How does a displacer type level transmitter work?
Electronic displacer level transmitter technology operates by detecting changes in buoyancy force caused by liquid level change. These forces act upon the spring supported displacer causing vertical motion of the core within a linear variable differential transformer.
What is the principle behind displacer type gauges?
The principle of displacement level measurement is based on Archimedes Principle. Displacement instruments determine liquid level by sensing the buoyant force exerted on a displacer by the liquid it displaces.
What is a torque tube transmitter used for?
Torque tube instrumentation has been a common solution for level control applications. However, many processing plants are converting to a displacer level transmitter, which uses range spring technology, for more reliable level measurement and control.
What is a torque tube drive shaft?
A torque tube system is a power transmission and braking technology that involves a stationary housing around the drive shaft, often used in automobiles with a front engine and rear drive. The purpose of a torque tube is to hold the rear end in place during acceleration and braking.
What is the accuracy range of displacer?
Certain process conditions may interfere with the mechanical buoyancy technology. These conditions include solids, moving parts and dirt or buildup. In addition, switch accuracy is limited to ±0.25 inches (6 mm).
Which of the following is correct for a level to force conversion?
Which of the following is correct for a level to force conversions? Explanation: Liquid used for a level to force conversion should have constant density distribution at all points, it enables consistent measurement of force.
What is the level troll?
A Level troll in and instrument used for measuring the liquid level between two known points. The Level troll works on the buoyancy principal. Leveltrol has a float, which submerses proportionately with liquid level raise in the float chamber.
How do you calibrate a level troll wet calibration in the field?
Wet calibration:
- Fill the displacer housing with water until the level is above the displacer. Adjust the S.G.
- Repeat zero and span steps until both are correct.
- Raise the water level until it reaches the centre line (L) The output pressure should be 9 psi.
- 0%, 25%, 50% , 75% & 100%. Mark on chamber.
How does torque tube work?
The torque tube solves that problem by coupling the differential housing to the transmission housing and therefore propels the car forward by pushing up on the engine/transmission and then through the engine mounts to the car frame, with the reverse happening during braking.
What are the design problems of displacement level transmitters?
An interesting design problem for displacement-type level transmitters is how to transfer the sensed weight of the displacer to the transmitter mechanism while positively sealing process vapor pressure from that same mechanism. The most common solution to this problem is an ingenious mechanism called a torque tube.
How to measure the level of a flexible torque tube?
The weight of the displacer acting on the torque arm, will cause an angular displacement of the free end of the flexible torque tube and this movement will be used to measure the level. This instrument may also be fitted in a separate measuring chamber, fitted to the main vessel.
How does a torque tube rod work?
The torque tube acts as a spring here. The twist on the torque tube will be reduced and the torque tube rod will rotate accordingly as the displacer loses its weight due to an increase in level. This rotation is proportional to the displacer’s weight, which is also proportional to the level increase.
How do I calibrate the displacer level transmitter?
1. Calculate the equivalence water level 2. Set up the Displacer Level Transmitter to column or temporary support as shown in the calibration setup file below. 3. Fill the level transmitter chamber with water up to the centre of the lower part flange of the LIT cage as a zero level.