takistusmõõtja

A takistusmõõtja, also known as an ohmmeter, is an electrical instrument used to measure the electrical resistance of a circuit or component. It quantifies how much a material opposes the flow of electric current. The unit of resistance is the ohm, symbolized by the Greek letter omega (Ω).

Takistusmõõtjad operate by applying a known voltage across the component to be measured and then measuring the resulting current. According to Ohm's Law (V = IR), resistance (R) can be calculated by dividing the voltage (V) by the current (I). Modern digital takistusmõõtjad often display the resistance value directly as a numerical readout.

These instruments are fundamental tools in electronics and electrical engineering for diagnosing faults, verifying component values, and ensuring proper circuit operation. They are used to check for open circuits (infinite resistance), short circuits (near zero resistance), and to confirm the specified resistance of resistors and other components.

Takistusmõõtjad come in various forms, from handheld multimeters that combine resistance measurement with voltage and current capabilities, to specialized benchtop instruments for high-precision measurements. The range of resistance that a takistusmõõtja can measure varies widely, from fractions of an ohm to millions of ohms (megaohms). When using a takistusmõõtja, it is crucial to ensure the circuit being measured is de-energized to avoid damage to the instrument or inaccurate readings.