Product manual

SPECIFICATION

• product name：	Carbon dioxide sensor
  Model：	MQC02-1
  version：	V1.0
  Creator：	He Genwen
  reviewed by：	Yuan Chao

   

  1、DESCRIPTION

  MQCO2-1 is a carbon dioxide sensor based on the principle of non spectral infrared absorption, which can detect the concentration of carbon dioxide in the air in real time. It has the characteristics of self calibration, small volume, superior performance, good consistency, and no oxygen dependence. This product has built-in temperature compensation and two communication methods: serial output and PWM output, making it convenient to use.

  

  This product is widely used in air quality detectors, air purification equipment, fresh air systems, air conditioning control, smart homes, IoT environmental information collection, agricultural production, cold chain transportation and other related fields.

   

  2、TECHNICAL INDEX

  Range range	400~5000ppm
  accuracy	± (50ppm+5%*reading)
  Interface	URAT_TTL(3.3V) PWM(3.3V)
  resolution ratio	1ppm
  response time	less than20s
  Data update time	4s
  Warm-up time	Less than 25 seconds (operable) Less than 2 minutes (90% accuracy) Less than 10 minutes (maximum accuracy)
  Supply Voltage	DC (5.0±0.5)V
  Working current	Average less than 70mA, peak less than 150mA
  working conditions	-10 ℃~+50 ℃, 0~95% RH, no condensation
  Storage conditions	-30~+70 ℃, 0~95% RH, no condensation
  Product Life	Over 5 years
  Product size	32.5mm×22.2mm×19.7mm(L*W*H)

   

   

  Pin Pitch

  2.54mm

   

  3、Appearance and structural dimensions

  

  32.5mm×22.2mm×19.7mm(L*W*H)，public errand±0.3mm

   

  4、interface definition

   

  

  Serial Number	name	describe
  1	NC	reserve
  2	RX	Serial port end (circuit board serial port receiving end)
  3	TX	Serial port end (circuit board serial port sending end)
  4	NC	reserve
  5	NC	reserve
  6	+5V	Power input terminal (+5V terminal)
  7	GND	Power input terminal (ground terminal)
  8	NC	reserve
  9	PWM	Pulse Width Modulation

   

  5、Serial communication protocol

  1．Serial port configuration: 9600 baud rate, 8 data bits, 1 stop bit, no parity check;

  2．How to receive host commands：

  1) Receive host commands：FE 04 00 03 00 01 D5 C5;

  Response response data: FE 04 02 01 E5 6D 3F; Among them, FE 04 02 represents the response data frame header, 01 E5 represents the carbon dioxide concentration of 485ppm, and 6D 3F represents the CRC verification data；

  2) Receive host commands：64 69 03 5E 4E;

  Response reply data：64 69 03 01 0A 02 00 00 00 00 00 00 9B F0; Among them, 64 69 03 01 represents the response data frame header, 0A 02 represents the carbon dioxide concentration, 02 is the high bit, 0A is the low bit, i.e. 20A, representing 522ppm, and 9B F0 is the CRC verification data;

  3)Receive host commands：11 01 01 ED

  Response response data: 16 05 01 02 06 00 00 00 DC; Among them, FE 16 05 01 represents the response data frame header, and 02 06 represents the carbon dioxide concentration of 518ppm;

  3．CRC calculation

  uint16_t CO2ModbusComm::modbus_calcuCRC(uint8_t *dataarray, uint16_t datalen)

  {

  uint8_t uchCRCHi = 0xFF ; /* CRC  High byte initialization of*/

  uint8_t uchCRCLo = 0xFF ; /* CRC  Low byte initialization of*/

  uint16_t uIndex ; /* CRC  Query Table Index*/

  uint16_t crc;

  const uint8_t auchCRCHi[] = {

  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81,

  0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,

  0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01,

  0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,

  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81,

  0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,

  0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01,

  0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,

  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81,

  0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,

  0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01,

  0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,

  0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81,

  0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,

  0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01,

  0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,

  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81,

  0x40

  };

  const uint8_t auchCRCLo[] = {

  0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2, 0xC6, 0x06, 0x07, 0xC7, 0x05, 0xC5, 0xC4,

