1. Introduction to the instrument LPQ-2 automobile exhaust gas analyzer is to analyze the oxygen content in automobile exhaust gas, so as to judge Whether the emissions of carbon monoxide (CO and hydrocarbons (HC) in the exhaust gas of the car meet the requirements of national standards; it can also be determined from the oxygen content (%) of the exhaust gas to reflect whether the air-fuel ratio of the engine is in power and economy. sexual status. The instrument is specially designed for automobile maintenance and repair departments, which can meet the needs of exhaust gas. It has the characteristics of compact structure, simple operation, convenient use and low price. It is a testing equipment for automobile maintenance and repair industries. 2. Technical parameters 1. Measuring range: 0---25% 2. Measurement accuracy: ±1% 3. Working temperature: 0'C~45'C 4. Relative humidity: ≤85% 5. Response time: ≤15S 6. Working voltage: AC220V 7. The weight is about 7 kg 3. Working principle The instrument uses a plate-type diaphragm oxygen electrode sensor; pure platinum is the cathode, pure silver is the anode, and oxygen is used as the anode. After entering the sensor, the oxygen molecules in the oxygen pass through the diaphragm to the cathode, and produce a chemical reaction under the appropriate polarization voltage, so that the sensor electrode current is proportional to the oxygen content in the gas. After the amplification circuit, the oxygen is directly read by the instrument. percentage content. 4. How to use 1. Debug: (1) Press the power switch and the power indicator light will turn on (2) Turn on the air pump to inhale fresh air, preheat for 15 minutes, and then adjust the ''value'' knob, Make the display show 210, that is, the oxygen content of the atmosphere is 21% (the last-digit is a decimal) in the test room Note: The test range referred to here is based on the altitude where the test is located. Adjustment, for example, if the current instrument is located at an altitude of 1500 meters, the test range needs to be adjusted to 176 and 17. 6% position. - -In general, you can adjust the display to the 210 range. The relationship between the oxygen content in the atmosphere and the change of altitude: 2. Test: 0 beam pollution test for cars Enter the exhaust pipe of the car with a depth of not less than 200mm. At this time, the switch of the instrument and the switch of the air pump should be turned on. After 15 seconds, the display value is stable and the displayed value is read. This value is the oxygen content in the exhaust gas of the car. Under the 0-speed test, when the oxygen content in the exhaust gas is below 14%, the CO and HC emissions meet the national standards. The lower the oxygen content, the better the combustion. When the oxygen content is in the range of 3-6%, the engine is in a dynamic and economical state, that is, empty The fuel ratio is within the theoretical range. Five, matters needing attention 1. Always check the filter element in the probe handle and the filter surface in the filter tube for blockage, such as serious blackening The filter element and filter cotton (absorbent cotton) should be replaced 2. In order to prolong the service life of the instrument, the probe should be avoided to take gas in the exhaust pipe for a long time. 3.