A lot depends on the construction of the LED. An individual element inside one of these compound devices, when operated properly will have about 3.5V to 4V across it (this is a very rough estimate).
If these are arranged in multiple strings of 3, the LED is nominally a 12V device, if in strings of 6, then it is nominally a 24V device. And clearly these are not the only options, so the nominal voltage can vary widely.
What is most important for correct operation is the current. It might be that each string of these elements is rated to operate at up to 50mA. If you have 6 of these in parallel, the array is rated for up to 300mA.
One major problem is that the voltage is not fixed. As the elements heat up, the voltage across them necessary to maintain the desired current falls (this is exactly the opposite to what a light bulb does). If LEDs are supplied with a constant voltage, this causes the current to increase as they heat up. Because of this increased current they heat up further, lowering the required voltage, thus increasing the current heting them more... and so on until they fail.
As a consequence of this behaviour, LEDs (especially high power LEDs) are driven from a constant current source. The effects of heating now result in slightly lower power, so the system becomes stable and nothing burns out.
Unfortunately, if you ever purchase a high power LED it will be rated with a power and a nominal voltage (if you're lucky). It's up you you to determine the current (divide the power by the nominal voltage) and get a suitable driver.
Because the voltage can vary, constant current sources (similar to your LED driver) will generally specify a nominal power, a current, and an output voltage range.
So, to match a LED with a driver:
- Determine the current required by the LED
- Choose a driver with the appropriate power rating delivering the current calculated above
- Check that the output voltage range for the driver includes the nominal voltage for the LED
Unfortunately, LEDs can be sold as something they're not, and so can drivers. However, in general you can probably argue with your supplier if the actual capabilities or specs are not what you were told they were when you bought them.
Another thing you may not have considered is that LEDs similar to the ones you're using require heatsinking to keep them cool. If they are allowed to operate without a heatsink at anywhere near their rated power, they will heat excessively and fail quite quickly.