Help – Level – 0001 – Radar level gauge Endress Hauser-FM52
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There are some questions here; I would appreciate it if the instrument calibration experts and instrument engineers could help answer them. The following questions are related to Endress Hauser’s radar level gauge FM52. What is the difference between [Other media] and [Water-based media (DC>=4)] in the calibration of radar level gauges? Why does the radar level gauge still experience 【full-scale drift】 after 【suppression】? The radar display shows normal behavior during the rise in the tank’s liquid level, while the reading remains unchanged during the drop in level. Why is this? Is the echo often lost? ? How should the blind zone distance be set, and in what situations is it necessary to set a blind zone? What is the difference between a [standard process tank] and a [storage tank]? Why are there these two options for radar level gauges? 【Blank mark】Can the value be greater than the height of the tank? What are the effects of an 【empty mark】 that is too large or too small? What are the differences between flat-bottom tanks, horizontal tanks, and conical-bottom tanks in terms of 【Linearization Type】, and what impact does choosing the wrong one have on radar level gauges? Automatic control instruments
It is my personal opinion, based on subjective judgment as an individual. Meet and exchange knowledge*. 1. The radar echo intensity varies depending on the medium; therefore, it is necessary to distinguish between water and other media (for example, the signal strength for water is 14,000 mV, while that for crude oil is around 4,000 mV, or even as low as 400 mV). 2. Does \"suppression\" refer to filtering? If filtering is involved, and if the intensity of the filtering effect is greater than that of the signal, this can lead to loss of the signal; as a result, signals at full scale or even above full scale may occur (Rosemount instruments may show an over-scale condition, manifested as an output current of 22 mA – this actually occurs because the radar level gauge cannot detect the liquid level and is therefore trying to locate it, which results in an output current that exceeds the normal range). 3. How fast does the liquid level rise or fall? What is the damping time you have set, and what is the approximate response time of the radar level gauge? 4. Echo loss can be caused by insufficient signal strength, obstacles inside the tank, attachments on the signal generator, or other factors related to the conditions inside the tank. 5. Due to their working principle, radar level gauges have certain requirements regarding the measurement range; being too far away, too close, or having an excessive deviation angle can all affect the measurement. Those areas that cannot be measured are referred to as dead zones. Within the nominal measurement range of the instrument, the most common dead zone is a short distance near the transmitter. For blind zones, I generally set a dead zone, which is the distance at the lower end below the installation location of the radar level gauge; this distance is usually set around 200–300 mm. If there is too much noise, and the process conditions permit it, a larger distance will be used. 6. Setting the tank type helps improve the level gauge’s ability to measure the area near the bottom of the tank; if there is no actual option available, unknown can be chosen. 7. As per Rosemount’s usage, it is possible to set default values and parameters, after which the level gauge calculates based on those settings. The result will be based on the parameters you set. 8. Same as question 6
1. It depends on the medium; mainly, it comes down to the value of the dielectric constant. 2. It’s possible that the interference signal at full scale is not being suppressed when you perform suppression, or there is an issue with the way you are suppressing the interference. A decrease in liquid level with no change indicates that there is interference present, and tank calibration is required. 4. The case of echo loss I encountered was when it exceeded the overload range; I’m not too sure about anything else. 5. The blind zone we set at 0.5m6; it’s not entirely clear. 7. The blank mark must not be higher than the height of the tank; otherwise, the display will be exaggerated. 8. Look into these types of containers; it’s best to decide based on the actual circumstances. I’m not very clear about the impact on me.
3. Canning interference suppression is required. Correct