Module 1- Intro to Process Instrumentation

Question 1

Instrumentation Definition

Answer 1

a collection of instruments and their application for the purpose of observation measurement and control

Question 2

Basic purpose of instrumentation is

Answer 2

to observe measure and control a pv also to obtain maximum output from the industry with minimum usage of materials

Question 3

process variable definition

Answer 3

the variable/quantity being measured or controlled in the process

Question 4

examples of pv

Answer 4

pressure, level, temperature, flow, electrical conductivity, pH, position, speed, density, mass etc.

Question 5

setpoint definition

Answer 5

the desired value of the process variable

Question 6

measured variable

Answer 6

electronic or pneumatic representation of the value of the pv

Question 7

Process plant is

Answer 7

an arrangement of processing units arranged in a systematic order

Question 8

Process plant objective

Answer 8

is to convert raw materials into a desired product by applying energy in a safe and cost effective manner.

Question 9

(Main criteria for process Instrumentation)
In a successful process plant design instrumentation should address

Answer 9

Safety, Production and Environmental Standards

Question 10

How should instrumentation address the Safety Criteria

Answer 10

the plant should allow for safe containment of process pressures,
construction materials should be able to withstand designed temperatures and chemical concentration
as well as
the control system should be capable of maintaining process parameters at designed points, providing for safe shut and fail safe capability

Question 11

How should Instrumentation address the Production production criteria

Answer 11

quality and quantity of product should be maintained in order to maximize investment returns and
The designed product should meet or exceed original design expectations

Question 12

How should instrumentation address the Environmental Criteria

Answer 12

The plant should comply with environmental regulations regarding air pollution and plant effluent as well as
Have instrumentation to monitor and control plant discharge

Question 13

What are the main components of a control loop

Answer 13

process, measure, control and final control element

Question 14

Define the Process component of the control loop

Answer 14

the physical system we are that we are trying to measure or control. it is a physical or chemical change of matter or energy eg water filtration system, molten melt casting system

Question 15

Define the measurement component of the control loop

Answer 15

this component/block determines the current status of the process parameters, and send the information(measured pv signal) to the control block. this block includes the pse(primary sensing element) sensors and transmitters

Question 16

Define the control component of the control loop

Answer 16

this component receives the information from the measurement instrument (measured pv signal) compares it to the programmed setpoint desired valued and signals the fce to take corrective action if necessary

Question 17

1Define the Final Control Element(FCE) of the control loop

Answer 17

the device which acts to physical change the manipulated variable when signaled to by the controller. ie it controls the flow of materials to the process

Question 18

Define an actuator

Answer 18

An actuator is a part of Final control device that causes physical change in the final control device when signaled to do so.
eg. valve actuator that opens or closes valve in response to controller signal

Question 19

How are actuators usually powered

Answer 19

pneumatically, hydraulically, or electrically

Question 20

Give 8 examples of parts of an actuator system

Answer 20

bellows, diaphragms, springs, gears, hydraulic pivot valves, pistons, electric motors.

Question 21

What are the purposes of Instrumentation (I.C.R.A.M.)

Answer 21

Indicate
Control
Record
Alarm
Measure

Question 22

Define Indicator

Answer 22

a human-readable device that displays information about the process and allows for taking measurements at a measure point at a measurement