ohmmeter, instrument for measuring electrical resistance, which is expressed in ohms. In the simplest ohmmeters, the resistance to be measured may be connected to the instrument in parallel or in series. If in parallel (parallel ohmmeter), the instrument will draw more current as resistance increases.

How does an ohmmeter work?

The working principle of Ohmmeter is, when current flow through the circuit or component, the pointer deflects in the meter. When a pointer moves the left side of the meter, it represents a high resistance and responds to low current. The resistive measuring scale is nonlinear in an ohmmeter and the analog multimeter.

How is ohmmeter used to measure the resistance of a component?

Resistance is measured with the circuit’s power turned off. The ohmmeter sends its own current through the unknown resistance and then measures that current to provide a resistance value readout.