I´ve done some research but not clear solutions are given to this problem, so I will post my case here in case somebody can help. Thanks in advance.
I want to use a DC power supply to power up 121 LEDs. Each of these LEDs is taking 460 mA, so, mounted in parallel, I need an outcome of 55A for the complete LED series.
The problem comes now, the DC power supply that I have found most suitable (RSP 2000-24) can be configured at 21V minimum, and these LEDS need something in between 19V and 20V, so I need to drop the voltage from 21V to 19.5V with the 55A current flow. (They could probable work with the 21V but these LEDs are expensive and I dont want to screw it up)
I´ve found some resistors which can support up to 250W, so I could use several of them I guess... I suspect is not a good solution. I have also found some voltage regulators but none of them seem to stand the 1000W that I need..
Any ideas would be really appreciated!
EDIT: Thanks for your replies first of all. I will answer here the questions mentioned by Russell McMahon so we can tackle the problem better.
Why are you using those particular LEDs?
The set of LEDs working togheter will be used as a flash light for camera shooting. There will be 6 camera shots delayed 500ms among them. So the LEDs will be turned on 6 times each 500ms for a duration of just 1ms when the flash signal closes the circuit formed by the PSU and the LEDs. That is why I´m not regarding heat sinking, because they will only be shining for 1 ms.
Since the duration of the pulse of just 1ms, I think we may have problems with the Rise up Time & Setup time of the PSU, I´ve thought about using a capacitor so the current can flow immediately after closing the circuit´s switch and the LED´s can light up sincronized with the camera shot. Any suggestions on this issue are appreciated as well.
Do you need a high CRI?
Yes. Otherwise object colours will appear distorted in relation to reality.
How long do you want these LEDs to last?
As much as possible. They will only be flashing 6 times for 1ms each time the camera shoots.
Do you care or know anything about this manufacturer?
For the specifications I need, this manufacturer resulted to be the cheapest and fastest in delivery. Cree was more expensive and takes longer time.