product name： | Seven in one air quality detector |
Model： | MAQ01020406070914-S-P2 |
version： | V1.0 |
Creator： | He Genwen |
reviewed by： | Yuan Chao |
1、DESCRIPTION
The 7-in-1 air quality detector is a cost-effective digital signal output sensor product that adopts RS485 output mode, integrating CO2, formaldehyde, TVOC, laser dust PM2.5/PM10 particles, temperature, and humidity sensors. It can conduct real-time and comprehensive detection of the environment, with good stability and very convenient for customers to use.
2、application area
●Hotel room air quality monitoring
● Fresh air exchange system
● Air purifier, air conditioning
● Air quality monitoring equipment
● Kitchen and bathroom ventilation control system
● Smart home devices
3、Product features
● Simultaneously output seven sets of data including CO2, formaldehyde, TVOC, PM2.5, PM10, temperature, and humidity
● High sensitivity and stable data
● RS485 output
●Temperature resolution 0.1 ℃, humidity resolution 0.1% RH
● Output seven sets of sensor monitoring data through RS485 signal in the fastest 0.5 seconds
4、Range accuracy
Category | Measurement resolution | Measurement range | Measurement accuracy |
CO2 | 1ppm | 400ppm~5000ppm | ±50ppm+5%reading |
formaldehyde | 1ug/m3 | 0ug~1000ug/m³ | ±25% |
TVOC | 1ug/m3 | 0ug~2000ug/m³ | ±25% |
PM2.5 | 1ug/m3 | 0ug/m3~999ug/m³ | ±10% |
PM10 | 1ug/m3 | 0ug/m3~1000ug/m³ | ±10% |
temperature | 0.1℃ | -20℃~60℃ | ±0.5℃ |
humidity | 0.1%RH | 5~95%RH | ±5%RH |
5、Technical Parameter
connecting terminal | Communication: RJ45 interface, power supply: DC power port |
output signal | RS485 |
working voltage | 5.0±0.2VDC |
Average working current | ≤80mA |
Warm-up time | 2 minutes (formaldehyde and TVOC need to be preheated and stabilized, other parameters will be displayed when powered on) |
operation temperature | 0℃~50℃ |
Working humidity | ≤95％RH |
External dimensions | Diameter 168mm, height 51mm |
service life | 3 year |
6、interface definition
interface | name | function |
1 | RJ45 6th Foot of Mouth | RS485A |
2 | RJ45 8th Foot of Mouth | RS485B |
3 | Power hole | Connected to power supply 5VDC |
7、Appearance dimension diagram
8、note
Preheating for at least 2 minutes is required for initial power on use
Do not place the module in high concentration organic gases or corrosive gases for an extended period of time
Do not install the module for use in strong convective gas environments
To avoid large dust particles such as ground dust, floating debris, and even flocculent pollution that may cause fan winding and obstruction
Discussion on using equipment to adopt appropriate pre filtration treatment
Users should not disassemble sensors, including metal shielding shells, to prevent irreversible damage
This sensor is suitable for ordinary indoor environments
9、RS485 communication protocol
1、Overview of RS485 Communication Protocol
The communication protocol provides a detailed description of the input and output commands, information, and data of the seven in one air quality detector for third-party use and development.
Physical interface：
Connect the main communication port of the upper computer using a standard serial RS-485 communication port.
The information transmission method is asynchronous, with a start bit of 1 bit, a data bit of 8 bits, a stop bit of 1 bit, and no checksum. The default data transmission rate is 9600b/s
2、Detailed communication protocol
2.1 Communication methods
1) All loop communication should follow the master/slave mode. In this way, information and data are transmitted between a single master station and a slave station (monitoring device).
2) Support broadcast mode.
3) No matter what, communication cannot start from a slave station.
4) If the master station or any slave station receives a package containing unknown commands, the package will be ignored and the receiving station will not respond.
2．2 Return data frame structure description
The composition of each data frame is as follows: (RTU mode)
address
function code
data quantity
Data 1
...
Data n
CRC 16 bit check
3、transport format
1) Host sends read address command：
address | function code | Register address high bit | Register address low bit | Number of data high-order | Low order number of data | CRC 16 bit checksum |
00 | 03 | 01 | 00 | 00 | 01 | Xxxx Little Endian |
Slave return address：
address | function code | byte length | Address high bits | Address low bit | CRC 16 bit check |
00 | 03 | 02 | 00 | xx | Xxxx Little Endian |
Example: Sending：00 03 01 00 00 01 84 27
in response to：00 03 02 00 addr CRCL CRCH If addr=2, the sensor address read is 2
2) Host sends read data command：
address | function code | Data start address high bit | Data start address low bit | Return the high order of the number of data | Return the low order of the number of data | CRC 16 bit check |
xx | 03 | 00 | 02 | 00 | 07 | Little Endian |
( At present, only reading all data is supported, starting from address 0002, reading 7 data values. There are only 7 sensor data corresponding to 7 sensor addresses, and the high bit of the data starting address is always 0, while the high bit of the returned data is always 0 Internal message information
start address | Number of data | illustrate |
It can only be as follows: |
|
|
0x0002 | 1 | CO2 concentration |
0x0004 | 1 | Formaldehyde concentration |
0x0006 | 1 | TVOC concentration |
0x0008 | 1 | PM2.5 concentration |
0x000A | 1 | PM10 concentration |
0x000C | 1 | Temperature value |
0x000E | 1 | Temperature value |
The starting address can only use the addresses listed above, otherwise there will be no response. If the number of data exceeds, there will be no response. For example, if the starting address 0X000C, the number of data that can be returned can only be 1 or 2, and if 3 data are returned, there will be no response. Similarly, for address 0X000E, the number of data returned can only be 1. If the number of data returned is 0, there will be no response.
Slave sensor return value：
Slave address | function code | Number of data | data N | CRC |
XX | 03 | xx | xx | xxxx |
Byte length refers only to the length of data。
N0 | N1 | N2 | N3 | N4 | N5 | N6 | N7 | N8 | N9 | N10 | N11 | N12 | N13 |
CO2 high-order | CO2 Low position | formaldehyde high-order | formaldehyde Low position | TVOC high-order | TVOC Low position | PM2.5 high-order | PM2.5 Low position | PM10 high-order | PM10 Low position | temperature high-order | temperature Low position | temperature high-order | temperature high-order |
Example: Host sends 01 03 00 02 00 07 CRCL CRCH
Response：01 03 0E 02 26 00 26 00 34 00 0E 00 11 01 1C 02 5D CRCL CRCH
