instrumentation and control system

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[Project Number & Title]
Task 1
P1 Types of sensor and transducers used in process control
Sensors and transducers are the components of an electronic systems which are mainly
used for converting one physical quantity into other. Devices which collectively perform an
input function are called Sensors as they possess sense for physical change. While electrical
transducers are used for converting one kind of energy into another. There are different
types of sensors and transducers used in process system, like Chemical sensors, electrical
current sensors, humidity sensors, optical, torque, magnetic, presence sensors and more.
While mechanical and electrical are two main transducers that are used in process control
system. Mechanical transducers refers to a primary sensing elements’ set which respond
towards changes in a physical quantity, like Bimetallic Strip that reacts to changes made in
temperature and respond when there is a mechanical displacement. While electrical
transducers are those systems which respond towards changes with electrical outputs in
physical quantities.
P2 Functions of sensors and transducers
Transducers refers to a device which is mainly used for converting energy in a system from
one form to another. Mostly, it turns input energy into output energy. In context with
process system, in engineering mechanism this system is used to continuous monitor the
operation variables (like pressure, temperature etc.) of industrial process. In this system,
transducers are employed basically at boundaries of measurement, automation and control
systems, for converting electrical signals to physical quantities like force, torque, motion,
energy, light and more, which is known as transduction. While integration of sensors in
process control system helps in increasing the capacity of device for measuring, analysing
and aggregating the data at localised level. The role of sensors is mainly to detect and
measure the physical effect, which provides information regarding with related property of
system to process system. Thus, both transducers and sensors are used to enhance the
effectiveness of process control system and helps in controlling a plant process upset by
executing the subsequent emergency actions. Role of transducers and sensors in Process
control system also can be analysed in the way how much it is used for minimising
requirement to activate the secondary safety devices.
P3 Signal terminology used in process control system
In process control system, analogue signals are mainly used for transmitting the
sensor readings which are typically found in range of 4 to 20mA. For regulating the valve
position a pressure signal with range 3 to 15 psig is used. When there is 0mA detected then
this terminology shows the loss of sensor which may happen due to loss of power, break,
short and more to the sensor. Another important signal terminologies in process control
system includes
gain, zero and span for linear transmitters, where gain refers to a change
within electrical signal which is divided by change within process variable. While span
defines as the potential range of those process variables which can be measured via the
sensor. Other than this, zero refers to the lowest process variable which is measured by
sensor. Furthermore, other main signals used in process control system are feedback and
actuating signal, where feedback signal is used for generating an error signal by comparing
with reference signal, which is firstly filtered via a controller for producing control input of
system. Along with this, actuating signal also known as error signal shows the control
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