Few observations..
"white" LEDS (in this case 3,000K) have three individual LEDs of Red-Green-Blue inside and they are coupled to specialized phosphors to increase their light output efficiency. The trade off being the three peak light output color outputs instead of a uniform light spectrum output as would be from an incandescent, sunlight or similar light source. Humanoid eyes perceive three peaked light output from LEDs as "white" photographic materials might not record light in the same way.. This is an important consideration due to the way variable contrast B&W papers work and how contrast grade control is done with VC black and white papers..
https://www.sciencedirect.com/scienc...3107051830029X
White LEDs typically have about a 3.5 volt forward voltage to make them go.. and this voltage changes as their temperature goes up. If the LEDs are driven with a constant voltage source, the current into the LED goes up causing an increase in light output and more heat generated in the LED. This is why LEDs are driven with a constant current source to reduce this baked in problem.
"Why Drive White LEDs with Constant Current?"
https://www.analog.com/en/technical-...t-current.html
~It is also why the power unit takes time before the LEDs can be powered to illuminate them as the power source uses negative feedback and more to control the current output into the LED.
Connecting the LED array in parallel is not good. This forces the power dissipation in the power unit to be a LOT more than it needs to be and aggravates the forward voltage issues that is baked into how LEDs work. Simply wire the LED array in series to stop this problem. Check the max output voltage on the LED power unit to determine how many LEDs can be wired in series and meet the LED power unit's specifications. This might be two strings of six LEDs each instead of twelve LED in series..
12 LEDs at 3.5 volts = about 42 volts needed at the driving current of 1(?) amp..
6 LEDs at 3.5 volts = about 21 volts per 6 LED string at the driving current of 2(?) amps total into the two LED strings.
Keep in mind, current to control LED light output intensity/power, NOT voltage as this varies with each LED and operating temperature.
There will be a time delay before the power unit can make the LEDs go. There are ways to make the power unit do "near instant on" this is a design detail that required knowing how all the individual parts of the system works on their own then, designing the system to allow each individual part to work at their ideal best.
Bernice
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