MULTIFUNCTION AIR QUALITY SENSOR MODULE (MODBUS)
User Guide for SRAQ-D701
Tlhaloso ea Sehlahisoa
The SRAQ-D701 is a comprehensive air quality sensor module which combines CO², laser dust, temperature and humidity, TVOC and formaldehyde.
Developed for integration into air purifiers, air quality monitors and custom enclosures. The SRAQ-D701 provides real time concentration values via Modbus-RTU output. It offer good stability, and is well suited for applications where TVOC and particulate matter concentrations are a concern.
Likaroloana
- Detects multiple pollutants CO2, dust etc.
- Tlhahiso ea Modbus
- High reliability and good stability
- High accuracy & fast response
- Compact design for easy integration
Lisebelisoa
- Office and commercial buildings
- Factory floors
- Lilaboratori
- HAVC industry
- General air quality monitoring
- Litsamaiso tse bohlale tsa lapeng
Thank you for choosing L-com product. To ensure safe, accurate performance and product longevity, please take a moment to familiarize yourself with this manual before powering the device. Please keep it handy for future reference. In case of any questions regarding the installation or use of product, please call us at 800.341.5266.
Ikopanye le rona ho customerservice@l-com.com le ho etela rona website at www.l-com.com
This datasheet has been downloaded from http://www.digchip.com at this leqephe
Tekheniki Parameters
Detection Parameters and Resolution: The CO2 value and formaldehyde value measured by the module are equivalent value of TVOC, please pay attention when using or purchasing.
| Se silafatsang | Qeto ea tekanyo | Lekhalo la ho lekanya | Ho nepahala |
| eCO2 | 1 ppm | 400 ~ 5000 ppm | ± 100 ppm |
| PM2.5 | 0.3 ug/m3 | 0~1000 ug/m3 | ± 10% |
| PM10 | 0.3 ug/m3 | 0~1000 ug/m3 | ± 10% |
| Mocheso | 0.01 °C | 20 ~ 80 ° C | ± 0.5 °C |
| Mongobo | 0.04% | 5 ~ 100% RH | ± 3% RH |
| TVOC | 1 ug/m3 | 1230 ug/m3 | ± 90 ug/m3 |
| CH2O | 1 ug/m3 | 500 ug/m3 | ± 40 ug/m3 |
- Sebetsa voltage: 5 ± 0.2 VDC
- Working environment: Working temperature 0~50 °C, Working humidity: 15% RH 90% RH (no condensation)
- Working environment: Temperature range -20~60 °C, Humidity: 5% RH 95% RH (no condensation)
- Communication method: Modbus RTU RS485
- Preheating time: 10-15 minutes, the longer the power-on time, the more stable the data will be.
Lithahasello tsa ho phahamisa
Mounting type: Board mount. Hole diameter 2 mm, pitch 11.5 mm.
Mohala Tlhaloso
Port connector type is XH2.54mm pitch 4-pin terminal connector, 90° vertical mounted to PCB.
| Sr. No. | Mosebetsi | Lintlha | Mmala |
| 1 | VCC | 12 – 24 VDC, power supply positive | Brown |
| 2 | GND | GND, power supply negative | Ntsho |
| 3 | RS485_A+ | RS485_A+ | Botala |
| 4 | RS485_B- | RS485_B- | Boputsoa |
Puisano Protocol
The module hardware supports serial TTL communication interface and RS485 communication interface. When testing, users need to choose the corresponding communication method development according to the module interface type they have purchased.
RS485 Interface Communication Interface Related Protocol:
Serial port parameters: (9600/8/N/1) Mod Bus-RTU 485
The factory default address of the module is 0x01
Baud rate: 9600, Check bit: no, Stop position: 1 bit
Return data time: <300ms
The reading speed cannot exceed 350ms
Read Address Command
| Amohela | E tsitsitse | Khoutu ea Mosebetsi | E tsitsitse | E tsitsitse | E tsitsitse | E tsitsitse | CRC_L | CRC_H |
| FE | 17 | 00 | 00 | 00 | 01 | Tlhahlobo ea CRC | ||
| Araba | E tsitsitse | Khoutu ea Mosebetsi | Palo ea li-Byte | Mofuta oa Firmware | Aterese ea Hona Joale | CRC_L | CRC_H | - |
| FE | 17 | 02 | xx | yy | Tlhahlobo ea CRC | - | ||
Bakeng sa mohlalaample: Send command: FE 17 00 00 00 01 A0 06 Return data: FE 17 02 11 01 64 30
Indicates that the device address is 01 and the version number is V1.1
Modify Address Command
The factory default address of the module is 0x01, and the address range can be changed to: 0~254.
