Author Topic: Create light for high-speed shooting 1500w  (Read 6852 times)

SergeyKashin

  • Jr. Member
  • **
  • Posts: 79
    • View Profile
    • https://www.instagram.com/sergey.kashin/
Create light for high-speed shooting 1500w
« on: January 14, 2021, 04:13:19 PM »
He started developing his own light for high-speed video shooting. I finally got my LED (1500w 36v, $550) and a radiator for cooling ($200). Now the task is to combine all this to find a pwm with high khz for dimming and develop a complete system for cooling this LED.

Nikon1

  • Hero Member
  • *****
  • Posts: 656
    • View Profile
Re: Create light for high-speed shooting 1500w
« Reply #1 on: January 14, 2021, 04:28:00 PM »
I also planed out a complete Power supply system for one of those once, but never got around building one, only know those 1200W chips for far over 1k, and then there is also shipping and Taxes additionally, so way too expensive to be worth it. 550$ on the other hand is a entirely different story. can you link where you got your Chip and Block from?
 .
 I planed on using 6 of those, one for every one of the sections of the LED. Those can be dimmed by adding an External Potentiometer and replacing the one on the board with the External one. Feed with Two Powerfull 12V PC-Powersupplies or one beefy server one (propably still a good idea using two even from the Server ones, as this whole thing will draw way more than 1200W, cause the Converters also have Losses, so have at least 1500W of 12V-Power Ready, or closer to 2000W total if you end up going with cheap No-Brand China Power-Supplies).
 .
 https://www.ebay.de/itm/400W-15A-DC-Step-up-Constant-Current-Power-Supply-LED-Driver-Boost-Converter/273562739111?hash=item3fb19c21a7:g:29QAAOSwjMtb7l~b .
  .
 #EDIT#:  Any Plans on the Radiators yet?
« Last Edit: January 14, 2021, 04:33:00 PM by Nikon1 »

SergeyKashin

  • Jr. Member
  • **
  • Posts: 79
    • View Profile
    • https://www.instagram.com/sergey.kashin/
Re: Create light for high-speed shooting 1500w
« Reply #2 on: January 14, 2021, 05:01:04 PM »
I think it is better to immediately take a 36 volt power supply than to use additional step-up converters. There will be less unnecessary wires. I found a couple of pieces in my city for 36 volts 3000 watts of bu, for about $ 200

I talked to those who use similar LEDs, but they bought more expensive. For cooling, they use chillers
I considered buying a chiller in my city, but they are industrial and large, and these are not very suitable for the home. So I think to try a couple of circuits from the radiator from the computer with water cooling for 4-5 coolers 120mm

If you are interested in buying such an LED, then I plan to order a second one for myself, but there you need to order a batch of 20 pieces. If there are so many people, then perhaps they will make it a little cheaper by 20-50 dollars
With delivery and taxes I think there will be no problems

Nikon1

  • Hero Member
  • *****
  • Posts: 656
    • View Profile
Re: Create light for high-speed shooting 1500w
« Reply #3 on: January 14, 2021, 05:19:06 PM »
ok, directly using a 36V PSU can also Work, but make sure to use some Kind of current Limiter. Those big LED-Chips actually dont care that much about Voltage as they do about current. Each one of the 6 Chanels this Chip has needs exact current to Specification on the Datasheet, if you feed them Fixed Voltage from a big PSU, some or even all of the Chanels can draw more than they should, and that will dramatically lower livespan of the Chip. i think going over by 5-10% in current allready lowers Livespan by a lot. So you need a Dedicated Current Limiting Circut for every one anyways. Nice Thing about those Voltage Boost-Converters i linked is, that they allready have built-in adjustable Current-Limiting. So you can Set every one of those 6 Drivers to the Current your LED Needs (or go 1 to 2% under for Extended Livespan), and use The Voltage control Potentiometer as A dimmer Function. You can Try using the 36V PSU directly, but i personally would be afraid to Damage such a Expensive Chip or lower the Livespan by doing that. If you actually end up doing that, i would at least reccomend you to power each one of the 6 chanels up individually with that PSU and measuring the Current it actually draws, and if its over specified Current, adding a (powerfull enough) Resistor of correct Value in between that chanel and the PSU to make sure, none of the Chanels draws to much and will fail soon because of that.
 .
 So thats what i would do at least, yours may also work just fine, but i designed mine to work 300% Sure and Really Long term, so i figued a propper Current Limiting Circut would be needed, and because just Heating it away with a Clasic Linear Current Limiting Circut would not only be rather wastefull, but would also create impressive amounts of heat for the kind of Load its supposed to drive, i figured those Step-Up-Driver Boards would be easiest solution.
 .
 However, if you can get your entire Power Supply Stage done with a single unit and 200$, that has its point of relevance. Still would make sure to at least check the Current, cause its not usually best practice to just put LEDs of any kind in paralell without some kind of current Limiting, even be it done by some Resistors.
« Last Edit: January 14, 2021, 05:23:57 PM by Nikon1 »

