[technology development] development and design of alcohol tester solution

　　 Today, China's economy is developing at a high speed , People's living standards are constantly improving , All kinds of motor vehicles have become an indispensable part of people's life . Especially the appearance of private cars , Undoubtedly, it will greatly improve the efficiency of people's life and work , But the problems brought about by it also follow , This is the question of safety . Many years ago, traffic controllers could only judge whether drivers drank alcohol subjectively 、 The naked eye observation and go to the hospital to test the alcohol content in the blood , These unscientific and untimely methods have caused many unnecessary misunderstandings and troubles . The above problems are due to the lack of portable, safe and accurate online alcohol concentration detection instruments . In this scheme, the ethanol gas sensor with low power consumption is used as the sensitive unit , Convert the gaseous concentration of ethanol contained in the gas into an electrical signal , the A/D The conversion circuit is sent to the single chip microcomputer for processing , The concentration of ethanol in the measured gas is visually displayed by the digital tube , At the same time, judge whether to send voice alarm signal according to specific conditions .

　　LCD Function introduction of alcohol tester

　　1. Turn it on ： Press and hold the key 2 Second power on , Buzzer “ di ” A sound ,LCD Full display 1 second .

　　2. preheating ： Buzzer “ di ” A sound , Start 10 Seconds to warm up , Show at the same time ① Warm up sign ② battery level ③ Sensor life indicator ④10 Seconds down ji Time display ⑤ arc .

　　3. measurement ： Buzzer “ di ” A sound , Start 10 Second measurement , Show at the same time ① Blowing sign ② battery level ③ Sensor life indicator ④10 Seconds down ji Time display ⑤ arc .

　　4. result ： Buzzer “ di ” A sound , Start 10 The second result shows , Show at the same time ① Result flag ② battery level ③ Sensor life indicator ④ Measurement value and unit ⑤ arc ⑥ Warning level sign , The buzzer will sound when the result is out of range “ Diddiddidi ” Continuous alarm ; Press and hold the key in this state 2 Seconds to enter the history display .

　　5. Historical record ： Buzzer “ di ” A sound , Display record number 1 second （1~50）, Then the history and units are displayed 9 second , Show at the same time ① Result flag ② battery level ③ Sensor life indicator ④ Warning level sign ; In this state , Short press the key to record the number increasing circularly , And restart the display ji when ; In this state, the arc around the value is not displayed .

　　6. To turn it off ： Buzzer “ di ” A sound , Display the sensor life indicator 1 Seconds later , The screen is turned off .

　　 Sensor life indicator

　　1. Number of tests ≤500 when , green

　　2. Number of tests ＞500 And ≤1000 when , yellow

　　3. Number of tests ＞1000 when , Red

　　4. Number of tests ＞2000 when , Flashing red

　　5. Number of tests ＞2500 when , Jump straight to 【 To turn it off 】

　　 battery level

　　1. Battery voltage ≥3.7V when , The battery logo is displayed in full cells

　　2. Battery voltage 3.3V~3.6V when , The battery logo is displayed in half space

　　3. Battery voltage 3.2V when , The battery flag space displays

　　4. Battery voltage 3.1V when , The battery flag space flashes

　　5. Battery voltage 3.0V when , The battery flag space flashes , Jump straight to 【 To turn it off 】

　　 Warning level sign

　　1. Measurement results ＜0.15mg/L when , Show green sign （ Security ）

　　2. Measurement results ≥0.15mg/L And ＜0.25mg/L when , Show yellow sign （ Warning ）

　　3. Measurement results ≥0.25mg/L when , Show red sign （ dangerous ）

　　LCD Alcohol tester calibration instructions

　　1. Solution preparation ：

　　a)0.28ml Absolute ethanol +1500ml water , Stir well （ Ethanol should be accurately measured with syringes , Prepare a large number of cups for liquid mixing ）.

　　b) Import 500ml In the fixture bottle , Be careful 50 Change the solution for each product .

　　c) Solution temperature 34±0.5℃, The test instrument bottle can realize constant temperature heating .

　　2. Calibration method ：

　　a) Press and hold for three seconds in the off state ( period 1 Seconds later “ di ” The sound is ignored ), Until I hear “ Diddiddidi ” Release after three rings .

　　b) Immediately press three more times in a row , hear “ di ” A long sound . Security , Warning , The three hazard lights are on at the same time , It enters the calibration state .

　　c) Preheating pour ji when 10 Enter the measurement after seconds , Blowing 6 second , pour ji At the end of the display 0.1mg/L.

　　3. Calibration complete .