A basic look at the electronic measuring systems and devices used to measure electrical quantities

1. ELECTRONIC MEASURING
SYSTEM
BY – SAMIR K

2. ELECTRONIC
MEASURMENT
• An electronic instrument is the one which is
based on electronic or electrical principles for
its measurement function. The measurement
of any electronic or electrical quantity or
variable is termed as an electronic
measurement.
• . The major problem with any measuring
instrument is the error. Hence, it is necessary
to select the appropriate measuring
instrument and measurement procedure
which minimises the error.

3. MEASURMENT ERRORS
• The errors, which occur during
measurement are known
as measurement errors.
• Gross Errors
• Random Errors
• Systematic Errors

4. • GROSS ERRORS
• The errors, which occur due to the lack of
experience of the observer while taking the
measurement values are known as gross errors.
• SYSTEMATIC ERRORS
• If the instrument produces an error, which is of a
constant uniform deviation during its operation is
known as systematic error.
• RANDOM ERRORS
• The errors, which occur due to unknown sources
during measurement time are known as random
errors.

5. ADVANTAGES OF EMS
THE ADVANTAGES OF AN
ELECTRONIC MEASUREMENT
ARE
1. MOST OF THE QUANTITIES
CAN BE CONVERTED BY
TRANSDUCERS INTO THE
ELECTRICAL OR ELECTRONIC
SIGNALS.
2. AN ELECTRICAL OR
ELECTRONIC SIGNAL CAN BE
AMPLIFIED, FILTERED,
MULTIPLEXED, SAMPLED AND
MEASURED.
3. THE MEASUREMENT CAN
EASILY BE OBTAINED IN OR
CONVERTED INTO DIGITAL
FORM FOR AUTOMATIC
ANALYSIS AND RECORDING.
4 THE MEASURED SIGNALS CAN
BE TRANSMITTED OVER LONG
DISTANCES WITH THE HELP OF
CABLES OR RADIO LINKS,
WITHOUT ANY LOSS OF
INFORMATION

6. TRANSDUCERS AND TYPES
• A device that converts variations in a physical quantity, such as pressure or brightness,
into an electrical signal, or vice versa.
• TYPES:-
• Temperature transducers (e.g. a thermocouple)
• Pressure transducers (e.g. a diaphragm)
• Displacement transducers (e.g. LVDT)
• Oscillator transducer.
• Flow transducers.
• Inductive Transducer.

7. ELECTRONIC TESTING EQUIPMENT
• VOLTMETER MULTIMETER OSCILLOMETER
AMMETER LCR METER OHMMETER

8. VOLTMETER
• As the name suggests, voltmeter is a measuring
instrument which measures the voltage across
any two points of an electric circuit. There are
two types of voltmeters:
• DC voltmeter:-
• DC voltmeter measures the DC
voltage across any two points of an electric
circuit.
• AC Voltmeter:-
• AC voltmeter measures the AC
voltage across any two points of an electric
circuit.

9. MULTIMETER
• Multimeter is an electronic instrument used to
measure the quantities such as voltage,
current & resistance one at a time.
• It can be used to measure DC & AC voltages,
DC & AC currents and resistances of several
ranges

10. AMMETER
• Ammeter is a measuring instrument which measures the current flowing through any two points of an electric
circuit.
• There are two types of ammeters: DC ammeter, and AC ammeter.
• AC AMMETER
• AC ammeter measures the AC current that flows through any two points of an electric circuit.
• DC AMMETER
• DC ammeter measures the DC current that flows through any two points of an electric circuit.

11. OHMMETER
• Ohmmeter is used to measure the value
of resistance between any two points of
an electric circuit.
• It can also be used for finding the value
of an unknown resistor.
• There are two types of ohmmeters:
series ohmmeter, and shunt ohmmeter.

12. LCR METER
• An LCR meter is a type of electronic test equipment used to measure
the inductance (L), capacitance (C), and resistance (R) of an electronic
component.
• The LCR meter measures current, voltage and phase angle and
calculates the corresponding LCR values

13. RECORDING
INSTRUMENTS
• Definition: The recording instrument is defined as
the instrument which records the continuous
variation of the magnitude of an electrical
quantity for a particular period. It is used in a
placed where the continuous reading of circuit
conditions is required. The record is used for future
reference or computational work.
• The voltmeter, thermoscope, ECG
machine, galvanometer recorder are the examples
of the recording instrument

14. PERFORMANCE
CHARACTERISTICS
• The characteristics of measurement
instruments which are helpful to know the
performance of instrument and help in
measuring any quantity or parameter, are
known as Performance Characteristics.
• Performance characteristics of instruments can
be classified into the following two types.
• Static Characteristics
• Dynamic Characteristics

15. STATIC
CHARACTERISTICS
• The characteristics of quantities or
parameters measuring instruments
that do not vary with respect to time
are called static characteristics.
• 1.Accuracy
• 2.Precision
• 3.Sensitivity
• 4.Resolution
• 5.Static Error

16. • PRECISION
• If an instrument indicates the same value
repeatedly when it is used to measure the
same quantity under same circumstances
for any number of times, then we can say
that the instrument has high precision.
• SENSITIVITY
• The term sensitivity signifies the smallest
change in the measurable input that is
required for an instrument to respond.

17. • Resolution
• If the output of an instrument will change
only when there is a specific increment of
the input, then that increment of the input
is called Resolution.
• STATIC ERROR
• Static error signifies the inaccuracy of the
instrument
• If the static error is represented in terms of
percentage, then it is called percentage of
static error.

18. DYNAMIC
CHARACTERISTICS
The characteristics of the instruments, which are used to
measure the quantities or parameters that vary very quickly
with respect to time are called dynamic characteristics.
Speed of Response
Dynamic Error
Fidelity
Lag

19. • SPEED OF RESPONSE
• The speed at which the instrument responds
whenever there is any change in the quantity
to be measured is called speed of response. It
indicates how fast the instrument is.
• LAG
• The amount of delay present in the response
of an instrument whenever there is a change
in the quantity to be measured is called
measuring lag. It is also simply called lag

20. • Fidelity
• The degree to which an instrument
indicates changes in the measured
quantity without any dynamic error
is known as Fidelity