Why is this LED not 20 Watts?

[Herschel Peeler]

I ordered off of E-Bay a combo 20 Watt LED and a 20 Watt driver for an application that I have.
When I received it I tested it with a meter that I made up which shows the voltage, Amperage, Watts and Power.
The combination of the driver together with the LED showed as 9.1 Watts and not the 20 Watts that I wanted.
I suspected the driver was the cause so I tested the driver by wiring an existing 30 Watt LED ( 3-series of 10 ) and it showed when tested to be again only 9.1 Watts.
What do I do now, the driver cannot be used with 10 Watt LED's due to the voltage and under drives all of my LED's on hand.
I would appreciate your thoughts on this driver I have linked an image of the LED and driver for viewing.

View attachment 30047

Thank you in advance.

It looks like they were sold as a set and should be a match, but that does not appear to be the case.

 

[Al Slitter]

Yes it was supposed to be a matched set, however the manufacture decided to save some money by making the driver a 10Watt equivalent device.
The seller said he new nothing of this but I am not convinced as he still selling these sets on E-Bay!

 

[Herschel Peeler]

Yes it was supposed to be a matched set, however the manufacture decided to save some money by making the driver a 10Watt equivalent device.
The seller said he new nothing of this but I am not convinced as he still selling these sets on E-Bay!

I got my high power LEDs from Electronic Goldmine. They also sell suitable heat sinks and fans. I don't know what your LED is rated at for voltage and current so it is hard to say if your driver is correct. The seller seems unreliable.

 

[(*steve*)]

Do you understand how LEDs work? ...You supply a known constant current and the voltage "falls into place". (And of course, the power then falls into place.)

I'm pretty sure we're onto that.