Portable luxmeter (Arduino + TSL2561)

[michalchoma]

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I decided to make luxmeter, which has basic functions:
1. measure lux from 0 to 188000 lux
2. calculate watts/m2
3. charging using USB cabel via TP4056 board

Basic sensor is MAX44009, which measure lux. I use Arduino Pro Mini as microcontroller.
Totally it cost cca 13 $. Case is homemade.
Power consumption - 15 mA.

for more info: https://www.instructables.com/id/Portable-Luxmeter/

BOM:
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BOM:
Arduino Pro Mini 5V
Link: **broken link removed**

MAX44009

0.045 Lux to 188,000 Lux Range
VCC = 1.7V to 3.6V
ICC = 0.65µA Operating Current
-40°C to +85°C Temperature Range
Link
https://www.aliexpress.com/item/328...&terminal_id=6f16b2047f114c94a07652c7f0a9951a

OLED display
Link: https://www.aliexpress.com/item/328...&terminal_id=6f16b2047f114c94a07652c7f0a9951a

Diagonal Screen Size：0.96"

Number of Pixels：128 x 64

Color Depth：Monochrome (Yellow&Blue)

Dimension：27.8 x27.3x 4.3 mm

Working Voltage: 3.3~ 5V DC

Power: 0.06W

MaxViewing Angle: >160 Degree

Duty：1/32Brightness ( cd/m2)：150 (Typ) @ 5V

Interface： I2C



TP4056
input 5V
Link: https://www.aliexpress.com/item/324...&terminal_id=6f16b2047f114c94a07652c7f0a9951a


Li-Ion battery

3 - 4.2 V
Link: https://www.aliexpress.com/item/328...&terminal_id=6f16b2047f114c94a07652c7f0a9951a

18650 holder
Link: **broken link removed**

Switch jumper
Link: **broken link removed**

Dupont cable a pin headers
Link: https://www.aliexpress.com/item/328...&terminal_id=6f16b2047f114c94a07652c7f0a9951a

pin headers
Link: https://www.aliexpress.com/item/326...&terminal_id=6f16b2047f114c94a07652c7f0a9951a


Circuit:
You need of course 5V Arduino to power it with Li-Ion battery (4,2 V!)

    // OLED display TWI address
    #define OLED_ADDR   0x3C
    Adafruit_SSD1306 display(-1); // restart display with reset button on arduino

    void setup()

    {

     Lux.Begin(0, 188000);
     display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR);
     display.clearDisplay();
     display.display();

     // display a line of text
      display.setTextSize(1);
      display.setTextColor(WHITE);
      display.setFont(&FreeSerif9pt7b);
      display.setCursor(1,15);
      display.print("MAX44009");
      display.display();
    }

    void loop()

    {
    lux=Lux.GetLux();  // get luxs
    watts =Lux.GetWpm();  // get watts/m2, only for SUN source

    display.fillRect(1, 20, 100, 100, BLACK); // create black rectangle on values position
    display.setCursor(1,40);
    display.print(lux);
    display.setCursor(80,40);
    display.print("lux");
    display.setCursor(1,60);
    display.print(watts);
    display.setCursor(80,60);
    display.print("W/m");
    display.setCursor(115,55);
    display.print("2");
    display.display();
    delay(1000);
    }

Photos:
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Charging

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Night pollution?

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[kripacharya]

Very nice.
I personally found the OLED module very difficult to mount, and extremely delicate. Also getting those larger fonts is a real pain.

Considering the small size of all these modules - I think the largest is your LiPo, you should try installing it in a smaller enclosure. Plastic ones are easier to work with. You don't really need that perf board.

Also your light sensor you should install behind some protective glass maybe.

What are the DIP switch for?

 

[michalchoma]

DIP switch if for turn on/turn off + charging on/off. Better should be desing own case, using 3D printer.
My light sensor I dont protective, because it will be less accurate. Only when not measuring, for protective from dust.
Do you like portable things?

 

[kripacharya]

DIP switch is a terrible selection for On/ Off control of anything other than occasional selection of optional features.

Good glass will not make your light sensor less accurate. After all, you are measuring visible light. Any diminishing of lux can be compensated for by calibration & software.

Next project you should make a colour meter.