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I'm having an issue that I can't seem to resolve. I have 100 watts rgb leds that I'm driving with constant current drivers (https://www.amazon.com/gp/product/B019W4C5IE/ref=ppx_od_dt_b_asin_title_o00_s00?ie=UTF8&psc=1) I replaced the trimmer pot for voltage with a b10k so that I can easily dim the lights, setting the max current on the cc pot so that it doesn't go above my wanted value. The led chips I'm using have g and b starting to produce light at around 27 28v which is fine as my input current source is 25v max (6s lipo battery that will decrease to around 21.5v when empty ) and these are step up regulators. The problem comes from the red leds that start lighting at 20v and be full light around 25v. These regulators will provide not less than input voltage which prevent me from dimming the red channel. I tried putting a step down to 12v before the step up, it works, but now I'm facing another problem which is that when I shutdown the whole system with a switch and turn on again, the red channel will only give around 1.5 amps on the red channel. I have to turn down the voltage control pot down and then all up again to get back the set 6.5 amps again and I don't understand why.

How can I work this around and why would that be happening?

Thank you

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  • \$\begingroup\$ what's a b10k? Why do you think you can replace a trimmer pot with anything but a resistor? Is it possible your drivers are simply not up to the task (if in doubt, amazon isn't the source for electronics at all) \$\endgroup\$ – Marcus Müller Sep 19 '20 at 13:59
  • \$\begingroup\$ B10k is a linear 10k potentiometer so exactly the same as the thing I replaced but in bigger format. I can't find high power constant current drivers that will have enough power anywhere but on Amazon, if you have an alternative I'd be glad to hear it, it's not a money issue or anything, it's just, if I could find a 250-300w at least constant current driver buck boost, I world not be here asking about this \$\endgroup\$ – ulkar Sep 19 '20 at 14:09
  • \$\begingroup\$ Well then sorry to tell you that you're wrong, I've been pulling 200-250w from two of them for a month now, they're being watercooled through the aluminum cooling plate in the back. Also I don't need a 300w boost I need a 300w buck /boost \$\endgroup\$ – ulkar Sep 19 '20 at 14:33
  • \$\begingroup\$ Do you even read what I'm writing? They're being watercooled with thermal paste and a huge custom made waterblock. I have an amp meter, there's 6.5 amps at 35V on the output \$\endgroup\$ – ulkar Sep 19 '20 at 14:41
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    \$\begingroup\$ ah right, sorry about that. Incredible effort just to use the cheapest possible converter, but clearly works. I'll clean up my comments. \$\endgroup\$ – Marcus Müller Sep 19 '20 at 14:49

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