Many of the drivers for LEDs are what are called Current drivers. The put out a specific current and vary the voltage supplied. This works great because LEDs work best at a specific amperage and each LED requires a slightly different voltage across it to get that current. this is because no two LEDs are exactly alike and also their resistance changes as they heat up or cool down.
Volts = Current X Resistance.
So if you use a voltage supply, as the resistance changes, the current naturally changes to compensate. This will cause the LED brightness to fluctuate.
Where as if you are using a constant Current supply, the voltage will change when the resistance changes and the current will stay the same. The LED will maintain the same brightness as it heats up or cools down.
Think of amps as flow though a pipe. Every point in that straight piece of pipe has the same ammount of flow. So every point in a single wire has the same amperage. If the pipe in this example branches off at a T, then the flow in the two branches adds up to the original flow. Same thing with current in wire. If the wire is spliced, part of the current goes one way, and part goes the other. But it will add up to the total amperage that went into that point.
What goes in goes out.
If you are looking for a driver to run your 5, 10 watt LEDs, you need a current driver that puts out 1 AMP of current and also up to 50 or more.
Remember
Power = Current X Volts
so
50 Watts = 1 amp x volts
Solve for volts by dividing both sides by 1 amp and you get
50 Watts / 1 Amp = Volts = 50 Volts.
So for the 3 Watt LEDs that work best at 700 mA, you would need a driver that puts out 700 mA or one that can be adjusted to put that out. Then you need to figure out how many you need by looking at how many LEDs one will drive.
I suggest shooting an email over to the guy at
Rapid LED Home Page He should be able to recommend a set up that will work for you.