Hot:15122013-09-08 14:40:53 From: FTD Automation Instruments
Ultrasonic Level meter Installation
Reasonable installation is critical factor of the ultrasonic level meter’s normal working.
1.1 general hints
ultrasonic level meter Installation must be carried out by trained person in accordance with the manual.
The temperature of the process may not exceed 75℃，and the pressure may not exceed ±0.1 MPa.
The use of metallic fittings or flanges is not recommended.
For exposed or sunny locations a protective hood is recommended.
Make sure the distance between the probe and the maximum level exceeds the blacking distance, because the probe cannot detect any liquid or solid surface closer than the blacking distance to the probe’s face.
Install ultrasonic level meter at right angles to the surface of the measuring material.
Obstructions within the beam angle generate strong false echoes. Wherever possible, the transmitter should be positioned to avoid false echoes.
The beam angle is 8°, in order to avoid large echo loss and false echo, the probe of ultrasonic level meter should not be mounted closer than 1 m to the wall. It is advisable to maintain a distance of at least 0.6m from the center line of the probe for every foot (10cm per meter) range to the obstruction.
1.2 hints for liquid surface conditions
Foaming liquids can reduce the size of the returned echo because foam is a poor ultrasonic reflector. Mount an ultrasonic transmitter over an area of clear liquid, such as near the inlet to a tank or well. In extreme conditions, or where this is not possible, the transmitter may be mounted in a vented stilling tube provided that the inside measurement of the stilling tube is at least 4 in. (100 mm) and is smooth and free from joints or protrusions. It is important that the bottom of the stilling tube stays covered to prevent the ingress of foams.
Avoid mounting the probe of ultrasonic level meter directly over any inlet stream.
Liquid surface turbulence is not normally a problem unless it is excessive. The effects of turbulence are minor, but excessive turbulence can be dealt with by advising the technical parameters or a stilling tube.
1.3 hints for solid surface conditions
For fine-grained solids, the sensor of ultrasonic level meter must be aligned with the product surface.
1.4 hints for in-tank effects
Stirrers or agitators can cause a vortex. Mount the transmitter off-center of any vortex to maximize the return echo.
In non-linear tanks with rounded or conical bottoms, mount the transmitter off-center. If needed, a perforated reflector plate can be installed on the tank bottom directly under the transmitter center line to ensure a satisfactory return echo.
Avoid mounting the ultrasonic transmitter directly above pumps because the transmitter will detect the pump casing as the liquid falls away.
When install to the cold area, should choose the lengthen sensor of the level meter ，make the sensor extend into the container, shun frost and icing .
Edit by FTD Automation Instruments (www.ftdinstruments.com)