The microwave pulse should easily reach the surface of the product whenever possible. Each object is lodged with the beam produces an echo signal, the more the closer the object (see fig. 4 (A)). If you can not choose a different installation position to avoid strong echoes, they interfere with the measurement and must be suppressed for calibration. This is done similarly to the ultrasonic measurement with the option TDT (Time Dependent Threshold, threshold function time). Since microwaves are polarized, the radiation beam has to be perfectly parallel to the vessel wall, so that the alignment mark on the coupling flange or cable should be placed parallel to the vessel wall (see fig. 4 (B)). Avoid a central position in the tank and keep it separate (at least 300 mm.) Fittings, posts, rings, pipes and walls. E] axis of the transmitter should be perpendicular to the surface. The peak occurs just below the antenna or horn antenna, so that there is no distance restrictions.
Figure 4. emission angle and position within the curvature respectively. The front edge of the rod antenna and the conical horn antennas must be pointed towards the tank (see fig. 5). Avoid as measured through the curtain of disposal of the product or in the whirlpool. Observe the mounting instructions sheet specifications for mounting the still pipe and conduit pipe (dip) in parallel. The pipes must be metal, have a constant diameter and mounted along with the diameter of the horn antenna. For the best product mix, in the still-pipe can be opened slots of a certain size (see fig. 6 (A)). You can use a ball valve full bore to close the measuring point for maintenance (see fig. 6 (B), and in practice, fig. 8). For cases where there are high or even sockets inclined nozzles do not conform to specified requirements for assembly, there are areas of special antenna and extension curves.
Figure 5. Details proper installation. 
Figure 6. Details proper installation. Electrical and electronic
The microwave level indicator must be connected to a power source or AC, either. The high frequency energy radiated is low (about 0.2 mW effective power, which is 500 times smaller than a cell phone, and 2,500 times less than the rate of spread of radiation from a microwave oven). Therefore, industry-level indicators based on microwave signal pulses are safe and, moreover, are not subject to acquisition licensing or other regulation. The output signal is 4-20 mA (active or passive) and some instruments have additional relay output for alarm function. For remote operation, the Micropilot can be deployed with one of the four communication modules include:
• Protocol • Protocol HART PROFIBUS
· Interface RS - 185
· Bus Field Foundation
versions not equipped with digital interface is configured using a portable display module. For Ex (ATEX II 1 / 2 G), this unit is intrinsically safe. This compact unit calibration, which includes a display, a keyboard and an error indicator (see fig. 10), is introduced into the connection compartment of the transmitter. A short cable allows you to manipulate with ease, even when the transmitter is in an awkward position. The display, four lines of text, displays what is being done and what to do next. It also shows the curve of the Seine] envelope when the instrument is detected. There is also a model ATEX EEx ia IIC T6/T4 (safe).
Figure 10. measured calibration Unit Endress + Hauser. Whether
is set to the display module, with the configuration software (ToF-Tool), from a portable terminal or a bus system, the Micropilot always handled from a setup menu with input fields and output of information .
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