100w LED Light need assistance with design

Discussion in 'Homework Help' started by sscsksl, May 23, 2016.

  1. sscsksl

    Thread Starter New Member

    May 23, 2016
    8
    0
    I am looking for technical advice on how to build a project. Please see attached presentation. Here are the questions. Thank you for your consideration.

    1.Circuit breaker - correct item and size to limit current? Is a 120k ohm resistor more applicable?
    2.Fuse, Is it needed? If so is 20A correct?
    3.Switch – can it handle 20A?
    4.Multimeter – If limited to 20 amps, is a shunt strap needed?
    5.Wiring Diagram - Is this correct?
    6.Resistor - Is it needed for a Pot? If so how many (2?) (as shown) and size (11k)?
    7.Pot – is 10K ohm correct?
     
  2. DickCappels

    Moderator

    Aug 21, 2008
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    That might work. Can you post the datasheet for your LED and the boost converter?
     
  3. sscsksl

    Thread Starter New Member

    May 23, 2016
    8
    0
    Yes sir
     
  4. sscsksl

    Thread Starter New Member

    May 23, 2016
    8
    0
    It is a PDF attached, were you able to open it?
     
  5. DickCappels

    Moderator

    Aug 21, 2008
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    That is the same pdf file you posted in post #1. Can you post the datasheet for the LED and the boost converter?
     
  6. sscsksl

    Thread Starter New Member

    May 23, 2016
    8
    0
    Sorry, It dawned on me what you were asking for once I resent the PDF. I put together a list of all the components. The first two are the items request. Thank you for looking at this!

    GEREE 250W Boost Converter DC/DC 8.5-48V to 12-50V Output Step-up Module Mobile Power Supply Max 10A

    Specification:
    - Module Properties: non-isolated step-up module (BOOST)
    - Input voltage :8.5-48V
    - Output voltage: 12-50V (adjustable)
    - Output Current: 10A (MAX) (Please enhance heat dissipation if more than 6A)
    - Output constant Current: 0.2 - 8A (please don't short the output to adjust the current)
    - Easy to drive 65W 90W dual-core notebook.
    - Conversion efficiency: 96%
    - working frequency: 150KHZ
    - Output Ripple: 2% (MAX) 20M-bandwidth
    - Operating Temperature: Industrial (-40C to +85C) (ambient temperature exceeds 40C, lower power use, or to enhance heat dissipation)
    - Dynamic response speed: 5% 200uS
    - over circuit protection: yes
    - Input Reverse Polarity Protection: yes
    - Size: 70*46*13mm


    LOHAS® 100W LED Chip Cool White Bulb High Power Energy Saving Lamp Chip

    Drive Voltage:30-34V;Chip power:100w
    Size (L*D):50mm*55mm Viewing Angle: 140 degree
    Cool White.Color Tempreture:6000-6500K
    Luminous(lv):8000-9000lm


    Yeeco® Digital Multimeter Voltmeter Ammeter DC 6.5-100V 20A Voltage
    Amperage Power Energy Meter

    C. Test Range and Display format:
    1.Power: test range: 0-2kW
    Less than 1kW, display: 0.0-999.9W
    1kW-2kW, display: 1000-2000W
    2.Energy: test range: 0-9999kWh
    Less than 10KWh, display: 0-9999Wh
    More than 10kWh, display: 10-9999kWh
    3.Voltage: test range: 6.50-100V(single-phase)
    Display: 6.50-99.99V
    4.Current: test range: 0-20A
    Display: 0.00-20.00A

    D. Specifications:
    1. Working voltage: DC 6.5-100V
    2. Test voltage: DC 6.5-100V
    3. Rated power: 20A/2000W
    4. Measurement accuracy: 1.0


    TE Connectivity W54-XB1A4A10-30 Circuit Breaker; Therm; Push; Cur-Rtg 30A; Panel; 1 Pole; Vol-Rtg 250VAC

    Brand Name

    TE Connectivity / P&B

    Part Number

    W54-XB1A4A10-30

    UNSPSC Code

    39121633



    ARCTIC Freezer A11 CPU Cooler for AMD, 150W Cooling Capacity, 3 Direct Touch Heatpipes, Vibration-Dampened Fan, 23dBA Noise

     150W Cooling Capacity Outperforms Stock Coolers, Supporting FM2/FM1/AM3+/AM3/AM2+/AM2

     3 Double-Sided Direct-Touch Heatpipes for Fast & Efficient Heat Dissipation

     92mm PWM Fluid Dynamic Bearing Fan on Vibration-Dampened Mount Operating at <23dBA

