Difference Between Analog And Digital Multimeter

A Multimeter also referred to as Multitester, is an electronic measuring instrument that combines several measurement functions in one unit.  A typical voltage can measure voltage, current and resistance. There are two types of Multimeters that is Digital Multimeter and Analog Multimeter.

What Is A Digital Multimeter?

A digital Multimeter is a test tool used to measure two or more electrical values, principally voltage (volts), current (amps) and resistance (ohms). It is a standard diagnostic tool for technicians in the electrical/electronic industries. These multimeters are extremely flexible and enable very many faults to be found in an electronic circuit. 

Digital Multimeters replaced needle-based analog meters due to their ability to measure with greater accuracy, reliability and increased impedance.  With ease of incorporating further functionality into an integrated circuit, many digital Multimeters are able to make a number of other measurements such as capacitance; temperature etc and it can also be used to check different electronic devices such as capacitor, transistor and diodes.

What You Need To Know About Digital Multimeter

• Digital Multimeter is an electronic device that is used to measure multiple electrical quantities such as current, voltage, resistance, capacitance, impedance and diode values. It can also be used to check different electronic devices such as capacitor, transistor and diodes.
• Digital Multimeters provide reading in numeric form for appearance on an LCD.
• The size of digital Multimeter is smaller when compared to that of analog Multimeters.  
• In Digital Multimeters calibration is automatic. These Multimeters have an auto ranging feature.
• Digital Multimeters have ability to accept multiple input signals and user can chose the desired signal on the adjustable display.
• Digital Multimeters are most accurate as compared to analog Multimeters.
• Require analog-to-digital converter (ADC) in order to display the reading on LCD.
• Digital Multimeter shows reading on a digital display (LCD) in the form of numeric values.
• Input resistance of digital Multimeter is constant for all the ranges to be measured.
• Digital Multimeter displays a negative (-) quantity (sign) when the polarity is reversed.
• No zero Ohm adjustment is required in a digital Multimeter.
• To use a Digital Multimeter for measurement, a power source is required.
• Digital Multimeters shows much more susceptibility towards electric noise during measurement.
• Digital Multimeter’s  circuit is more complex when compare d to that of analog Multimeter due to presence of components like encoder, ADC, LCD, logic circuit etc.
• Digital Multimeters measures both basic and advance electrical quantities such as current, resistance, voltage, capacitance, inductance and impedance. It can also be used in diode testing, transistor testing, capacitor testing and more other features.
• Digital Multimeters are more costly when compare to analog Multimeters because of its ability to measure unlimited number of parameters and quantities.
• The output of Digital Multimeters can be interfaced with external equipment.
• Digital Multimeters can measure high frequency ranges when compared to analog Multimeters.

What Is A Analog Multimeter?

Analogue Multimeters have been in use for very many years and sometimes go by the name VOA as a result of the fact that they measure Volts, Ohms and Amps. However, the way analog multimeters operate is fundamentally different than how digital multimeters operate.

Analogue Multimeters are calibrated manually. The range has to be set manually for different measuring quantities by rotating the knob. In order to give an accurate reading analogue multimeters need a high level of sensitivity. They accept only one input signal per operation and have several different options for displaying data; commonly a galvanometer registers movement, though sometimes a simulated pointer or bar graph is used instead. Usually, errors occur as a result of a user’s inability to read the results properly and resistance readings tend to be difficult because the resistance circuit tends to cause scale compression. Also, when testing for resistance, the multimeter can rely on battery power.

What You Need To Know About Analog Multimeter

• Analog Multimeter is an electronic device used to measure limited electrical quantities such as current, voltage and resistance.
• Analog Multimeters provides reading on a scale against pointer.
• Analog Multimeters are larger in size when compared to digital Multimeters.
• Analogue Multimeters are calibrated manually. The range has to be set manually for different measuring quantities by rotating the knob.
• Analog Multimeters accepts only one input signal per operation.
• Analog Multimeters are less accurate due to wrong pointer readings and parallax errors (viewing the pointer of an analog Multimeter from another angle can misinterpret the measurement).
• It does not require analogue-to-digital-converter (ADC) to display reading.
• Analog Multimeter shows the values on a printed value scale against moving pointer.
• Input resistance is not constant in analog Multimeters i.e it keeps changing with range.
• Analogue Multimeter pointer attempts to deflect to the left in case of reverse polarity.
• Zero Ohm adjustment changes with each range in analog Multimeter.
• To use an Analog Multimeter for measurement, a power source is not required. A power source is only required when measuring resistance.
• Analog Multimeters shows less susceptibility towards electric noise.
• Analog Multimeter’s circuit is not complex in nature when compared to that of Digital Multimeters due to absence of components like encoder, ADC, LCD, logic circuit etc.
• Analog Multimeters are used to measure current, voltage and resistance.
• Analog Multimeters are less costly when compared to Digital Multimeters because of the limited number of quantities that it can measure.
• The output of analog Multimeter cannot be interfaced with external equipment.
• The frequency range for analog Multimeters are up to2kHZ.

Also Read: Difference Between Voltage And Current

Difference Between Analog And Digital Multimeter In Tabular Form

 Advantages of Analog Multimeters

• A slight change in signal can be detected more swiftly by analog multimeter than digital multimeter.
• They are cheaper when compared to digital meters.
• They respond very quickly to measurement.
• They do not require batteries unless resistance needs to be measured.

Disadvantages Of Analog Multimeters

• Analog meters are bulky in size.
• They are vulnerable to shock and vibration.
• The pointer movement is slow, can’t be used to measure voltages with frequencies higher than 50 Hz.
• It requires manual reading of parameters from the scale which is can somehow be difficult.
• It does not have a digital circuitry and therefore cannot perform advanced measurements such as frequency, impedance, waveform analysis etc.

Advantages Of Digital Multimeter

• Provides accurate results.
• It is very simple to use because results are displayed in numeric value directly and user need not have to read manually from the scale.
• They are small in size and compact.
• It can be used for measurement of various parameters such as resistance, voltage, current etc.
• They have high input impedance and therefore no loading effect.
• They have a resistance of 20 kΩ/v which is fairly high.
• They can measure various parameters such as resistance, voltage, current etc.

Disadvantages Of Digital Multimeter

• The LCD display depends on battery or external power source. When the battery is low, the display will be dim, making reading difficult.
• It is more expensive when compared to analog type.
• Digital multimeters have a voltage limitation which if increased beyond limit, the meter will get damaged.
• The meter should be used as per the manufacturer’s specification, measurement range and as per category rating. Failure to comply can result to damage to the equipment.

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