What is a Voltmeter?
A voltmeter is a measuring instrument used to measure the electric potential difference, also known as voltage, between two points in an electric current. The voltage known as the electric potential energy per unit charge, it is responsible for conducting a current from one electron to another electron.
The amount of positive electrical charge is measured as it enters one point within an electrical circuit, and then negative input is measured as it passes through another point.
In technical terms, voltmeters They are considered as ammeters, this is because they measure electrical current instead of voltage. The voltage It is only measured when the electric current is transmitted in the electric circuit through the resistance.
The voltmeters They were originally galvanometers, they are also known as multimeters because they also measure resistance and current.
What parts does a voltmeter have?
A voltmeter has three parts that you need to know before you can use it:
- Positive input terminal (usually red).
- Negative input terminal (usually black).
- Sample, where you can find the measurement results: If it is analog you will have to read the results from a scale. If digital, the results will be displayed as a reading on an LCD or LED screen.
What functions does a voltmeter have?
Most voltmeters have at least these functions:
- Precise measurements and tests for a variety of electronic devices.
- Measure the voltages.
- Measure direct current.
- Measure continuity.
- Measure resistance.
- Measure the transistors.
- Test the battery.
How does a voltmeter work?
We already saw the parts that make up a voltmeter, so a good example to demonstrate how it is used is when trying to determine the amount of charge remaining in a battery.
Two wires are used: one wire (the red color) is connected from the positive terminal of the voltmeter, to the positive end of the battery. The other wire (the black color) connects from the negative terminal on the voltmeter to the negative point of the battery. Put the voltage meter correct, the voltage of the voltmeter has to be higher than the device, but as close as possible.
How to use a voltmeter?
Types of Voltmeters
There are two types of voltmeters: analog and digital
The digital voltmeters Today they are widely used for the measurement of multiple calculations such as voltage, current and resistance. Similarly, the digital voltmeter has also become a popular choice. There are those who believe that a digital voltmeter is preferable to an analog one. Here are some likely reasons:
Advantages of digital voltmeters
- The main advantage is that it gives you the most accurate measurement compared to its analog counterpart, and the accuracy is not limited to giving correct results, since the analog voltmeters They indicate the value with a needle on a scale, while a digital one has an LED or LCD screen, which can show the output in numbers and even down to decimal points.
- It can be adjusted when necessary to measure ohms, amps and volts.
Advantages of analog voltmeters:
- They are excellent for measuring voltage, current, resistance, frequency, and signal strength.
- It has diode check, an analog voltmeter is more accurate than using a digital voltmeter in this check.
- Short circuit problems can be found with a better output using an analog voltmeter.
- Like the digital version, most of the advanced versions of analog voltmeters have great features like capacitor, diode, and IC (integrated circuit) test modes.
Handling and use of Voltmeters
Voltmeters in general tend to be fragile instruments that can be damaged by thoughtless actions such as using a voltmeter to measure small amounts of current to measure a large voltage.
Yet another reckless move is use a voltmeter Intended for the measurement of large voltages to measure small amounts of voltage. In this scenario, although the voltmeter will not be damaged, the readings obtained will not be accurate. Both extremes must be avoided.
It is important to note that mixing the positive and negative connections, for example connecting the positive terminal to the negative end of the battery can seriously damage the voltmeter, especially if it is analog.
Another precaution to take into account is to first determine if the measurement is a direct current voltage that flows in one direction or is an alternating current that flows back and forth. Different voltmeters are used to handle these different electrical loads.
One last caveat is that while using a voltmeter, care must be taken not to touch any of the terminals with bare fingers, as this will likely shock you, sometimes even to death.
As much as possible, the measurement of a voltage should be a hands-free maneuver with the help of alligator clips.