Qualitative inspection

Voltimum

Qualitative inspection

Publicerad: 18 mars 2014 · Kategori: Elseminarium

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Electrical equipment Qualitative inspection with Thermal Imagers The electromagnetic spectrum Thermography Introduction What is infrared radiation ? Infrared cannot be seen (but can be sensed by our skin) Visual Image Everything emits infrared radiation A camera converts the infrared image to a visible picture Infrared allows you to see things that you normally cant. Same image in IR Radiation and Temperature Visual image is reflected ,thermal image is emitted! Radiation increases with temperature 30 seconds in a microwave and New image new information Important to know: We are only measuring the SURFACE: Plexiglas covers need be removed, doors need to be open Emissivity: shiny surfaces will be hotter than their apparent temperature Wind can also affect the measurement (Wind chill factor): so you should take into account convective cooling in or outdoors 5 Benefits of using IR technology Measurements are: Non-contact from safe distance Obtained without disturbing production Very sensitive to problem characteristics Detect defects before significant problem Can scan large areas quickly Identifies specific locations 6 Limitations of using IR technology Good Qualitative Measurements mean: Safe distance- if needed use a tele lens to obtain the desired resolution Inspected equipment should have enough load- minimum 40% of nominal load In the case of faulty connections, the load has a very big influence on the faults temperature. Be aware that the temperature of the fault is also...