Introduction to measuring instruments (ALIV - Bangladesh)
• What is Ammeter?
An ammeter is a measuring instrument used to
measure the electrical current in a circuit. Electric
currents are measured in amperes (A).
• Type Of Ammeter.
• What is voltmeter?
A voltmeter is an instrument used for
measuring electrical potential difference
between two points in an electric circuit.
Voltage are measured are Volt (V).
• Type of Voltmeter.
• A multimeter or a multitester, also known as a
VOM (Volt-Ohm meter), is an electronic
measuring instrument that combines several
measurement functions in one unit
• A typical multimeter would include basic
features such as the ability to measure
voltage,current and resistance
• A multimeter can be a hand-held device useful
for basic fault finding and field service work
• An oscilloscope previously called an oscillograph
and informally known as a scope.
• Oscilloscopes are commonly used to observe the
exact wave shape of an electrical signal.
Oscilloscopes are usually calibrated so that
voltage and time can be read as well as possible
by the eye.
• Oscilloscopes are used in the
sciences, medicine, engineering, and
• The wattmeter is an instrument for measuring the
electrical power (or the supply rate of electrical
energy) in watts of any given circuit.
• Electromagnetic wattmeters are used for
measurement of utility frequency and audio
frequency power; other types are required for radio
• A typical wattmeter in educational labs has two
voltage coils pressure coils (PC) and a current coil
• Supply voltage is 120v & 240v and current is 1A &
A tachometer is an instrument measuring the
rotation speed of a shaft or disk as in a motor or other
Tachometer is used for measuring rotational speed
Can be used to measure speed of a rotating shaft
Can also be used to measure flow of liquid by
attaching a wheel with inclined vanes
• Signal generators, also known variously as
function generators, RF and microwave signal
generators, pitch generators, arbitrary waveform
generators, digital pattern generators or
frequency generators are electronic devices that
generate repeating or non-repeating electronic
• They are generally used in
designing, testing, troubleshooting, and repairing
electronic or electro acoustic devices; though
they often have artistic uses as well
• An LCR meter is a piece of electronic test
equipment used to measure the inductance
(L), capacitance (C), and resistance (R) of a
• Inductance, capacitance, resistance, and
dissipation factor can also be measured by
various bridge circuits