What is the purpose of the voltmeter?
A voltmeter, also known as a voltage meter, is an instrument used for measuring the potential difference, or voltage, between two points in an electrical or electronic circuit. Some voltmeters are intended for use in direct current (DC) circuits; others are designed for alternating current (AC) circuits.
A voltmeter is an instrument used for measuring electrical potential difference between two points in an electric circuit. Analog voltmeters move a pointer across a scale in proportion to the voltage of the circuit; digital voltmeters give a numerical display of voltage by use of an analog to digital converter.
- Meters used to measure voltage or current have an internal resistance. Since the meter must be connected to the circuit to make a measurement, the circuit is changed by the resistance of the meter. This is referred to as the meter's "loading effect". Ideally, the voltmeter resistance should be infinite.
- On the other hand, a voltmeter measures the voltage difference between two different points (say, on different sides of a resistor), but it should not change the amount of current going through the element between those two points. So, it should have very high resistance so that it doesn't "draw" current through it.
- Some types of voltmeter have a pointer on a dial, but most have a digital readout. To measure the voltage across a component in a circuit, you must connect the voltmeter in parallel with it. You can measure the voltage across a cell or battery. The more cells, the bigger the voltage.
Measuring potential difference. Potential difference is measured in volts, V. The potential difference across a component in a circuit is measured using a voltmeter. This must be connected in parallel with the component.
- Key Difference: An ammeter is an instrument that is used to measure the currents in a circuit. A voltmeter is an instrument that is used to measure the voltage between two points in a circuit.
- A multimeter or a multitester, also known as a VOM (volt-ohm-milliammeter), is an electronic measuring instrument that combines several measurement functions in one unit. A typical multimeter can measure voltage, current, and resistance. Analog multimeters use a microammeter with a moving pointer to display readings.
- The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second. Electric current is measured using a device called an ammeter.
Working Principle of Voltmeter. The main principle of voltmeter is that it must be connected in parallel in which we want to measure the voltage. Parallel connection is used because a voltmeter is constructed in such a way that it has a very high value of resistance.
- Multimeters are generally not autoranging. You have to set the multimeter to a range that it can measure. For example, 2V measures voltages up to 2 volts, and 20V measures voltages up to 20 volts. So if you've measuring a 12V battery, use the 20V setting.
- Noun. 1. millivoltmeter - sensitive voltmeter that can measure voltage in millivolts. voltmeter - meter that measures the potential difference between two points.
Updated: 3rd October 2019