Product Specification Book
Product Name: | VOC Transmitter |
Product model: | MAQ15 |
Version: | V1.0 |
Formulator: | He Genwen |
Reviewer: | Yuan Chao |
Product Introduction
VOC Transmitter MAQ15 To use higher sensitivity air quality sensors to detect the current environment VOC Gas concentration.use RS485 Interface, standard MODBUS-RTU The protocol can realize multi-point synchronous monitoring, networking and transmit data from a long distance.Suitable for all kinds of places, especially for public places, factories, warehouses and other needs VOC Monitoring place.
To facilitate engineering networking and industrial applications, this module adopts widely used industrial MODBUS-RTU Communication protocol ，支持二次开发。用户 只需根据Communication protocol 即可使用任何串口通讯软件实现模块数据的查询和设置。
技术parameter
Serial number | parameter | Technical Indicators |
1 | Detect gas | Toluene, ethanol, H2S ， NH3 ， H2 wait |
2 | Protection level | IP65 |
3 | Measurement range | 0-500ppm |
4 | Resolution | 1ppm |
5 | Measurement error | ± 3%FS ( 25℃) |
6 | Response time | <6 minute |
7 | Output signal | Modbus RS485 |
8 | Power supply voltage | DC7V~36V |
9 | Operating temperature | -10℃ ~ 65℃ |
10 | Working humidity | 0-90%RH |
11 | Display method | none |
12 | Output load | RS485@120Ω |
13 | Installation method | Wall-mounted |
14 | weight | <300g |
15 | size | 117mm*87mm*51mm |
Wiring method:
As shown in the picture on the right, the device comes with a four-chip lead wire. The wiring is as follows:
The brown wire is the power supply positive.
The black wire is negative for power supply;
The yellow line is RS485+/A,
The blue line is RS485-/B
Notes:
1、Avoid exposure to silicone vapor.If silicone vapor is adsorbed on the surface of the sensor, the sensor's sensitive material will be encased, inhibiting the sensor's sensitivity and being unrecoverable.The sensor should avoid exposing it where silicon adhesives, hairsprays, silicone rubber, putty or other silicone-containing plastic additives may exist.
2、Avoid exposure to highly corrosive environments.Sensors are exposed to high concentrations of corrosive gases (like H2S ， SOX ，Cl2 ， HCl wait ) In this case, it will not only cause corrosion or damage to the heating material and sensor leads, but will also cause irreversible changes in the properties of sensitive materials.
3、Avoid exposure to alkali, alkali metal salts, and halogen pollution.
4、As VOC Testing is used in important working environments and must be tested regularly, usually within a cycle of 3 months to half a year to ensure that the sensor is correct. VOC sensitivity.
Communication protocol
All operation or reply commands of the device are hexadecimal data.Default communication baud rate: 9600, 8 N 1。
Basic format of sending command: Time interval: ≥50ms
xx | 03 | 00 | 00 | 00 | 01 | CRC_L | CRC_H |
Device address | Function code | Register address | Data length | CRC Check bit |
If you do not know the device address, 0 is available xFA It is a common query address.
That is, the command is: FA 03 00 00 00 02 D1 80
When the address is 1,
Read data command: 01 03 00 00 00 02 C4 0B
Return data: 01 03 04 00 15 00 00 CRC_L CRC_H
上述数据中： 01 表示地址 ，03 为读取命令Function code ，04 表示Data length 为 4 个字节 ， 由于测点Data length 占两个 字节 ，比如第 1 个数据为 00 15, 折成 10 进制即为： 21,即实际值为 21 PPM. In the configuration software, register comparison table:
Serial number | name | Register address | type | Value range |
1 | VOC Concentration Register | 00 00 | none 符号整型 | 0 ~ 1000 |
Change device address command:
When the device address is not known, the general address can be used FA：
That is, the command is: FA 06 0B 00 00 02 0A 2F，
Among them 02 is the address you want to modify.
06 为修改地址Function code
0B is an auxiliary command number.
00 00 is a fixed value and cannot be changed.
When the device address is 1, change to address is 2, and the command is as follows:
01 06 0B 00 00 02 0A 2F
The device response returns data: 02 25 01 02 90 06, that is, the address change is successful.
Note: The factory equipment address is 4 by default.
默认情况下串口parameter 为 9600 8 N 1 ， The number of bits of the stop bit can be modified through the command:
Function code 为 07 ，默认首地址为 04 ，修改命令如下
Use the current address to modify the stop bit to 1 bit: 04 07 00 00 00 00 00 B4 5F
Return data after successful setup: 04 07 01 00 B1 45
Use the current address to modify the stop bit to 2 bits: 04 07 00 00 00 01 75 9 F
Return data after successful setup: 04 07 01 01 70 85
Use the common address to modify the stop bit to 1: FA 07 00 00 00 00 A1 81
Return data after successful setup: FA 07 01 00 80 AD
Use the common address to modify the stop bit to 2 bits: FA 07 00 00 00 01 60 41
Return data after successful setup: FA 07 01 01 41 6D
Check the current number of serial port stop bits: 04 08 00 00 00 00 E0 5E
Return data: 04 08 01 xx CRCL CRCH
Use common address query: FA 08 00 00 00 00 F5 80
Return data: FA 08 01 xx CRCL CRCH
Returned xx When it is 00, the stop bit is 1 bit, and when it is 01, the stop bit is 2 bits.