| Amohela | Aterese ea Hona Joale | Khoutu ea Mosebetsi | E tsitsitse | E tsitsitse | Reserved | Aterese ea kamehla | CRC_L | CRC_H |
| yy | 06 | 00 | 00 | 00 | zz | CRC hlahloba | ||
| Araba | Address Before Modification | Khoutu ea Mosebetsi | Palo ea li-Byte | Boloka | Modified Address | CRC_L | CRC_H | - |
| yy | 06 | 02 | 00 | Zz | CRC hlahloba | - | ||
Bakeng sa mohlalaample: When the current address is 01, the preset address is: 02
Send command: 01 06 00 00 00 02 08 0B Return data: 01 06 02 00 02 39 49
Read Data Command
| Amohela | Aterese ea Hona Joale | Khoutu ea Mosebetsi | Ngolisa Aterese ea ho Qala | Number of Sensors Required to Read | CRC_L | CRC_H | ||
| yy | 03 | 00 | MM | 00 | NN | CRC hlahloba | ||
| Araba | Aterese ea Hona Joale | Khoutu ea Mosebetsi | Bolelele ba Ditaba | Lintlha tsa Sensor | CRC_L | CRC_H | - | |
| yy | 03 | NN*2 | xx xx ……xx xx | Tlhahlobo ea CRC | - | |||
Note: The returned xx xx ……xx xx sensor data can be changed according to the register address and data length.
00 MM represents the register address of the sensor, and 00 NN is the data length.
| Register address（00 MM） | ||||||
| 00 00 | 00 01 | 00 02 | 00 03 | 00 04 | 00 05 | 00 06 |
| eCO2 | TVOC | CH2O | PM2.5 | Mongobo | Mocheso | PM10 |
Tlhaloso
- The minimum number of sensors 00 NN is 00 01, and the maximum is 00 07. When the MM value is 00, the maximum NN value can be 07. At this time, the value of all sensors can be read, and it can also be 01. When it is 01, only CO2 data can be read alone. And so on.
- The address at the front of the register can read the data of the following sensor when the data length is increased, but the address at the back of the register cannot read the data of the sensor before this address. See details below:
| 00 MM 00 NN | Environmental data that can be read |
| 00 00 00 01 | Indicates that CO2 data is read from the starting address 00 00 |
| 00 00 00 02 | Means to read CO2, TVOC data from the starting address 00 00 |
| 00 00 00 03 | Means to read CO2, TVOC, CH2O data from the starting address 00 00 |
| 00 00 00 04 | Means to read CO2, TVOC, CH2O, PM2.5 data from the starting address 00 00 |
| 00 00 00 05 | Means to read CO2, TVOC, CH2O, PM2.5, H data from the starting address 00 00 |
| 00 00 00 06 | Means to read CO2, TVOC, CH2O, PM2.5, H, T data from the starting address 00 00 |
| 00 00 00 07 | Means to read CO2, TVOC, CH2O, PM2.5, H, T, PM10 data from the starting address 00 00 |
| 00 01 00 01 | Indicates that the TVOC data is read from the starting address 00 01 |
| 00 01 00 02 | Indicates that TVOC and CH2O data are read from the starting address 00 01 |
| 00 01 00 03 | Means to read TVOC, CH2O, PM2.5 data from the starting address 00 01 |
| 00 01 00 04 | Means to read TVOC, CH2O, PM2.5, H data from the starting address 00 01 |
| 00 01 00 05 | Means to read TVOC, CH2O, PM2.5, H, T data from the starting address 00 01 |
| 00 01 00 06 | Means to read TVOC, CH2O, PM2.5, H, T, PM10 data from the starting address 00 01 |
| 00 02 00 01 | Indicates that CH2O data is read from the starting address 00 02 |
| 00 02 00 02 | Indicates that CH2O and PM2.5 data are read from the starting address 00 02 |
| 00 02 00 03 | Means to read CH2O, PM2.5, H data from the starting address 00 02 |
| 00 02 00 04 | Means to read CH2O, PM2.5, H, T data from the starting address 00 02 |
| 00 02 00 05 | Means to read CH2O, PM2.5, H, T, PM10 data from the starting address 00 02 |
| 00 03 00 01 | Indicates that PM2.5 data is read from the starting address 00 03 |
| 00 03 00 02 | Means to read PM2.5, H data from the starting address 00 03 |
| 00 03 00 03 | Means to read PM2.5, H, T data from the starting address 00 03 |
| 00 03 00 04 | Means to read PM2.5, H, T, PM10 data from the starting address 00 03 |
| 00 04 00 01 | Indicates that the H data is read from the starting address 00 04 |
| 00 04 00 02 | Means to read H, T data from the starting address 00 04 |
| 00 04 00 03 | Means to read H, T, PM10 data from the starting address 00 04 |
| 00 05 00 01 | Indicates that the T data is read from the starting address 00 05 |
| 00 05 00 02 | Means to read T, PM10 data from the starting address 00 05 |
| 00 06 00 01 | Indicates that PM10 data is read from the start address 00 06 |
How to Read a Frame of Data
Bakeng sa mohlalaample, if the address of the module is 0x01, the user needs to send 01 03 00 00 00 07 04 08 to read out seven kinds of sensor data.
