Voltmõõtja

Voltmõõtja is the Estonian word for voltmeter. A voltmeter is an electrical instrument used to measure the electrical potential difference, also known as voltage, between two points in an electric circuit. It is connected in parallel across the component or section of the circuit where the voltage is to be measured.

Voltmeters typically have a very high internal resistance. This is crucial because connecting a voltmeter in parallel should ideally not draw any significant current from the circuit being measured. If the voltmeter's resistance were low, it would alter the circuit's behavior and thus the voltage being measured.

There are several types of voltmeters. Analog voltmeters use a moving coil mechanism, where a needle deflects across a calibrated scale to indicate the voltage. Digital voltmeters, on the other hand, display the voltage as numerical digits on a screen, often using analog-to-digital converters. Electrodynamic voltmeters are also used, which operate based on the interaction of magnetic fields.

When using a voltmeter, it's important to select the appropriate range for the expected voltage to avoid damaging the instrument. The polarity of the connections also matters for DC (direct current) measurements; connecting it incorrectly can result in a negative reading or damage to the meter. AC (alternating current) voltmeters are designed to measure voltages that change direction periodically.