Infrared Carbon Dioxide Sensor Module CM1106SL

Transcription

1 Infrared Carbon Dioxide Sensor Module CM1106SL Application Ventilation system Central air-conditioning IAQ monitor Agricultural Planting, Plant growing Brief introduction Single Beam (Single light source, single wavelength) NDIR CM1106SL (Miniature size) can be used to detect CO2 concentration of indoor air by adopting advanced non-dispersive infrared technology (NDIR). It is widely used in IAQ monitor, air conditioner with purifying function, ventilation system, plant growing and other consumer electronic products etc. CM1106SL Specification Measurement range ppm default (0-5000ppm should be customized) Accuracy ± (50ppm+5% of reading) Working temperature -10 C ~+50 C Storage temperature -20~60 Working Humidity 0-95% RH(non-condensing) Main features Advanced non-dispersive infrared technology (NDIR) with independent intellectual property Temperature calibration within whole measurement range Small size and compact structure, easy to install Long life span, auto-calibration, maintenance free Storage Humidity Power supply Average current Signal output Size 0-95% RH(non-condensing) DC (5.0±0.25)V, Ripple wave<50mv measurement period UART_TTL 33*19.7*8.9mm Lifespan 10 years

2 Principle of measurement Molecule like CO2 and CO is composed of different types of atoms, it has absorption spectrum in infrared range. Absorption intensity abides by Lambert-Beer s Law. When light wave corresponded to certain gas with absorption spectrum passes through measured gas, the intensity of light wave will be significantly weakened. The intensity attenuation is related to concentration of measured gas. This relation follows Lambert-Beer s Law. Basic working principle of NDIR sensor is as below, Basic mathematical model:a majority of both organic and inorganic polyatomic gas have specific absorptive wavelength in infrared region. When infrared light passed by, the light transmissivity of this gas molecule to certain wavelength can be expressed by Lambert-Beer Law: Istands for light transmissivity, I=I 0 e -kpl i stands for light absorption intensity, i=i 0 -I= I 0 (1- e -kpl ) I 0 : incident light intensity. l: thickness of gaseous medium p: gas concentration k: absorption coefficient

3 I/O Definition CON5 CON4 No. Name Description No. Name Description 1 VCAP Light Source Power supply input (+5V) 1 VBB 2 RX UART-RX (Receiving) data, Compatible with 3.3V and 5V communication. 2 GND 3 TX UART-TX (Sending), Compatible with 3.3V and 5V communication. 3 RDY Power input enabled (+ 5 v power supply is 4 EN normal when in high level and disconnect in 4 P low level) 5 CAL Manual calibration MCU power supply input (+5V) Power supply input(gnd) Used to indicate that the sensor data is ready and the host could communicate (effective to low level output) MCU power supply input (+5V)

4 Circuit application case Case one: UART_TTL3.3v electrical level communication circuit Picture 3. UART_TTL 3.3V communication circuit reference Case Two: UART 3.3V electrical level transferred to 5V electrical level communication circuit Picture 4: UART 3.3V electrical level transferred to 5V electrical level communication circuit reference

5 Calibration Function Description Auto-calibration In the process of use, such as transportation, installation and welding operation may cause NDIR carbon dioxide sensor's drift and reduction of precision, so the sensor through the built-in auto-calibration algorithm to modify the drift. When the accumulative time of the sensor powered-on reaches 7 days, the sensor will record the lowest CO2 concentration data during these 7 days and perform auto-calibration to take this lowest CO2 concentration data as the zero point (400ppm). To ensure the accuracy of the sensor, please make sure the lowest CO2 concentration data during these 7 days could reach to close to outdoor atmospheric level (400ppm). Manual calibration In the process of use, such as transportation, installation and welding operation may cause NDIR carbon dioxide sensor's drift and reduction of precision. To quickly recover the accuracy of the sensor after installation, you can do manual calibration. Before manual calibration, please place the sensor in the environment which has same CO2 concentration level with outdoor atmospheric level (400ppm) and make sure the CO2concentration is stable. When performing manual calibration, pin CA side short circuit grounding for at least 2 seconds, the sensor will activate the calibration procedure after 6 seconds. In addition, the sensor can also activate the calibration procedure through software instruction, please refer to the communication protocol for more details.

