Temp. & humidity Transmitter Instructions

Transcription

1 Temp. & humidity Transmitter Instructions AQ3485/AQ3485Y

2 1 Product Overview AQ3485/ AQ3485Y outdoor network temperature and humidity transmitter is accurate measurement of relative humidity and temperature of an ideal solution for HVAC applications can be used in serious pollution of the environment, the transmitter selection of high-quality high-precision digital temperature and humidity sensor, with excellentlong-term stability, low delay, the ability of strong resistance to chemical pollution and a very excellent repeatability. Dimensions(Unit: mm) 2 Range of applications For the textile, food, scientific research, environmental protection, storage, weather stations (stations), workshops, factories, warehouses, libraries, offices, computer rooms, laboratories, greenhouses and other environmental temperature and humidity monitoring. 3 Features Appearance, digital calibration and long-term stability, full-range temperature compensation, temperature and humidity measurement range is wide, high and low temperature and humidity measurement accuracy. 4 roduct Selection Product ID Product Type DC voltage AC voltage Output Specification AQ3485 Outdoor 12~36V DC 12~24V AC 485 signal Conventional AQ3485Y Outdoor 12~36V DC 12~24V AC 485 signal LED Display - 1 -

3 5 Display LED products, the LED can directly display the temperature and humidity data, also shows some status information and error messages. Boot initialization Sensor error Normal display 6 Product parameters Relative humidity Range: 0 ~ 99.9% RH Accuracy (including non-linearity, hysteresis and repeatability): ± 2% RH Factory calibration uncertainty: ± 0.6% RH (0 ~ 40% RH) / ± 1.0% RH (40 ~ 97% RH) Response time (90%) still air at 8 s, the plastic grille Resolution: 0.1% RH Long-term stability: <0.5% RH / year Temperature Range (via jumper settings): -40 ~ 80 Accuracy: (25 ) ± 0.3 Resolution: 0.1 Long-term stability: <0.1 / year Work environment Operating temperature: AQ ~ 80 / AQ3485Y -20 ~ 70 Working environment humidity: 0 ~99.9% non-condensing Storage range Temperature: 0 ~ 60 Humidity: <90% RH Input and output Operating voltage: 12 ~ 36V DC (12 ~ 24V AC) Power-on time: 3s Temperature Output: 485 signal Humidity output: 485 signal Communication protocols: MODBUS RTU Note: The above parameters, such as no special instructions are at

4 7 Electrical connections Typical applications of data acquisition Connect the head of pin functions in the following table: Note: RS485 communication protocol, see the "communication protocol" Installation sequence 1. Will be the 4-cell (or shielded) to connect the cable transmitter side of the four lines were connected to the transmitter connector 1, 2, 3, 4 feet (with shielded cable shield connected to an electrical ground); 2.The other end of the corresponding access the power supply and computer (requires 485 converter) or other appropriate equipment; 3.The transmitter before and after the shell fastened; 4.After check the wiring is correct, prior to turning on the power, check the transmitter output is normal; 5.The transmitter can work properly. 8 Connected to the power If each transmitter uses a separate power to deal with the common ground for each transmitter.supply voltage temperature and humidity transmitter according to the connected load to allow the DC 12 ~ 36V range of power supply (less than 12V will enable the transmitter is not working properly, higher than 36V will cause transmitter damage), or AC power AC12 ~ 24V power supply within the range. 9 Connected to the testing equipment This transducer uses the RS485 communication, so it's testing equipment is computer. But other appropriate RS485 communication host, connected to the computer, such as the typical application shown, the computer serial port and transmitter need a RS232-RS485 converter, pay attention when connecting the A + and B-Do not connect error, connection error will cause the bus does not work - 3 -

5 properly when multiple transmitter cascade required drive capability and RS232-RS485 converter (recommended active type converter). Please carefully read the agreement of the transmitter connected to the RS485 communication host. Note 1: Connection error may lead to product damage. Note 2: Note the relationship of the ground between the testing equipment and transmitters. 10 Slave address and the baud rate settings The transmitter uses a common protocol, ModBus-RTU, the following settings are based on ModBus-RTU protocol. Baud Rate Setting RS485 to communicate, we must first determine the baud rate of the master and slave, not the same baud rate will lead to the communication is unsuccessful. Open the transmitter from the back cover, you can see there are two sets of switches on the transmitter PCB, in which a group is two DIP switches (see internal note section of the 1.5 product structure) is the baud rate setting switch. Switch status and baud rate corresponding to the following table: 11 Slave address settings ModBus-RTU protocol, each terminal has an address, eight DIP switch PCB board (see 1.5 product structure, internal notes section) to set the communication address, eight allows up to 255equipment (address from 1 to 255) to the system. For the corresponding position of a DIP switch to ON and the OFF set to 0. In this system, when the address switch to select 0 ( ) (this way is not recommended), default slave address 1 as follows in Figure 1 shown below: Address = 1 ( ) address = 2 ( ) Address = 13 (00,001,101) Other address set to follow the 8-bit binary code corresponds to the relationship, as (2,3,4) Note: in the choice of measurement range jumper operation, turn off the transmitter power. 12 Communication protocol Communicate Baud rate Data bits Stop bits Parity bits Value Optional settings MODBus Communication parameters - 4 -

