Differences Between an Electrometer and a Voltmeter

Differences Between an Electrometer and a Voltmeter

In this article, we discuss scientific instruments electrometer, voltmeter, the differences between them, and their uses.

The size, shape, purpose, complication, and complexity of scientific instruments varies. Scales, rulers, chronometers, electrometers, voltmeters, thermometers, and other rather rudimentary laboratory equipment are included in this category. Various types of large scientific equipment are also used in the field of science, like particle colliders or radio telescopes. In this article, we will majorly discuss electrometers and voltmeters.

An Electrometer

An electrometer is an electrical scientific instrument that is used to measure a small electric charge or electric potential difference between two points. The credit for the invention of this device was given to William Snow Harris, and it was later improved upon by Lord Kelvin. From historical handcrafted mechanical instruments to high-precision electronic equipment, there are many diverse varieties of electrometers. Voltage and charge measurements can be made with very low leakage currents, as low as 1 femtoampere, by using modern electrometers based on vacuum tubes or solid-state technology.

Digital electrometer

Digital electrometers are modern electrometers that work digitally. That is, the value of the wanted or resultant voltage will be displayed on the screen without any additional effort. Digital electrometers are advanced devices that show high reproductivity and accuracy and can be used for small dimensions also.

A voltmeter

A voltmeter is a device that measures the difference in electric potential between two locations in an electric circuit. It is linked in a parallel manner. It contains a high resistance within it and hence draws very little current from the circuit. Analogue voltmeters use a galvanometer and a series resistor to move a pointer around a scale in proportion to the voltage detected. Amplifier-based voltmeters can detect voltages as low as a few microvolts. An analogue to digital converter is used in digital voltmeters to display voltage numerically on the screen. Working of voltmeters is also based on many wide ranges of categories like, some of the voltmeters are powered by battery and some of them are powered by their own voltage source.

Voltmeter vs Electrometer

An electrometer is designed in such a way that in it parallel resistance is present and has an exceedingly high value, on the order of 1012 ohm, so the load impact is very tiny and may be recorded with high resistance. On the other hand, a voltmeter also has a parallel resistance with the galvanometer such that its resistance is very high and load impact in it is also high.

An electrometer is generally used to measure and detect static electricity, meaning electricity which is generated due to the flow of charged particles from one place to another. On the other hand, a voltmeter is a device which is used to measure an electric potential in units of volts.

Uses of different scientific instruments

An electrometer is used to detect extremely low voltages and currents of the circuits.

A voltmeter is used to detect volts which is a unit of measurement for electric potential.

An ammeter is a device which is used to measure the current from any circuit, which may be direct current or alternate current.

An anemometer is a device which is used to measure the velocity and force of the flowing winds of the atmosphere.

An accumulator is a device which is used to store electrical energy in it.

A barometer is also a scientific device which is used to measure atmospheric pressure.

A colorimeter is a device which measures the intensities of colour.

A pH metre is a scientific instrument that measures the acidity and basicity of the solution.

Conductivity is used to measure the conductivity of the solution, which depends on the number of ions.


From the above discussion, it is clear that scientific instruments are useful for measuring physical quantities like electricity, voltage, pressure, temperature, etc. An electrometer device is used to measure small voltage and electricity, while a voltmeter is used to measure high voltage difference.