Solar flux4/14/2023 With the sun overhead, direct radiation that reaches the ground passes straight through the entire atmosphere, all of the air mass, overhead. So not only are there the obvious intensity changes in ground solar radiation level during the day, going to zero at night, but the spectrum of the radiation changes through each day because of the changing absorption and scattering path length. At any location, the length of the path the radiation must take to reach ground level changes as the day progresses. Denver has a mile (1.6 km) less atmosphere above it than does Washington, and the impact of the time of year on solar angle is important, but the most significant changes are due to the earth's rotation (see Figure 4). The ground level spectrum also depends on how far the sun's radiation must pass through the atmosphere. Seasonal variations and trends in ozone layer thickness have an important effect on terrestrial ultraviolet level. Clouds are the most familiar example of change clouds can block most of the direct radiation. 1120 W m -2 global radiation on a horizontal surface at ground level.Ībsorption and scattering levels change as the constituents of the atmosphere change. 1050 W m -2 direct beam radiation, and ca. For a typical cloudless atmosphere in summer and for zero zenith angle, the 1367 W m -2 reaching the outer atmosphere is reduced to ca. Wavelength dependent Rayleigh scattering and scattering from aerosols and other particulates, including water droplets, also change the spectrum of the radiation that reaches the ground (and make the sky blue). Water vapor, carbon dioxide, and to a lesser extent, oxygen, selectively absorb in the near infrared, (as indicated in Figure 3). The "thin ozone layer" absorbs UV up to 280 nm and (with atmospheric scattering) shapes the UV edge of the terrestrial solar spectrum. The widely distributed stratospheric ozone produced by the sun's radiation corresponds to approximately a 3 mm layer of ozone at STP. Ozone strongly absorbs longer wavelength ultraviolet in the Hartley band from 200 - 300 nm and weakly absorbs visible radiation. When molecular oxygen in the atmosphere absorbs short wave ultraviolet radiation, it photodissociates. Atomic and molecular oxygen and nitrogen absorb very short wave radiation, effectively blocking radiation with wavelengths <190 nm. – in case of using lead-free solders, preheating temperatures ofġ00 – 140 ☌ on the topsides are possible.All the radiation that reaches the ground passes through the atmosphere, which modifies the spectrum by absorption and scattering. Preheating: (If preheating system is used) Entering the solder-wave, the temperature on the topside of the pasteboards should be 80 – 110 ☌, dependent on type of boards, lay-out etc. and observe the distribution of the flux. Sprayfluxing: If possible, try at first a quantity of 25 – 50 ml/min. The general rule of applying fluxes applied in principle as low as possible also applies to this product. There are good results for manual, wave and selective soldering, as well as for cable assembly / wire tinning. This flux is very versatile and OPS-compatible. Safety instructions: Please refer to the current MSDS The application can be carried out by any usual application method (except foams).ĮO-S-017 is totally free from corrosion action. The activators are specially designed for the higher temperatures that are required in the manufacture of solar modules, without affecting their effectiveness. EO-S-017 is a NO-CLEAN flux, halide-free formulated and optimized for use in wave, selective and manual soldering processes.ĮO-S-017 leaves no sticky residue. This flux has been specially developed for solar technology, in particular for soldering solar modules, tabber and stringer material, as well as connecting cells.
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