  0x04, 0xCC, 0x0C, 0x0D, 0xCD, 0x0F, 0xCF, 0xCE, 0x0E, 0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09,

  0x08, 0xC8, 0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A, 0x1E, 0xDE, 0xDF, 0x1F, 0xDD,

  0x1D, 0x1C, 0xDC, 0x14, 0xD4, 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6, 0xD2, 0x12, 0x13, 0xD3,

  0x1 1, 0xD1, 0xD0, 0x10, 0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, 0xF2, 0x32, 0x36, 0xF6, 0xF7,

  0x37, 0xF5, 0x35, 0x34, 0xF4, 0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE, 0xFA, 0x3A,

  0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38, 0x28, 0xE8, 0xE9, 0x29, 0xEB, 0x2B, 0x2A, 0xEA, 0xEE,

  0x2E, 0x2F, 0xEF, 0x2D, 0xED, 0xEC, 0x2C, 0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26,

  0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0, 0xA0, 0x60, 0x61, 0xA1, 0x63, 0xA3, 0xA2,

  0x62, 0x66, 0xA6, 0xA7, 0x67, 0xA5, 0x65, 0x64, 0xA4, 0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F,

  0x6E, 0xAE, 0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68, 0x78, 0xB8, 0xB9, 0x79, 0xBB,

  0x7B, 0x7A, 0xBA, 0xBE, 0x7E, 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C, 0xB4, 0x74, 0x75, 0xB5,

  0x77, 0xB7, 0xB6, 0x76, 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, 0x70, 0xB0, 0x50, 0x90, 0x91,

  0x51, 0x93, 0x53, 0x52, 0x92, 0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54, 0x9C, 0x5C,

  0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E, 0x5A, 0x9A, 0x9B, 0x5B, 0x99, 0x59, 0x58, 0x98, 0x88,

  0x48, 0x49, 0x89, 0x4B, 0x8B, 0x8A, 0x4A, 0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C,

  0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86, 0x82, 0x42, 0x43, 0x83, 0x41, 0x81, 0x80,

  0x40

  };

  while (datalen--) /*  Complete the entire message buffer*/

  {

  uIndex = uchCRCLo ^ *dataarray++;/*  countCRC */

  uchCRCLo = uchCRCHi ^ auchCRCHi[uIndex];

  uchCRCHi = auchCRCLo[uIndex];

  }

  crc = (uint16_t)uchCRCHi *256;

  crc += (uint16_t)uchCRCLo;

  return crc;

   

  6、PWM calculation method

  cycle	1004ms±5%
  Mid cycle	1000ms±5%
  The calculation formula for obtaining the current CO2 concentration value through PWM is Cppm=5000 × (TH-2ms)/(TH+TL-4ms)
  Cppm  The calculated CO2 concentration value is measured in ppm TH The time when the output is at a high level in one output cycle TL The time when the output is at a low level in one output cycle

   

  7、note

   This product adopts NDIR technology, and the current required during the time when the light bulb is lit is relatively high. It is recommended that the power supply current be greater than 300mA.

• From a condensation state to a non condensation state, the system can return to normal operation within 2 hours.

• Please avoid vibration as much as possible. If subjected to vibration, dropping, or prolonged welding, it may result in a decrease in the measurement accuracy of the sensor. If severe vibration or drop occurs, the accuracy of the product needs to be verified.

• Do not use for a long time in environments with high dust density.

• Avoid long-term use in acidic, alkaline, and strongly oxidizing gas environments containing HF, H2S, SO2, HCL, NOX, NH3, PH3, CL2, F2, O3, H2O2, etc.

• Avoid applying external forces in any direction to the casing, as it may affect sensor performance and potentially cause damage

• Do not touch directly, make sure the operator wears an electrostatic discharge bracelet.

• The shell of this product is not grounded, and for applications with high ESD protection requirements, please contact the manufacturer's technical support