Grove - Dust Sensor

Introduction


This Dust Sensor gives a good indication of the air quality in an environment by measuring the dust concentration. The Particulate Matter level (PM level) in the air is measured by counting the Low Pulse Occupancy time (LPO time) in given time unit. LPO time is proportional to PM concentration. This sensor can provide reliable data for air purifier systems; it is responsive to PM of diameter 1μm.

Note

  • This sensor uses counting method to measure dust concentration, not weighing method, and the unit is pcs/L or pcs/0.01cf.
  • Please pay attention to the warnings listed here.

Note

In the latest version, output Hi Voltage is changed from 4.0V to 4.5V.

Tip

More details about Grove modules please refer to Grove System

Specification


Item Norm Unit
VCC 4.75~5.75 V
Standby Current Supply 90 mA
Detectable range of concentration 0~28,000 / 0 ~ 8000 pcs/liter / pcs/0.01cf
Operating Temperature Range 0~45 °C
Output Method Negative Logic, Digital output, High: over 4.0V(Rev.2), Low: under 0.7V -
Detecting the particle diameter >1 μm
Dimensions 59(W) × 45(H) × 22(D) mm
Humidity Range 95% rh or less -

Platform Supported

Arduino
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Application Ideas


Getting Started

Cautions

  • Please keep it upright.
  • 3 min preheat time is required while using for the first time.
  • Arbitrary operation may cause unexpected damage.
  • Following widgets (red rectangle marked) is used only for the factory setting. Please DO NOT change the default configuration.

Grove - Help

Following documents help user get started with Grove. - Preface - Getting Started. - Introduction to Grove. - Getting Started on Windows - Getting Started on Mac OS X

Demos


Here is a demo to show how to obtain PM concentration data from this Grove - Dust Sensor.

1.Plug the dust sensor into digital port D8 on the Grove - Base Shield. It can only be D8 because the operation of this sensor involves sampling. This function only can be achieved by D8, the input capturing pin of ATmega328P, on Arduino/Seeeduino.

Also, you can connect Grove - Dust sensor to Arduino UNO without Base Shield: Arduino UNO |Dust Sensor –|– 5V| Red wire GND |Black wire D8| Yellow wire

2.Copy and paste the demo code below to a new Arduino sketch.

/*
Grove - Dust Sensor Demo v1.0
 Interface to Shinyei Model PPD42NS Particle Sensor
 Program by Christopher Nafis
 Written April 2012

 http://www.seeedstudio.com/depot/grove-dust-sensor-p-1050.html
 http://www.sca-shinyei.com/pdf/PPD42NS.pdf

 JST Pin 1 (Black Wire)  => //Arduino GND
 JST Pin 3 (Red wire)    => //Arduino 5VDC
 JST Pin 4 (Yellow wire) => //Arduino Digital Pin 8
 */

int pin = 8;
unsigned long duration;
unsigned long starttime;
unsigned long sampletime_ms = 2000;//sampe 30s ;
unsigned long lowpulseoccupancy = 0;
float ratio = 0;
float concentration = 0;

void setup() {
  Serial.begin(9600);
  pinMode(8,INPUT);
  starttime = millis();//get the current time;
}

void loop() {
  duration = pulseIn(pin, LOW);
  lowpulseoccupancy = lowpulseoccupancy+duration;

  if ((millis()-starttime) >= sampletime_ms)//if the sampel time = = 30s
  {
    ratio = lowpulseoccupancy/(sampletime_ms*10.0);  // Integer percentage 0=>100
    concentration = 1.1*pow(ratio,3)-3.8*pow(ratio,2)+520*ratio+0.62; // using spec sheet curve
    Serial.print("concentration = ");
    Serial.print(concentration);
    Serial.println(" pcs/0.01cf");
    Serial.println("\n");
    lowpulseoccupancy = 0;
    starttime = millis();
  }
}

In this program, the Seeeduino samples the total duration of “logic low” in 30s, and this duration illustrates the dust density of environment. Open Serial Monitor, we can get air quality’s value detected by sensor from PC’s serial port.

The result above consists of three parts: lowpulseoccupancy, ratio and concentration.

“lowpulseoccupancy” represents the Low Pulse Occupancy Time(LPO Time) detected in given 30s. Its unit is microseconds.

“ratio” reflects on which level LPO Time takes up the whole sample time.

“concentration” is a figure that has a physical meaning. It is calculated from the characteristic graph below by using the LPO time.

Here is a graph of the dust concentration measured in office :

We can see the concentration of dust is very low in the evening, but it is higher in the afternoon. A threshold can be set when the concentration is above a value. Also, if you want to set the sensor more sensitive you can add a fan on the sensor, and add a 10kΩ resistor between the Pin5 and Ground. More information please visit the blog of A.J.

Reference



If you want to make some awesome projects by Grove - Dust Sensor, here is a project for reference.

Air Quality Box

This section an IoT demo make by Seeeduino and Grove.

More attention is being paid to the environmental air quality nowadays because the tiny particles in the air around can badly endanger people’s health. We always get the information of environment from our government department. But it’s the average value of the whole city/section. It can not reflect the environment around you accurately.

Resources


Help us make it better

Thank you for choosing Seeed. A couple of months ago we initiated a project to improve our documentation system. What you are looking at now is the first edition of the new documentation system. Comparing to the old one, here is the progresses that we made:

  • Replaced the old documentation system with a new one that was developed from Mkdocs, a more widely used and cooler tool to develop documentation system.
  • Integrated the documentation system with our official website, now you can go to Bazaar and other section like Forum and Community more conveniently.
  • Reviewed and rewrote documents for hundreds of products for the system’s first edition, and will continue migrate documents from old wiki to the new one.

An easy-to-use instruction is as important as the product itself. We are expecting this new system will improve your experience when using Seeed’s products. However since this is the first edition, there are still many things need to improve, if you have any suggestions or findings, you are most welcome to submit the amended version as our contributor(Please refer to the tutotrial How to edit a document) or give us suggestions in the survey below, Please don’t forget to leave your email address so that we can reply.

Happy hacking