RoHS. CO 2, Temperature & Humidity Transmitter Applications

Transcription

1 NDIR CO 2 Dual sensor Needless calibration on long-term use Can measure over 95% RH condition Applicable to humid storage, mushroom farm and floricultural industry Communication Method RS-485 (Standard) 4~20 ma (Option) 0~5 V analog (Option) RoHS CO 2, Temperature & Humidity Transmitter Applications - Ventilation Control - Heat Ventilation Air Conditioning System - Mushroom Farming Greenhouse - Greenhouse and Humid Storage - Floricultural Industry - Cold storage, vegetable storage SOHA TECH CO,.Ltd. Suite 104, Hagye technotown A,250-3, Hagye-dong,Nowon-gu,Seoul, Korea TEL : ,2,5 FAX : This product can be changed for quality improvement without notification

2 Features Input Power : DC 12 ~ 24 V, over 200 ma Power consumption: Normal 40 ma, Peak 135 ma Model: SH-VT250 = RS-485 Communication SH-VT250A = 4 ~20 ma output type SH-VT250V = 0 ~ 5 V output type CO 2 (Carbon Dioxide), Temperature, Humidity Transmitter Analog output tupy : 4~20 ma Current Loop (option) : 0~5V (0ption) Communication output: RS485 Precision Temperature and Humidity sensor Can be connected with PLC or MICOM controller Suitable for humid and weeping water condition Low Cost, High Quality IP65 Protection grade - 2 -

3 CAUTION Cautions for the installation of SH-VT250 You have to install SH-VT250 in the direction of O mark. And don t turn the power off when using SH-VT250. It causes dampness inside the product. In case of turn the power off, you have to store this product in non-condensing condition. When user spray agricultural pesticides, VT250 transmitter should be covered with plastic bag - 3 -

4 SPECIFICATIONS CO 2 sensor List Contents Remarks Measuring method NDIR Measuring Range 0~3000/5000/10,000 ppm option Accuracy Response time 0 ~ 80% < 30 Sec Signal update term Every 2.0 Seconds Warm-up < Working Temp 0 ~ 50 ( -10~50 Option) Working Humidity 0 ~ 99.9% RH Temperature sensor List Contents Remarks Measuring Range -25 ~ 85 (RS485) -10 ~ 50 (Analog) Accuracy ±0.3 Response Time 5 ~ 30 sec SH-VT250 SH-VT250A Max. ±0.4. Humidity sensor List Contents Remarks Measuring Range 0 ~ 99.9 %RH Accuracy ±2 %RH Response time 8 sec - 4 -

5 Communication Protocol 1. Data Transmission Format Byte Contents STX ID CO2 Value Temperature Value Byte Contents Humidity Value SHT Mode Check Sum CR LF Each content is displayed by ASCII type - STX: Start Code (0x02) - ID: Transmitter ID (Initial value : 0x00) - CO 2 Value: a number of four byte ASCII cords - Temperature Value Display Below zero, 9 th Byte is - (0x2D) Above zero, 9 th Byte is Space(0x20) 12 th Byte decimal point display is. (0x2E) - Humidity Value Display 17 th Byte decimal point display is. (0x2E) - SHT: display condition of temperature and humidity sensors 0 (0x30) = normal running 1 (0x31) = measured temp. & humidity value error Or temp. & humidity sensor connection error (temp. & humidity data will be displayed former one) - Mode: 0 (0x30) = data transmission every 2 sec 1 (0x31) = data transmission when DTE needs data (Initial value : 0x30) - Check Sum: Sum of 1~21Byte, use low data 1Byte only - CR: 0x0D - LF: 0x0A - 3, 8, 14, 19 Byte: Space (0x20) ** Compare the Check Sum after receiving 24 Byte and check the error. ** If the value of SHT is 1, the measured temp. & humidity values are error. Or the connection wire of temp. & humidity has problems. In this case, transmitted data is former measured data - 5 -

6 2. Set up Byte Contents STX ID S Set ID Mode Reserve Check Sum CR LF - STX: Start Code (0x02) - ID: Transmitter ID ( if this byte set as 0x00 :every transmitter accepts command) - S (0x53): set up Command - Set ID: Transmitter ID set(0x00 ~ 0xFF) - Mode: 0 (0x30) = data transmission every 2 sec 1 (0x31) = data transmission only when controller request data (Initial value : 0x30) - Reserve - Check Sum: Sum of 1~7Byte, use low data 1Byte only - CR: 0x0D - LF: 0x0A ** If user want to set Transmitter s ID, don t use 0x00. ( ID 0x00 has reserved as automatic transmission) If transmitter has set as some of specific ID except 0x00, it will respond automatically when transmitter receive 0x00 Call. This function allow you to set up transmitter, even if you don t know the ID. ** Notice : When many transmitter connected in parallel, if controller call ID 0x00, every transmitter will respond

7 3. Data Command (Mode 1 only) Byte Contents STX ID R Reserve Check Sum CR LF - STX: Start Code (0x02) - ID: Terminal ID - R (0x52): Data request Command - ID set: Terminal ID set (0x00 ~ 0xFF) - Reserve - Check Sum: Sum of 1~7 Byte, use low data 1 Byte only - CR: 0x0D - LF: 0x0A Modbus protocol Modbus Address Map Hex Address Dec contents (2 byte) read /write 0x CO2 Value Read 0x Temperature Value Read 0x Humidity Value Read 0x6A 106 Temp. RH sensor error status 0x00 0x30 : Normal 0x00 0x31 : Error 0x6C 108 Device ID read read/write (Refer to additional description) Notice: measured values of temperature and humidity must be divided by 10 before use the data. Ex) Read Value 253(0x00FD) -> Real Value 25.3, Read Value -123(0xFF85) -> Read Value -12.3, - 7 -

8 When user apply Device ID writing instruction, DIP switch should be set as 1 before sending instruction. ID writing sequences are like bellows, 1. Turn off the power. 2. Set Dip S/W as Switch on the power. 4. Write Device ID. 5. Turn off the power again. 6. Set Dip S/W as F (1111). 7. Switch on the power again. 8. Device is ready to communicate as a set ID. [DIP S/W 1 (only No. 4 pin ON(UP)) - 8 -

9 Dip Switch setting method Data transmission every 2 sec ID 1 Setting, Data transmission when DTE needs data ID 2 Setting, Data transmission when DTE needs data ID 3 Setting, Data transmission when DTE needs data ID 14 Setting, Data transmission when DTE needs data When use ID(15 ~ 255) of which Serial communication set up * Note: When DIP switch value is 0 (all dip switch are Off), serial communication setup is not available. Other dip switch setting except 0 are available of serial communication. Before set ID and apply new setting, power should be off. Ex) 1) Turn off the power 2) set dip switch (ID) 3) Switch on the power Select output mode (SH-VT250A only) output OFF 0~5V output output OFF 4~20mA output - 9 -

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12 Analog wiring diagram

13 Dimension