Guided wave radar liquid level gauge, a liquid level measuring instrument in industrial production, is based on the principle of time domain reflection (TDR) to complete the continuous level measurement of liquids, particles and slurries. Widely used in water storage tanks, acid and alkali storage tanks, slurry storage tanks, solid particles, small oil storage tanks, all kinds of conductive, non-conductive media, corrosive media such as coal bunkers, ash bunkers, oil tanks, acid tanks, etc. .
So how to correctly choose the guided wave radar level gauge? Please see the following key points for selection:
1. Confirm the viscosity of the measuring medium
The selection of guided wave radar level gauge must confirm the viscosity of the measurement medium. If the measurement medium is very viscous, it is not suitable to use the guided wave cable pole. This type of contact measurement method, hanging material will affect the signal transmission and reception to generate false signals .
2. Confirm the corrosivity of the measured medium
If the measured medium is corrosive, it is necessary to use a wave guide cable sheathed PTFE or a rod sheathed PTFE product.
3. Definition of range
Generally, if we install the flange face down to the vertical distance from the bottom of the tank, this parameter must be accurate. The lowest probe of the cable is at least 30mm from the bottom of the tank to ensure that the probe does not touch the bottom of the metal tank to generate interference signals. The cable can be set a little longer, so that if you get to the scene, you can cut it yourself, but if you break it, you need to re-customize the cable. Therefore, we must confirm the length of the cable clearly when determining the parameters, so as to avoid the on-site measurement.
*** In addition, it is particularly important to note that for the guided wave cable sheathed PTFE products, the cable length cannot be shortened once confirmed.
4. Confirm whether there is stirring
Select the guided wave radar level gauge to confirm whether there is stirring in the storage tank, where is the position of the fan blade, the blade is very close to the pipe wall, it is not suitable to use the guided wave radar level gauge, or add a bypass tube to measure. The cable or pole should be at least 300mm away from the pipe wall.
5. Confirm the dielectric constant of the measuring medium
If the measured dielectric constant of the liquid medium is very low, you can refer to the use of guided wave double cable or guided wave coaxial radar liquid level gauge, the effect will be better.