New project: several Rosemount 3300 guided-wave radar level gauges are showing readings
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This post was last edited by liu530014416 on 2020-7-30 20:59. It’s a new project; the tank is empty. However, several Rosemount 3300 level gauges show a liquid level of 30–40 cm. When checked using Hart, the LRV value was 0.14 M, while the URV was at the designed value; all other parameters also seemed correct. Why is there a liquid level display on the header? Could it be that the tank is empty? There’s also a model 5300: when it’s powered on, it shows a liquid level of 0; after a while, it displays the highest level reached. The parameters seem to be correct as well. There’s another question: does the length of the wave guide include the length of the weight? The length should be calculated including the weight as well. ******************************************************************* ******************************************************************* The 3300 level gauge defaults to a dielectric constant of 1 for Vapor and 1.96 for Product. There is a 3300 level gauge used for measuring acid flow; today the dielectric constant value for Product was changed to 80 (the dielectric constant of sulfuric acid is 84), and as a result the level reading showed 0. (It’s not clear whether the readings will be accurate if sulfuric acid is poured into the tank in the future.) How does changing the dielectric constant of an empty container affect the measurement values? But there is a device for measuring water level, with a dielectric constant set at 1.96 (the dielectric constant of water is 78), and it provides very accurate readings; the values I obtained using a meter were the same as those shown by the device.
Generally, the dielectric constant is adapted automatically by the radar, so no separate setting is required; however, in special cases it may need to be adjusted, as this parameter is inherent to the medium. If it is too low, the radar cannot function properly, and artificially increasing it doesn’t serve any purpose.
Speaking of the weight, its height is included in the model specification; however, when entering the cable length during configuration, there is no need to specify the height of the weight. Remember!
The radar needs to be configured. By displaying a liquid level of 30 centimeters, you mean when the tank is empty, right? It’s possible that the tank height value set in the radar configuration is 30 centimeters higher than the length of the cable. For example, if the tank is 2 meters high and the cable is 1.7 meters long, in this case an empty tank will show a liquid level of 30 centimeters. Therefore, the radar needs to be configured based on actual parameters, including but not limited to tank height, measurement range, blind zone, antenna type and length, and tank geometry. If there are 475, it’s not difficult to achieve