How resistance is measured by using ohm meter method

Interview Questions Electronics
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  1. Series ohm meter method
  2. Shunt ohm meter method.
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An ohmmeter is an instrument that is used to measure the resistance of a component or an electrical circuit.

Ohmmeter

Here are the general steps for using an ohmmeter to measure resistance:

  1. Turn Off the Power: It’s very important to ensure that the power is disconnected from the circuit or component you are testing. This is because most ohmmeters use their own internal power source to generate a current, and external power sources can interfere with the measurement or damage the meter.
  2. Disconnect the Component: If you are measuring the resistance of a specific component within a circuit (such as a resistor), it is usually a good idea to disconnect one end of the component from the rest of the circuit. This ensures that you are only measuring the resistance of the component itself, rather than the combined resistance of multiple circuit elements.
  3. Set the Ohmmeter: Turn on the ohmmeter and set it to the appropriate resistance range. If you’re not sure what range to use, start with the highest range and work your way down.
  4. Connect the Probes: Connect the ohmmeter’s probes to the component or circuit you are testing. It doesn’t matter which probe (red or black) you connect to which end because resistance is not a directional property.
  5. Read the Measurement: The meter will then display the resistance. If the display reads “1” or “OL” (for overload), this typically means that the resistance is too high for the range you have selected on the meter. You will need to select a higher range. If the meter reads “0”, the resistance might be too low for your chosen range, and you should select a lower range.
  6. Interpret the Results: Based on the value you get, you can determine if the component is functioning properly. For example, a wire should have low resistance, while a resistor should have a resistance close to its rated value.

Remember to always take necessary safety precautions while handling electrical equipment. Do not attempt to measure resistance in live circuits as it could lead to dangerous situations and damage the ohmmeter.