Vocabulary For Ch. 1 Intro To Instrumentation

Front 1

Harry Nyquist

Back 1

published the first theoretical paper on automatic process control.

Front 2

Manual Control

Back 2

Technician looks at a gauge or sight glass and makes adjustment to a piece of equipment that directly affets a process variable.

Front 3

Flyball Governor

Back 3

first example of feedback control. James Watt 1st to apply to steam engine as speed control mechanism.

Front 4

John Ziegler and Nathaniel Nichols

Back 4

Described new way to tune PID control loops

Front 5

Model 4004 Microprocessor

Back 5

World's first processor on a chip that paved way for development of the modern digital control

Front 6

Process Variable

Back 6

pressure, temperature, level, flow, and analytical. "condition thats controllable"

Front 7

Instrumentation

Back 7

measure and control process variables. Is eyes, ears, and decisionmaking element of equipment

Front 8

Pressure

Back 8

force applied to a unit of area.

Front 9

Gases/Vapors Force:

Back 9

uniformly over all surfaces.

Front 10

Liquids apply Force:

Back 10

accordance to their depth and density

Front 11

Temperature

Back 11

Measure of average kinetic energy of substance. Fahrenheit, Celsius

Front 12

Flow/Flow Rate

Back 12

quitity of fluid that moves through a pepe within a given time. Expressed in volume or mass units per unit of time (GPM) (PPH)

Front 13

Level

Back 13

Position of either height or depth along vertical axis. Surface position of a material in a vessel.

Front 14

Differential (Delta) d/p

Back 14

difference b/t measurements taken from 2 separte points.

Front 15

Alanlytical

Back 15

measure chemical/physical properties of a process stream. Chromatographs, pH meters, and viscosity meters.

Front 16

Other process variables

Back 16

Weight, Speed, Vibration, Acceleration

Front 17

Instrumentation categorized by:

Back 17

Location, Function, Power Source

Front 18

Location

Back 18

Local/Field- instrument located near process
Remote- Inst. located away from process. Receives/transmits signal to another location. E.I. Control room inst.

Front 19

Function

Back 19

Sensing-

Front 20

Control Loop

Back 20

Grp of inst. acting together to control a single process variable.

Front 21

Control Systems have

Back 21

measurement sensor, transmitter, controller, and final control element <Valve

Front 22

First instrument in loop:

Back 22

Sensing/measuring/transmitting

Front 23

Indicating

Back 23

Showing current conditions. Digital readout or graduated scale with pointing device. EI transmitters, recorders and controllers

Front 24

Transmitting

Back 24

Sends signal to a remote location.

Front 25

Transmitters

Back 25

measureing and transmitting device built into a single unit.

Front 26

Recording

Back 26

records/registers a process variable.

Front 27

Controlling

Back 27

maintains a process variable at a specific quintity. May exist as physical entity (local controller) or algorithm (subroutine or program) in a remote location such as a computer or control room rack or cabinet.

Front 28

Power Sources

Back 28

Depends on how all inst. function together inside control loop or how inst functions alone.

Front 29

Pneumatic

Back 29

Loop that uses air/gas as primary power source. They're self purging, and non-electrical. Signal is 3-15PSI (pounds per sq. in)

Front 30

Individual Instruments

Back 30

Combination power sources used within a loop

Front 31

Electronic Instruments

Back 31

powered by electricity.

Front 32

Sub Catagories of Electronic Instumentation are divided by signal and include:

Back 32

Analog, Digital, and analog-digital hybrid

Front 33

Analog

Back 33

continuous electronic signal to measure,amplify, and produce

Front 34

Digital

Back 34

can produce digital or analog output signal. presented in a coded form by packets of 1's and 0's

Front 35

Analog-digital hybrid

Back 35

produce analog output signal. microprocessors in these inst. can be communicated via a frequency signal that shares same wires as analog signal

Front 36

Signal Produced

Back 36

Analog and Digital

Front 37

Analog signal

Back 37

contains all values from one point to another

Front 38

Analog pneumatic signal

Back 38

3-15PSI

Front 39

Analog electronic signal

Back 39

4-20 milliampere (mA)

Front 40

Digital Signals

Back 40

Use binary numbers to represent continuous values or discrete states.

Front 41

Binary number representing analog quantity

Back 41

can be produced by means of an analog to digital (A/D) Converter.

Front 42

Smart transmitters

Back 42

A/D converter built in them. Output signal may or may not be digital

Front 43

What happens to the pressure in a closed container when temperature increases/decreases?

Back 43

Temp increase causes a pressure increase. Directly proportional. EI Radiator

Front 44

What happens to the boiling point of a material when pressure increases/decreases?

Back 44

Boiling point increases when the material pressure increases; boiling point decreases when pressure is lowered.

Front 45

Normal boiling point

Back 45

temperature at which the liquid boils at atmospheric pressure. If vapor pressure exceeds atmospheric pressure, the liquid evaporates

Front 46

What happens to the volume of a material when temperature increases/decreases

Back 46

Volume increases when the temperature increases and volume decreases when temperature decreases. EI coolant system in car

Front 47

What happens to the density of a material when temperature increases/decreases?

Back 47

Density decreases when the temperature increases. density increases when temperature decreases.

Front 48

What happens to the flow of a material when the differential presure across an Orfice plate increases/decreases?

Back 48

Flow rate change causes a change in differential pressure; reduced flow results in decreased differential pressure

Front 49

Flow and Differential Pressure

Back 49

By Daniel Bernoulli. how flow thru a pipe would react to change in pipe diameter.

Front 50

Bernoulli Principle

Back 50

as the speed of a moving fluid increases the pressure within the fluid decreases.

Front 51

How do variable changes affect accurate measurement?

Back 51

A change in one variable in a process can have a profound affect on another measurement variable.