    Resistors 11K OHM OHMS 1/4W 0.25W 1%

     Power (Watts) 0.25 (1/4 Watts)

     Resistant 11K OHM

     Tolerance +- 1%

     RoHS LEAD FREE


    uxcell 10 Pcs 10K ohm 3 Pins 6mm Split Shaft Rotary Linear Taper Potentiometers w Knob

    Product Name : Potentiometer;Resistance Value : 10K ohm;Adjustment Type : Top Adjustment

    Type : Single Linear (Type B);Features : Knurled Shaft;Shaft Diameter : 6mm / 0.2"

    Shaft Length : 8mm / 0.3";Mounting Thread Diameter : 7mm / 0.3";Base Size : 16 x 7.3mm / 0.6" x 0.3"(D*H)

    Total Height : 24mm/0.9";Knob Size : 14 x 17mm/0.55" x 0.7"(D*L);Material : Metal, Plastic, Electronic Parts

    Weight : 99g;Package : 10 x Potentiometer w Knob


    ATC/ATO Water-resistant Fuse Holder - 10 AWG

    Heavy duty, in-line fuseholder for ATC/ATO type fuses. 10 gauge wire for up to 30 amp rating.


    GENSSI Auto Car Marine Boat Power Switch 4-pin (Stainless Steel Red LED Latching 18mm)

     Latching Type - Press On / Press Off

     Stainless Steel. IP65 waterproof. Up to 3A 250V AC Rated.

     4 Pin connections

     Requires resistor for the LED if using on 12V. Resistor included. Red LED. 3V LED.
     
  7. DickCappels

    Moderator

    Aug 21, 2008
    2,653
    632
    This might work, but the resistor may be a large problem. I cannot tell for sure from the information presented, but it appears that the power supply is intended to present a constant voltage to the LED, hence the need for a resistor. It would be far better to use a boost converter set up to supply a constant current. That way, you would not have to worry about getting a large enough resistor. The resistor problem is compounded by the fact that the LED voltage will drop, perhaps 10% as the LED warms up.

    You're talking about 3 amps for the LED. If you were going to use a series resistor to limit current, then you would have to find a variable resistor that would safely handle the 3 amps. A 10k pot would not work (10x x 3A = 3kv).

    I suggest you look for a LED driver that matches your needs.

    By the way, most of that 100W will be dissipated as heat and LEDs need heatsinking not only to protect the LEDs but also to maintain efficiency at high power. Have you considered how you are going to get rid of all that heat?
     
  8. sscsksl

    Thread Starter New Member

    May 23, 2016
    8
    0
    I need to absorb everything you have written. As far as the heat, I have selected this heat sink with Fan. Please let me know if this will not wick the heat away

    http://www.amazon.com/dp/B00HO9P0J6...lid=3GU2TTZF83SWA&coliid=I1NC2E8OH5P4LK&psc=1


    ARCTIC Freezer A11 CPU Cooler for AMD, 150W Cooling Capacity, 3 Direct Touch Heatpipes, Vibration-Dampened Fan, 23dBA Noise

     150W Cooling Capacity Outperforms Stock Coolers, Supporting FM2/FM1/AM3+/AM3/AM2+/AM2

     3 Double-Sided Direct-Touch Heatpipes for Fast & Efficient Heat Dissipation

     92mm PWM Fluid Dynamic Bearing Fan on Vibration-Dampened Mount Operating at <23dBA

    Resistors 11K OHM OHMS 1/4W 0.25W 1%

     Power (Watts) 0.25 (1/4 Watts)

     Resistant 11K OHM

     Tolerance +- 1%

     RoHS LEAD FREE
     
  9. sscsksl

    Thread Starter New Member

    May 23, 2016
    8
    0
    Would this be the correct Boost converter?
    http://www.amazon.com/DROK-Converte...ir-20&linkId=2393373c8f0129791a207dcc4128cff5

