2. MEASUREMENT
MEASUREMENT IS THE ACT OR RESULT OF
COMPARISON BETWEEN A GIVEN QUANTITY
AND A STANDARD QUANTITY CHOSEN AS A
UNIT OR IN SIMPLE WORDS MEASUREMENT IS
THE PROCESS OF COMPARING KNOWN
QUANTITY WITH THE UNKNOWN QUANTITY.

3. EXAMPLE OF MEASUREMENT
You can measure how long things are, or how
tall, or how far apart they are. Those are are all
examples of length measurements.
Example: This fork is 20 centimeters long
HERE WE ARE COMPARING A UNKNOWN QUANTITY(FORK LENGTH) WITH A KNOWN
QUQNTITY(SCALE)

4. TYPES OF MEASUREMENT
Typically measurements fall into two categories
DIRECT MEASUREMENT
INDIRECT MEASUREMENT

5. DIRECT MEASUREMNT
IN DIRECT METHOD OF MEASUREMENT THE QUANTITY UNDER
MEASUREMENT IS DIRECTLY MEASURED BY USING A INSTRUMENT
FOR EXAMPPLE MEASUREMENT OF CURRENT BY
AMMETER,MEASUREMENT OF VOLTAGE BY VOLTMETER OR
MEASURING LENGTH OF FORK BY USING SCALE.

6. INDIRECT MEASUREMNT
IN INDIRECT METHOD OF MEASUREMENT THE QUANTITY UNDER
MEASUREMENT IS MEASURED INDIRECTLY BY USING KNOWN
QUANTITY RELATED TO IT.
FOR EXAMPPLE RESISTANCE CAN BE MESURED BY USING VOLTAGE AND AMMETER
FOR EX:-RESISTANCE=VOLTAGE/CURRENT

7. INSTRUMENT
AN INSTRUMENT IS A DEVICE THAT PERFORM THE ACTION OF MEASUREMENT BY
USING SOME CIRCUITRY.
FOR EX AMMETER, VOLTMETER, OHMMETER
AMMETER VOLTMETER

8. CLASSIFICATION OF INSTRUMENTATION
SYSTEM
ANALOG SYSTEM
DIGITAL SYSTEM

9. CLASSIFICATION OF INSTRUMENTATION SYSTEM
ANALOG SYSTEM-ANALOG FUNCTION MAY BE DEFINED AS
CONTIONIOUS FUNCTION.IT IS A SYSTEM WHICH IS USED FOR
MEASUREMENT OF INFORMATION IN ANALOG FORM IS CALLED
ANALOG SYSTEM.
DIGITAL SYSTEM-DIGITAL FUNCTION MAY BE DEFINED AS DISCRETE
OR CONTIONIOUS PULSES.IT IS A SYSTEM WHICH IS USED FOR
MEASUREMENT OF INFORMATION IN DIGITAL FORM IS CALLED
DIGITAL SYSTEM.

10. BLOCK DIAGRAM OF MEASUREMENT SYSTEM
DISPLAY
TRANDUCER SIGNAL AMPLIFIER OR READ
CONDITIONER OUT
POWER
SUPPLY

11. TRANSDUCER
A TRANSDUCER IS A DEVICE THAT CONVERTS ONE FORM
OF ENERGY TO ANOTHER. ENERGY TYPES INCLUDES (BUT
ARE NOT LIMITED TO)ELECTRICAL,MECHANICAL OR ANY
DEVICE WHICH CONVERTS ENERGY CAN BE CONSIDERED
A TRANSDUCER.TRANSDUCER ARE WIDELY USED IN
MEASURING INSTRUMENT.

12. SOME COMMON EXAMPLE OF TRANSDUCER
A MICROPHONE CONVERTS SOUNDS TO
VOLTAGE.
 LDR CONVERS BRIGHTNESS OF LIGHT
INTO RESISTANCE.
 VARIABLE RESISTANCE CONVERT
POSITION TO RESISTANCE.
THERMISTOCONVERT TEMPRATURE TO
RESISTANCE.

13. TYPES OF TRANSDUCER
ACTIVE TRANSDUCER
PASSIVE TRANSDUCER

14. ACTIVE TRANSDUCER
Definition– an active transducer is defined as a
transducer which generates its own electrical voltage
during conversion. It does not require any external
battery supply for its working.
Examples –
Solar cell – when it is exposed to strong sunlight or
any other light, it converts light energy into
proportional DC voltage.

15. PASSIVE TRANSDUCER
Definition – passive transducer is defined as the
transducer which requiresexternal battery voltage to
operate. Also it only changes its parameter like
change in resistance or capacitance during
conversion.
Examples –
LDR (Light Dependent Resistor) – when LDR is
exposed to light, its resistance decreases (less than
10W) proportionally & when it is dark its resistance is
very high (several MW).

16. SIGNAL CONDITIONING
SIGNAL CONDITIONING IS USED TO PREAPARE THE TRANSDUCER’S
OUTPUT TO A MEASURABLE FORM.THE OUTPUT OF TRANSDUCER MAY
BE TOO SMALL OR DISORTED ONE.WHICH MAY BE DIFFICULT TO BE
OBSERVED.TO REMOVE THIS DIFFICULTY SIGNAL CONDITIONING IS USED
TYPES OF SIGNAL CONDITIONER
AC SIGNAL CONTIONING
 DC SIGNAL CONDITIONING

17. POWER SUPPLY
A power supply is a device that supplies electric
power to an electrical load. The term is most commonly
applied to electric power converters that convert one
form of electrical energy to another, though it may also
refer to devices that convert another form of energy
(mechanical, chemical, solar) to electrical energy.
A regulated power supply is one that controls the output
voltage or current to a specific value; the controlled
value is held nearly constant despite variations in either
load current or the voltage supplied by the power
supply's energy source.

18. DISPLAY OR READ OUT
A display device is an output device for presentation
of information in visualor tactile form.When the input information is supplied
as an electrical signal, the display is called an electronic display.
Digital clocks display changing numbers.
The digital display of a calculating machine.
Segment displays
The segments are usually single LEDs or liquid crystals. They are mostly used
in digital watches and pocket calculators There are several types:
 Seven-segment display(most common, digits only)
 Fourteen-segment displaySixteen-segment display
 Sixteen-segment display
 HD44780 LCD controllerwidely accepted protocol for LCDs.