course expecting a law about engineering matters is about as good as asking father xmas for it!

[Kjelt]

Perhaps you're right but that goes for so many things. I never ever had the fuel/mileage figure that was given for a car when I bought it 
And I have a suspision that I am not the only one 

[Simon]

As I say I'm happy with that sustem but many ebay goods are sold with no lumens stated but a wattage equivalence and stupid things like 6W = 60W