6 Working Sequential Chart Note: Baud rate 9600 bd

7 Explanation of Working Mode Picture 4: The master-slave working mode (The sensor is the slaver) Note: If the sensor is always powered on, it will start a new 6 seconds working period per every 15 minutes. Average power consumptioncalculation If the sensor works every 15 minutes (900 seconds) by getting power from host and the calculation period plus communication period take 2 seconds. Then, 1. The average power consumption in 6s working period is 18mA 2. The average power consumption in 2s calculation and communication period is 5mA 3. The average power consumption in the rest time is 0.1μA. The average power consumption during 15 minutes period is I avg = (6*18* *5*1000+( ) *0. 1)/900 = 131μA

8 Dimensions Schematic diagram(tolerances: ±0.2mm) Dimension figure(error:±0.2mm)

9 Reliability test Test List Test Condition Standard Sample qty: N Defective qty: C Temperature influence curve Sensor powers on in the ambient of -10±2, 0±2, 10±2, 20±2, 30±2, 40±2, 50±2, to measure the error of sensor. Measuring error match temperature influence curve n=10 Low temperature storage. Leave the sensor in the ambient of -20±2 without power on, keep for 96 hours, detecting the measurement error of the sensor under normal temperature. The sensor works normally after 2 hours in the ambient of normal temperature n=5 Low temperature working Operating the sensor powered in the ambient of -10±2 for 96 hours, detecting the measurement error of the sensor in different CO2 concentration. The sensor works normally after 2 hours in the ambient of normal temperature n=5 High temperature storage. Leave the sensor(powered off) in the ambient of 60 ±2 for 96 hours. Then remove to the normal temperature and test the accuracy. The sensor works normally after 2 hours in the ambient of normal temperature n=5 High temperature working Operating the sensor with power on in the ambient of 50±2, after 96 hours, detecting the measurement error of the sensor in different CO2 concentration. The sensor works normally after 2 hours in the ambient of normal temperature n=5 Leave the sensor in ambient of -20 for 60 minutes, The sensor works normally and then move it to ambient of +60 within 10s, keep for the accuracy could meet the Thermal cycle another 60 minutes. Regard this as a cycle, and totally standard in the specification n=5 10 cycles Keep samples not powering on during the after 2 hours in normal test. temperature condition. High temperature, high humidity working(endurance test) Leave the sensor in the high temperature, high humidity ambient of 40±2,90%~95%RH, add the highest voltage within voltage working range. Keep for 500 hours. The sensor works normally and the accuracy could meet the standard in the specification after 2 hours in normal temperature condition. n=5 Salt spray test According to GB/T , leave the sensor in the 35 salt-fog cabinet, spray it with 5% sodium chloride saltwater for 24 hours. Clean the sensor after test. Recovery no less than 1 h but no more than 2 h in standard environment. No bad appearance. No corrosion. n=2 Vibration test Hz/min, with amplitude of 1.5mm, vibrate in X,Y,Z direction, each direction for 2 hours. No bad appearance after the test and the sensor could meet the basic performance test standard. n=4

10 Packaging drop test after the Package drop test Drop height: Set the height according to the regulations of the GB/T Test in accordance with the GB/T packaging transportation package drop test method. Drop test sequence: the corner, the triangular and six sides. sensor should be no bad appearance, no components, sensors should be able to work properly. No bad appearance after the package drop test. No component fall off and the n=1 sensor works normally.

11 Ordering information CM SL Derivative: SL Structure type 106:Structure number Product application 1:Civil class Product type CM:CO2 sensor

12 Packing Packing description Layer Carton Carton dimensions Packing material 18 layers 1080pcs W400 * L300 * H550 mm Red pearl cotton (ESD) After-sales services and consultancy TEL: FAX: ADD: Fenghuang No.3 Road,Fenghuang Industrial Park, Eastlake Hi-tech DevelopmentZone, Wuhan , China WEB: info@gassensor.com.cn