How to measure a capacitor with a multimeter: Practical guide

Measuring a capacitor with a multimeter is a simple task that allows you to determine if the component is working properly. This article explains the step-by-step process for checking the capacitance of a capacitor and diagnosing possible faults.

What do you need?

• A digital multimeter with capacitance function. See Adajusa Multimeters .

• Test clips (optional, but useful for small capacitors).

• A safe and clean place to work.

Important precautions

1. Discharge the capacitor : Before measuring, make sure the capacitor is completely discharged to avoid damage to the multimeter or personal injury. You can do this by placing a resistor across the capacitor terminals for a few seconds.

2. Check polarity : If you are working with an electrolytic capacitor, identify the positive (+) and negative (–) terminals.

Step by step to measure a capacitor

1. Set up the multimeter

• Turn on your multimeter and select the capacitance measurement function. This is usually indicated by a symbol that looks like a "C" or a capacitor.

2. Prepare the condenser

• Make sure the capacitor is disconnected from the circuit.

• Discharge the capacitor as mentioned above.

3. Connect the multimeter probes

• Connect the multimeter probes to the capacitor terminals.

  • If the capacitor is polarized, connect the positive probe to the positive terminal and the negative probe to the negative terminal.

  • For non-polarized capacitors, the orientation of the probes does not matter.

4. Read the capacitance

• Look at the multimeter's display. It should show capacitance in microfarads (µF), nanofarads (nF), or picofarads (pF), depending on the scale of the capacitor.

Interpret the results

1. Capacitance within specified range : If the measured value matches that indicated on the capacitor, the component is working properly.

2. Capacitance out of range : If the value is significantly different, the capacitor may be damaged or degraded.

3. No reading or infinite reading : This may indicate that the capacitor is open or defective.

4. Shorted Reading : If the multimeter displays "0" or a very low value, the capacitor may be shorted.

Additional Tips

• If your multimeter does not have a capacitance function, you can use a continuity test function to check if the capacitor is shorted.

• For high capacitance capacitors (e.g. greater than 1000 µF), wait a few seconds for the multimeter to stabilize the reading.

• If you need new capacitors, check out Capacitors in Adajusa .

Conclusion

Measuring a capacitor with a multimeter is a simple but crucial process for keeping electronic circuits working properly. By following these steps, you can quickly identify whether a capacitor is working as expected or needs to be replaced. Always work with caution and be sure to discharge capacitors before measuring.