Jännitemittaria

Jännitemittaria, also known as a voltmeter, is an essential tool in the field of electrical engineering and electronics. It is used to measure the potential difference, or voltage, between two points in an electrical circuit. The device operates on the principle of Ohm's Law, which states that the current flowing through a conductor between two points is directly proportional to the voltage across the two points.

A typical voltmeter consists of a galvanometer, a resistor, and a switch. The galvanometer is a type of ammeter that measures the current flowing through it. The resistor is connected in series with the galvanometer to form a voltage divider, which allows the voltmeter to measure higher voltages. The switch is used to connect the voltmeter to the circuit being measured.

To use a voltmeter, the positive terminal is connected to the point in the circuit with the higher voltage, and the negative terminal is connected to the point with the lower voltage. The voltmeter should be connected in parallel with the component or section of the circuit being measured, as this ensures that the current flowing through the component is not affected by the measurement.

Voltmeters are available in various ranges and accuracies, depending on the specific application. For example, a multimeter, which is a versatile tool that can measure voltage, current, and resistance, may have a voltage range of 200 millivolts to 600 volts. In contrast, a high-precision voltmeter used in laboratory settings may have a range of 0.1 millivolts to 1000 volts.

In summary, jännitemittaria, or voltmeter, is a crucial instrument for measuring voltage in electrical circuits. It operates based on Ohm's Law and consists of a galvanometer, a resistor, and a switch. Proper use involves connecting the voltmeter in parallel with the component being measured, ensuring accurate and safe voltage readings.