CHAPTER13-17 SIR EFREN

A method of level measurement where the only concern is whether the amount of material is within the desired limits.

A method of tracking the change of level over a range of values.

A continuous level measuring instrument that consists of a glass tube connected above and below the liquid level in a tank and that allows the liquid level to be observed visually.

A gauge glass that uses flat glasses enclosed in metal bodies and covers to protect against breakage when used in boilers or high-pressure vessels, or for other safety requirements.

A flat gauge glass with a special vertical sawtooth surface that acts as a prism to improve readability.

A gauge that consists of a stainless steel float containing a magnet riding in a stainless steel tube where the level indicator consists of horizontally pivoted magnetized vanes painted yellow or white on one side and black on the other in a housing bolted to the level tube.

An intermittent full-range level measuring assembly consisting of a manual or remotely operated switch, a relay and a servomotor, a plumb bob for a weight, and a cable.

A level measuring instrument consisting of a tube extending to the bottom of a vessel; a pressure gauge, single-leg manometer, transmitter, or recorder; a purge flowmeter or sight feed bubble; and a pressure regulator.

A point level measuring instrument consisting of a hollow ball that floats on top of a liquid in a tank and is attached to the instrument.

A continuous level measuring instrument consisting of a floating object connected by a chain, rope, or wire to a counterweight, which is the level pointer.

A liquid level measuring instrument consisting of a buoyant cylindrical object, heavier than the liquid, that is immersed in the liquid and connected to a spring or torsion device that measures the buoyancy of the cylinder.

A point level measuring device consisting of a drive motor and a rotating paddle wheel mounted inside a tank.

The ability of an electrical device to store charge as the result of the separation of charge.

The ability of a circuit to conduct alternating current and is the reciprocal of impedance.

An electrical device that stores electrical energy by means of an electrostatic field.

The insulating material between the conductors of a capacitor.

The ratio of the insulating ability of a material to the insulating ability of a vacuum.

A part of a level measuring instrument and consists of a metal rod inserted into a tank or vessel, with a high-frequency alternating voltage applied to it and a means to measure the current that flows between the rod and a second conductor.

A point level measuring system consisting of a circuit of two or more probes or electrodes, or an electrode and the vessel wall where the material in the vessel completes the circuit as the level rises in the vessel.

A point level measuring instrument consisting of a sealed probe containing a coil, an electrical source that generates an alternating magnetic field, and circuitry to detect changes in inductance.

point level measuring instrument consisting of a light source and a detector that indicates a level of the contents of a vessel when the beam is broken.

A liquid point level measuring instrument where a light source and a light detector, shielded from each other, are mounted in a housing and the light source is directed against the inside of a glass or plastic cone-shaped prism.

He part of a continuous level measuring system consisting of an electronics module, a waveguide, and a float containing a magnet that is free to move up and down a pipe that is inserted into a vessel from the top.

A point level measuring instrument consisting of two probes that extend from the detector into the vessel, with one of the probe tips being heated.

A level measuring instrument that uses ultrasonic sounds to measure level.

The time it takes for a transmitted ultrasonic signal to travel from the ultrasonic level transmitter to the surface of the material to be measured and back to the receiver.

A point level measuring instrument consisting of a vibrating tuning fork that resonates at a particular sound frequency and the circuitry to measure that frequency.

: A level measuring sensor consisting of a radar generator that directs an intermittent pulse with a constant frequency toward the surface of the material in a vessel.

Level measuring sensor consisting of an oscillator that emits a continuous microwave signal that repeatedly varies its frequency between a minimum and maximum value, a receiver that detects the signal, and electronics that measure the frequency difference between the signal and the echo.

: The range of frequencies from the minimum to the maximum value in an FMCW radar level sensor.

The constant time for an FMCW emitter to vary the frequency from the lowest frequency to the highest.

A level measuring detector consisting of a cable or rod as the wave carrier extending from the emitter down to the bottom of the vessel and electronics to measure the transit time.

A level measuring instrument consisting of a laser beam generator, a timer, and a detector mounted at the top of a vessel.

A level measuring system consisting of a radioactive source that directs radiation through a vessel to a detector, such as a Geiger counter, on the other side.

A device that detects and measures nuclear radiation as it strikes a sensitive material, known as a phosphor, producing tiny flashes of visible light.

A device used to weigh large items and typically consists of either piston-cylinder devices that produce hydraulic output pressure or strain gauge assemblies that provide electrical output proportional to the applied load.

The weight of the vessel, piping, and equipment that is supported by the load cell(s).

A granular solid, such as gravel, sand, sugar, grain, cement, or other solid material that can be made to flow.

A valve located on a water column used to determine the boiler water level if the gauge glass is not functional.

The process of discharging water and undesirable accumulated material.

A boiler fitting that reduces the turbulence of boiler water to provide an accurate water level in the gauge glass.

A condition arising in a silo when material has built up over the feeder, blocking all flow out of the silo.

A condition arising in a silo when material in the center has flowed out the feeder at the bottom, leaving large areas of stagnant material on the sides.

The flow of a bulk solid where all material in a silo flows down toward the bottom at the same rate.

He flow of a bulk solid where the material empties out of the bottom of a silo and the main material flow is down the center of the silo, with stagnant areas at the sides and bottom of the silo.

A boiler fitting that shuts the burner OFF in the event of a low water condition.