SergeyKashin

  • Jr. Member
  • **
  • Posts: 79
    • View Profile
    • https://www.instagram.com/sergey.kashin/
Re: Create light for high-speed shooting 1500w
« Reply #4 on: January 14, 2021, 05:31:02 PM »
For adjustment, I will look for pwm, at the moment I found only 1000 watts of power, but I need it to be able to adjust 2000 watts. Also a very important indicator is the refresh rate (Khz) it should be 150 and higher. Therefore, a conventional potentiometer will not work, you need a complete integrated circuit for power adjustment


SergeyKashin

  • Jr. Member
  • **
  • Posts: 79
    • View Profile
    • https://www.instagram.com/sergey.kashin/
Re: Create light for high-speed shooting 1500w
« Reply #6 on: January 14, 2021, 05:39:55 PM »
First I do not know what it is, I have not encountered such things.
The second gives a maximum of 30 volts at the output, and we need 36 volts

Nikon1

  • Hero Member
  • *****
  • Posts: 656
    • View Profile
Re: Create light for high-speed shooting 1500w
« Reply #7 on: January 14, 2021, 05:51:05 PM »
The IGBT, that big Chip is an High Power Electronic Switch. Basically a Really Beefy Transistor, but with an Input Circut allready (kind of, still would propably need a driver stage for 150khz). The Second one will just generate the Signal, this is not to feed directly into the LED, but to give an control Voltage to the Big White Chip, the IGBT, to make it Switch on and off at 150kHz with variable duty cycle. So you would put the IGBT Power side between the PSU and The LED and connect the Signal Generator to the Signal Input Pins of the Big IGBT an the IGBT will do the Switching on and off. Basically a DIY PWM which can Handle Crazy amount of power. Those Big IGBTs can handle quite some Load.

Nikon1

  • Hero Member
  • *****
  • Posts: 656
    • View Profile
Re: Create light for high-speed shooting 1500w
« Reply #8 on: January 14, 2021, 06:00:41 PM »
The IGBT, that big Chip is an High Power Electronic Switch. Basically a Really Beefy Transistor, but with an Input Circut allready (kind of, still would propably need a driver stage for 150khz). The Second one will just generate the Signal, this is not to feed directly into the LED, but to give an control Voltage to the Big White Chip, the IGBT, to make it Switch on and off at 150kHz with variable duty cycle. So you would put the IGBT Power side between the PSU and The LED and connect the Signal Generator to the Signal Input Pins of the Big IGBT an the IGBT will do the Switching on and off. Basically a DIY PWM which can Handle Crazy amount of power. Those Big IGBTs can handle quite some Load.

 Ok, nevermind, just looked into the Datasheet of that particular one, and the reccomend only using it up to 20kHz, guess 150kHz will be hard to do with Those bigger IGBTs, cause they propably all are around there. But some Smaller Mosfets should Work.

Nikon1

  • Hero Member
  • *****
  • Posts: 656
    • View Profile
Re: Create light for high-speed shooting 1500w
« Reply #9 on: January 14, 2021, 06:15:30 PM »
https://www.littelfuse.com/~/media/electronics/datasheets/discrete_mosfets/littelfuse_discrete_mosfets_n-channel_hiperfets_ixfb300n10p_datasheet.pdf.pdf
 Found one, that will work for sure, but dont know if you can find them for sale anywhere, but there will be for sure something similar, just a powerfull HF-Mosfet.  That one here can disapate 1500W on its own if cooled correctly and handle 100V at 300A Load Switching for 200nS pulse Times, so 5MHZ at 50% Duty Cycle. Still pleny of overkill for your use, smaller ones will work too.
 Guess for that kind of Power you will propably need to start building some PWM on your own or use multiple smaller ones for each chanel?