The returned data format is as follows:
| Byte[0] | Byte[1] | Byte[2] | Byte[3] | Byte[4] | Byte[5] | Byte[6] | Byte[7] | Byte[8] | - |
| Hlooho | Khoutu ea Mosebetsi | Bolelele ba Ditaba | CO2 Lintlha | TVOC Data | CH2O Data | - | |||
| 0x01 | 0x03 | 0x0E | CO2_H | CO2_L | TVOC_H | TVOC_L | CH2O_H | CH2O_L | - |
| Byte[9] | Byte[10] | Byte[11] | Byte[12] | Byte[13] | Byte[14] | Byte[15] | Byte[16] | Byte[17] | Byte[18] |
| Lintlha tsa PM2.5 | Lintlha tsa Mongobo | Lintlha tsa Mocheso | Lintlha tsa PM10 | Setšoantšo sa CRC16 | |||||
| PM2.5_H | PM2.5_L | Hum_H | Hum_L | Tem_H | Tem_L | PM10_H | PM10_L | CRC16_L | CRC16_H |
Calculation Method of Each Sensor Data
CO2 (ppm) = CO2 _H * 256 + CO2 _L
TVOC(ug/m3) = (TVOC_H * 256 + TVOC_L) / 10
CH2O(ug/m3) = (CH2O_H * 256 + CH2O_L) / 10
PM2.5 (ug/m3) = PM2.5_H * 256 + PM2.5_L
PM10 (ug/m3) = PM10_H * 256 + PM10_L
Positive temperature (°C) = (Temperature _H * 256 + Temperature_ L) / 10
Bakeng sa mohlalaample: T = (0 x 0110) / 10 = 272 / 10 = 27.2 ℃
Negative Temperature (°C)
Method 1: Directly convert to a signed int type, for example: T = 0 x ffbf / 10 = -65 / 10 = -6.5 ℃
Method 2: If greater than 0 x 7fff (32767)
Then it is a negative number T = (0 x ffbf – 65536) / 10 = (65471 – 65536) / 10 = -65 / 10 = -6.5 ℃
Humidity (%RH) = (Humidity _H * 256 + Humidity _L) / 10
Bakeng sa mohlalaample: T = (0 x 02AD) / 10 = 685 / 10 = 68.5 %RH
Note: If user need to use mg/m3 as the unit, please convert it. The conversion formula is: 1mg/m3 =1000 ug/m3
The length of the CRC check byte is 17 (that is, the bytes of Byte[0]~Byte[16]), select A001 or 8005 in reverse order.
Litaba Tse Lokelang ho Eloa Hloko
- Avoid contact with organic solvents (including silica gel and other adhesives), paints, pharmaceuticals, oils and high-concentration gases.
- The module must not be subjected to excessive shock or vibration.
- Se ke oa sebelisa mojule ona litsamaisong tse amanang le polokeho ea motho.
- Se ke oa kenya module sebakeng se matla sa moea oa convection.
CRC Check Calculation Method
Function function: CRC check function, generate CRC
Parameter description: arr_ buff: array set to be verified
len: The length of the data to be verified
Return parameter: CRC is an unsigned int type, the high byte is the high byte in front, and the low byte is in the back unsigned int CRC_ Compute ( unsigned char *arr_ buff, unsigned char len)
{
unsigned int crc=0xFFFF;
char e saennoang i, j;
for ( j=0; j <len;j++)
{
crc=crc ^*arr_buff++;
for ( i=0; i<8; i++)
{
if( ( crc&0x0001) >0)
{
crc=crc>>1;
crc=crc^ 0xa001;
}
tse ling
crc=crc>>1;
}
}
return ( crc);
}
Litokomane / Lisebelisoa
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L-com SRAQ-D701 Multifunction Air Quality Sensor Module [pdf] Bukana ea Mosebelisi SRAQ-D701, SRAQ-D701 Multifunction Air Quality Sensor Module, Multifunction Air Quality Sensor Module, Air Quality Sensor Module, Sensor Module |