This method uses a direct measurement of the distance (usually height) from the datum line. (a)  

This method of level measurement involves converting readouts and data of a known quantity, such as pressure ratio to the volume. (a)  

A device that rides on the surface of the fluid or solid within the storage vessel. (a)  

It utilizes the theory of Archimedes Principle which states that “the force produced when a body is submerged into liquid with a constant density is equal to the fluid displaced” which means that when a body is partially or fully immersed in any liquid, it is reduced in weight by an amount equal to the weight of the volume of the liquid displaced. (a)  

(a)   is used for the measurement of level or filling height of a liquid.

"Regardless of the shape and volume of a vessel or tank, the hydrostatic pressure at the measuring point of a tank or vessel is proportional only to the filling height." (a)  

The radiation level measurement technique is used to measure the level of fluid or solid in a closed tank using (a)   .

A (a)   is a force transducer for measuring weight. Its output signal is proportional to the weight being measured

(a)   measure the distance to the target by measuring the time between the emission and reception.

Conductivity level switches operate on the principle of (a)   .

Level sensing can be single point, (a)   , direct, or indirect.

(a)   is often used as an indirect method of measuring liquid levels

The advantages of the float sensor are that they are almost independent of the (a)   of the liquid or solid being monitored, are accurate and robust, and have a linear output with level height.

A sight glass or (a)   is a type of level sensor , a transparent tube through which the operator of a tank or boiler can observe the level of liquid contained within .

The level can be calculated using the liquid's (a)   and pressure.

Displacement instruments determine liquid level by sensing the (a)   exerted on a displacer by the liquid it displaces.

(a)   level probes consist of a long rod or cable that protrude into a vessel and its contents.

It measure water level based on the amount of pressure it takes to push an air bubble out of an orifice line (plastic tubing) and into the water body. (a)  

A (a)   stretches the entire height of the vessel, and contact is made between two resistive wires by the head pressure against the submerged length of the tape.

A load cell works by converting (a)   into digital values that the user can read and record.

Measuring instrument in which the echo of a pulse of microwave radiation is used to detect and locate distant objects. synonyms: radar, radio detection and ranging, radiolocation. (a)  

It is measured as the ratio of the current that flows to the existing potential difference. (a)  

(a)   level measuring instruments are used for level detection in silos, tanks and bunkers, for both limit detection and continuous measurement.

(a)   instrumentation yields a signal when radiation interacts with a sensitive material.

This type of meter is capable of measuring the continuous measurement of bulk solids with grain size up to 20 mm, e.g. sands, minerals, plastics, agricultural products, foodstuffs, pharmaceuticals and solid fuels. (a)  

The most common form of restriction that is used in flow measurement. (a)  

(a)   , short pipe with a constricted inner surface, used to measure fluid flows and as a pump.

he designed an instrument with a narrow throat in the middle; fluid passing through the tube speeds up as it enters the throat, and the pressure drops. (a)  

The determination of the quantity of a fluid, either a liquid, vapor, or gas, that passes through a pipe, duct, or open channel. (a)  

To measure the rate of flow by the differential pressure method, some form of (a)   is placed in the pipeline to create a pressure drop.

It is a type of flow meter that measures the velocity of a fluid with ultrasound to calculate volume flow. (a)  

A (a)   is a device that measures the flow rate of a fluid.

It is the last part of venturi tube it is attached to the delivery pipe. (a)  

A (a)   consists of a convergent inlet, whose shape is a quarter ellipse with a cylindrical throat.

The tube consists of a short, straight inlet section followed by an abrupt decrease in the inside diameter of the tube. (a)  

The (a)   is a volume flow meter that measures the volume flow of gas, steam, or liquid, the volume flow of standard conditions, or the mass flow of gas or steam.

An accurate and reliable flow meter for many liquids and gases. It consists of a flow tube with end connections and a magnetic multi bladed free spinning rotor/impeller mounted inside, in line with the flow. (a)  

It detects the flow rate of conductive fluids. (a)  

It is a volumetric flow meter that requires the presence of air bubbles or tiny particles in the liquid stream. (a)  

These devices use the scientific principle of the Doppler effect to measure the volumetric flow through a pipe. (a)  

(a)   ultrasonic flow meters measure the difference in time from when an ultrasonic signal is transmitted from the first transducer until it crosses the pipe and is received by the second transducer.

A (a)   is a positive displacement flowmeter, which is mainly used to measure liquid flow. It is composed of a shell, piston mechanism, and other parts.

(a)   flow meter is a type of Positive Displacement flowmeter which uses the revolution of a piston to directly measure smaller packets of liquid volumes.

It is one of the types of positive displacement flow meter. They operate by having a disc mounted to a central ball. (a)  

The (a)   flow meter comprises oval-shaped, geared rotors that rotate within a housing of specified geometry.

It is based on basic physics of thermal dispersion. (a)  

What are the four (4) main process variables? Differentiate each and give at least two examples of the instruments used to measure these variables and explain the principle of measurement of these instruments. (You can use the back page)