Infrared thermometer troubleshooting points to consider
Influence of atmospheric attenuation: The infrared radiation energy on the surface of the electrical equipment under test is transmitted to the infrared detection instrument through the atmosphere, which will be affected by the absorption attenuation of water vapor, carbon dioxide, carbon monoxide and other gas molecules in the atmospheric combination and the scattering attenuation of suspended particles in the air. . The attenuation of equipment radiation energy transmission increases with the distance between the detection instrument and the equipment under test, which will reduce the transmittance of radiation from the equipment under test, so the attenuation increases with the distance. Reducing the radiation contrast between the faulty part and the normal part of the equipment being tested will also reduce the target energy received by the infrared instrument, causing the temperature displayed by the instrument to be lower than the actual temperature value of the fault point being measured, resulting in missed detection or misdiagnosis. Especially for detecting equipment faults with low temperature rise. As the detection distance increases, the influence of atmospheric combination will become greater and greater. In this way, in order to obtain the accuracy of the target temperature, it is necessary to try to choose a season when the ambient atmosphere is relatively dry and clean for detection; to shorten the detection distance as much as possible without affecting the accuracy, and at the same time, a reasonable distance needs to be kept for the temperature measurement results Correction to measure the actual temperature value.
Influence of meteorological conditions: Harsh meteorological environments (rain, snow, fog, strong wind, etc.) will have an adverse impact on equipment temperature detection and often give false fault phenomena. In order to reduce the impact of meteorological conditions, try to conduct detection at night when there is no rain, no fog, no wind and the ambient temperature is relatively stable.
Influence of environment and background radiation: When conducting infrared detection of outdoor power equipment, the infrared radiation received by the detection instrument includes, in addition to the radiation emitted by the corresponding part of the equipment being inspected, reflections from other parts of the equipment and the background, as well as direct incoming radiation. Sun radiation. These radiations will cause interference to the temperature of the part to be measured on the equipment and bring errors to fault detection. In order to reduce the impact of the environment and background radiation, when conducting on-site infrared testing of outdoor electrical equipment, try to conduct it on cloudy days or during sunset and evening when there is no light. This can prevent the influence of direct incident, reflected and scattered solar radiation; for indoor equipment, you can turn off the lighting and avoid the influence of other radiation. For highly reflective equipment surfaces, appropriate measures should be taken to reduce the impact on solar radiation and radiation from surrounding high-temperature objects, or the detection angle should be changed to find the best angle to avoid reflection for detection. In order to reduce the impact of solar radiation and surrounding high-temperature background radiation, appropriate shielding measures should be taken during detection, or appropriate infrared filters should be installed on infrared measuring instruments to filter out the sun and other background radiation. Select an instrument with appropriate parameters and a detection distance for detection so that the part of the equipment being tested is within the instrument's field of view, thereby reducing interference from background radiation.