    DROK® 600W 12A DC Boost Voltage Converter 12-60V to 12-80V Step-up Power Supply Transformer Module Regulator Controller Constant Volt/Amp Car Regulated Laptop Battery Charger LED Driver Generator
    Parameters:
    Module Name: 150W boost module
    Module properties: non-isolated module
    Minimum voltage difference: 0V
    Two Input voltage optional: select the input voltage by adjusting the jumper on the back of the PCB
    Input/output Voltage 1: When Input DC 10-32V £¨aimed at application to wide input voltage)
    Input/output Voltage 2: When Input DC 8-16V (aimed at application to 3 strings of lithium battery and 12V accumulator)
    Output Voltage 1 : When Input DC 10-32V,Output 10-46V((adjustable, default 19V)
    Output Voltage 2 : When Input DC 8-16V,Output 8-46V(adjustable, default 19V)
    Input Current: 16A Max. (exceed 8A please enhance heat dissipation)
    Output current: 8A Max. (exceed 4A please enhance heat dissipation)
    Quiescent operating current: 15mA (12V to 20V, higher output voltage will increase the quiescent current)
    Output power: 90W(natural cooling), 150W(enhance heat dissipation)
    Capacitances:2x 470uF/35V(input) ; 2x 330uF/50V(output)
    Operating temperature: -40¡ãc to +85¡ãc
    Working frequency: 380KHz
    Conversion efficiency: up to 95%
    Operating indicator: Yes
    Short circuit protection: None
    Input reverse polarity protection: None (If need please install diode at input port)
    Installation: 4x 3mm screws
    Wiring: Terminals, Needn't solder, V-IN input, V-OUT output
    Module size: 60mm x 50mm x 20mm

    Testing:
    16V to 19V, output current 3A, efficiency 94%
    12V to 20V, output current 5A, efficiency 89.5%
    12V to 30V, output current 3A, efficiency 89.2%
    24V to 42V, output current 3A, efficiency 95.2%

    Some Applications:
    DIY a voltage Regulator, adjustable.
    The power supply for electronic equipment.
    Used as a car power supply, Power supply for laptop,PDA, or other digital products
    DIY a notebook mobile power
     
  10. DickCappels

    Moderator

    Aug 21, 2008
    2,653
    632
    The heatsink looks promising as does the power supply. Very good!

    Since this is not an established design expect to make some improvements as you go. From what I can see you have a good start.
     
  11. sscsksl

    Thread Starter New Member

    May 23, 2016
    8
    0
    I have been reading trying to understand more. I found this on Stack Exchange: Best practice is to control the current fed to a LED either by a series resistor (low power applications) or a switching current regulator (higher powers). This falls in line with your statement above on find a variable resistor that would safely handle the 3 amps.

    Question, would a switching current regulator serve me well to "trim" the intensity of the LED? I assume I would be looking for one that can safely handle 3 amps?
     
  12. DickCappels

    Moderator

    Aug 21, 2008
    2,653
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    Yes, that is the best way.
     
  13. sscsksl

    Thread Starter New Member

    May 23, 2016
    8
    0
    Thank you for your assistance. I feel like I have worn out my welcome so I will just keep this project simple.
     
  14. dannyf

    Well-Known Member

    Sep 13, 2015
    1,811
    362
    A smps can be easily modified to that.
     
  15. DickCappels

    Moderator

    Aug 21, 2008
    2,653
    632
    No, you have not worn out your welcome. You have come up with a solution to your problem.
     
  16. dannyf

    Well-Known Member

    Sep 13, 2015
    1,811
    362
    Here is what I meant earlier.

    What's within the red outline is a typical (adjustable) smps. It can be pretty much anything and the key here is that it attempts to adjust its voltage output so that it maintains a constant Vfb. That Vfb varies from module to module, based on the chips used. This particular chip I 'm using to demonstrate the principle has a Vfb of 2.2v.

    Normally, you adjust R2/R3 to vary the output voltage.

    To drive a led at a constant vurrent, all you need is a current sensing resistor R4, and your LEDs (D2/D3.....), and a connection from the middle of the two to Vfb -> within reason, R2/R3 values don't matter.

    The current through the leds, as shown in the simulation, is determined by Vfb / R4. In this case, it is 2.2v/22ohm = 100ma. Regardless of the input voltage (at least > 2.2v + Vfwd(d2..d3)), the smps will maintain that constant current.
     
  17. dannyf

    Well-Known Member

    Sep 13, 2015
    1,811
    362
    So if you wish to drive your leds at 0.5amp, using one of those el-cheapo ebay LM2596 modules (Vfb=1.1v), R4 = 1.1v/0.5 = 2.2ohm.

    the input voltage needed would be at least 1.1v + Vfwd for your leds.

    This is probably the best value LED drivers out there. Beats out building your own.

    Yes, I have done it myself many times.

    And the basic principle can be applied to pretty much any smps, as long as it operates to maintain a constant Vfb. obviously, the lower Vfb and lower power dissipation over R4.
     
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