6 Host command frame format Slave response frame format Note 1: The register number of the two bytes 0X0002 representatives in the above example reads the value of the two 16-bit registers, host the meaning of the command frame: command device 01 to send two 16-bit data to the host to startaddress high starting address is not defined in this Agreement, the default value of 0x00, 0x00. Note 2: 01 (address) equipment to respond to host four bytes of data sent to the host, which contains the humidity data of the two-byte, 2 bytes of temperature data. 13 Numerical calculation Divided by 10 to the value returned from the machine, corresponding to the temperature units ( ), corresponding to the humidity unit (RH%). Such as the return from the machine humidity value 0x02B1, 0x02B1 converted to decimal derived value 689, and then use the value of is the desired humidity value is 68.9 (% RH). 14 Error checking code (CRC checksum) Master or slave can be used the checksum discriminant receive information is correct. Due to electronic noise or other interference, the information in the transmission process, sometimes an error occurs, the error checking code (CRC) can verify that the host or slave in the communication data transfer process the information is incorrect, erroneous data can give up (whether to send or receive), thus increasing the safety and efficiency of the system

7 ModBus communication data CRC (redundant cyclic code) consists of two bytes, 16-bit binary number. CRC code calculated by the sending device, placed on the tail of the send a message. The device receiving the information re-calculate the received CRC of the information, compare the calculated CRC is consistent with the received, if they do not match, it indicates an error. During the CRC calculation, only 8 data bits, start bit, stop bit and parity bit are not involved in the CRC calculation. CRC code calculation method 1. Preset 16-bit register 12 hexadecimal 0xFFFF (all 1); call this register for the CRC register; 2. An 8-bit binary number (ie, communications and information the first byte of the frame) and 16-bit CRC register eight different or results in the CRC register; 3. To fill the highest bit CRC register content shifted to the right a (DPRK low) 0, and check out of the bit shifted to the right after; 4. Out of bit 0: repeat the third step (once again shifted to the right one); out of bit 1: CRC register with the polynomial 0xA001 ( ) XOR; 5. Repeat steps 3 and 4, until shifted to the right 8 times 8, so that all the data processing; 6. Repeat steps 2 through 5, communications and information processing of the frame the next byte; 7. The communication all bytes of the frame calculated by the above steps are finished. The end of the CRC register content is: CRC code. CRC checksum algorithm C program unsigned short crc16(unsigned char *ptr, unsigned char len) unsigned short crc=0xffff; unsigned char i; while(len--) crc ^=*ptr++; for(i=0;i<8;i++) if(crc & 0x01) crc>>=1; crc^=0xa001; else crc>>=1; return crc; * Note: This program calculates the CRC code, * ptr, len length bytes - 6 -

8 15 Errors and sources Humidity varies with temperature error maps Temperature error map The measured value of the product may be subject to the following factors: 1. the temperature error placed in a test environment in settling time is too short. near sources of heat, cold source, or directly at the sun. 2.the humidity error placed in a test environment in settling time is too short. prohibited for a long time in the steam, spray, curtain or condensing environments. 3.pollution dust or other environmental pollution, regular cleaning of the product

9 16. License Agreement Without the prior written permission of the copyright holder, shall not in any form or by any means, electronic or mechanical (including photocopying), copy any part of this manual, nor shall its contents be communicated to a third party. The contents are subject to change without notice. Aosong Electronics Co., Ltd. and third-party ownership of the software, the user may use only signed a contract or software license. 17. Warnings, and personal injury This product is not applied to the safety or emergency stop devices, as well as the failure of the product may result in injury to any other application. Shall not apply this product unless there is a special purpose license. Installation, handling, use or maintenance of the product refer to product data sheets and application notes. Failure to comply with this recommendation may result in death and serious personal injury. The Company will bear the resulting personal injury and death compensation, and waive any claims that the resulting subsidiary company managers and employees and agents, distributors, etc. that may arise, including: a variety of costs, compensation costs, attorneys' fees, and so on. 18. Quality Assurance Their products directly to buyers to provide quality assurance for a period of 12 months (one year) (calculated from the date of shipment). Publishes the technical specifications of the product data sheet shall prevail. If the warranty period, the products are card quality is defective, the company will provide free repair or replacement. The user must satisfy the following conditions: 1 The product is found defective within 14 days written notice to the Company; 2 The return to the company should be paid by the purchaser; 3 The product should be within the warranty period. The Company is only responsible for those used in the occasion of the technical condition of the product defective product. Without any guarantee, warranty or written statement of its products used in special applications. Company for its products applied to the reliability of the product or circuit does not make any commitment