Nikon1

  • Hero Member
  • *****
  • Posts: 656
    • View Profile
Re: Create light for high-speed shooting 1500w
« Reply #10 on: January 15, 2021, 06:47:51 AM »
For adjustment, I will look for pwm, at the moment I found only 1000 watts of power, but I need it to be able to adjust 2000 watts. Also a very important indicator is the refresh rate (Khz) it should be 150 and higher. Therefore, a conventional potentiometer will not work, you need a complete integrated circuit for power adjustment

 This still kept me thinking. What about using a PWM unit for one of the Strings (power of a single Section of the Big Chip would be 250W), a 1000W or even smaller one should easily be able to handle that, and then just use simple mechanical Switches to Switch the other five strings of the Chip on, if more power is needed. This way you can have 0 - 250W Adjustable Power and then add Power in steps of 250W to make a fully dimmable 1500W LED basically.
« Last Edit: January 15, 2021, 06:50:42 AM by Nikon1 »

SergeyKashin

  • Jr. Member
  • **
  • Posts: 79
    • View Profile
    • https://www.instagram.com/sergey.kashin/
Re: Create light for high-speed shooting 1500w
« Reply #11 on: January 15, 2021, 06:54:32 AM »
I want to find 1 ready-made pwm, but I don't have the experience and necessary knowledge to collect it myself

Nikon1

  • Hero Member
  • *****
  • Posts: 656
    • View Profile
Re: Create light for high-speed shooting 1500w
« Reply #12 on: January 15, 2021, 07:00:34 AM »
Are you aware, that this Big 1500W LED Chip is basically 6 seperate LED Modules built into a single Unit? thus you only need one of those to be controlled by PWM, meaning you can use a way smaller one. So Brightness adjustment would be like switching on between 0 and 5 of the Other Parts of the LED and then setting the Brightness fine-Adjustment by the PWM for the Remaining one. Needs one ready to buy PWM and just usual Switches, like A Mechanical Power button.

SergeyKashin

  • Jr. Member
  • **
  • Posts: 79
    • View Profile
    • https://www.instagram.com/sergey.kashin/
Re: Create light for high-speed shooting 1500w
« Reply #13 on: January 15, 2021, 07:12:25 AM »
I asked radio amateurs about a single potentiometer for controlling multiple PWMs at once, they said that this can not be done. This here most likely will have to put some kind of gearbox to control 6 pieces at once

Nikon1

  • Hero Member
  • *****
  • Posts: 656
    • View Profile
Re: Create light for high-speed shooting 1500w
« Reply #14 on: January 15, 2021, 07:27:18 AM »
I asked radio amateurs about a single potentiometer for controlling multiple PWMs at once, they said that this can not be done. This here most likely will have to put some kind of gearbox to control 6 pieces at once

 Well, i am an Radio Amateur myself, and this can be done multiple ways. first off, there are Stacked Potentiometers. i am pretty sure i seen more than 3 Stacked, but they seem to be very hard to find these days and very expensive as they are considered Audiophile Parts apparently... Best thing i can find right now:
 https://www.banzaimusic.com/MEC-M-87115-Stacked-Pot.html
 .
 Then there is this style of Potentiometer, which when soldered onto an PCB in a Stack behind each other can be connected easily with some Kind of Rod (maybe needs some drilling in the Middle and some Glue, but you will get it working).
 https://www.conrad.de/de/p/piher-pt-15-nh-10k-trimmer-linear-0-25-w-10-k-270-1-st-431893.html
 .
 And then there is also Linear Style Potentiometers, which can also be connected VERY easily with just mounting them Next to each other and Connecting the Lever thing on top across all of those you want to connect.
 https://www.conrad.de/de/o/schiebepotentiometer-0241780.html