How to test an ac capacitor with a multimeter

How to test an ac capacitor with a multimeter. The electronic capacitor uses the capacitor for storing the voltage. Check the capacitor with a multimeter’s help to determine whether it is wrong or good. For this method, the multimeter up and the voltage reads on the lead of the capacitor. The reading voltage should be near the 9V.the voltage will discharge very quickly to 0v when the capacitor starts releasing through the multimeter.

The voltage reading with the help of the capacitor should be done this way by connecting known values of resistance in series with the use of the capacitor. Fix the end of the capacitor with the multimeter knob and then set the knob for measuring the voltage. You should apply the known voltage across the series connection. Then notice the voltage across the capacitor displayed across the capacitor panel.

How to test an ac capacitor with a multimeter

The meter goes very quickly to 0 ohms and then starts increasing gradually. This increase is the sign of a suitable capacitor. In the order when the ohm is not increasing or decreasing, you should replace the capacitor. Any analog or digital multimeter is an option.

Then note the initial voltage reading of the capacitor in the case when it becomes close to the applied voltage. If the task is close, the capacitor is alive; if it is far, the capacitor is dead. A suitable capacitor has low reading at the start, increasing gradually.

When the task is shared all the time, the capacitor becomes shorted. When the capacitor is not retaining this voltage, it means that your capacitor is defective, and you should replace it.

The capacitor burnt when it gave the following signs

  • The burning smell from the exterior air conditioner
  • The noise from the air conditioner
  • An air conditioner takes a while to start the cooling cycle

Testing of an AC Capacitor

All electronics and electronics circuits require a capacitor. There are many ways to test the capacitor: digital multimeter, voltmeter, and ohm meter.

Check to see that there is a connection between the capacitor and the circuit before you begin testing not contact with the terminal during working because if the capacitor has a charge on it, then it will cause electrical shocks to you.

Testing using Digital Multimeter

Testing the capacitor with the help of a multimeter is the most straightforward and effortless way .for testing the capacitor, the digital multimeter is used, which has the feature for capacitance testing.

To prevent electrical shocks, cut the circuit’s connection to the capacitor

  •  The capacitor’s setting should be selected on the digital multimeter.
  •  To the terminal of the capacitor, attach the multimeter’s probes.
  •  If the capacitor is polar, the red probe should be linked to the positive terminal and the black probe to the negative.
  •  Otherwise, for the unpolarized capacitor, you can make any connection between these.
  •  The capacitance of the capacitor can then be read by looking at the multimeter’s display.
  •  When you contrast the measurement with the capacitor’s stated rating, it is clear that the capacitor is in good shape.
  •  If there a significant variation is found, then the capacitor is bad.
  •  If the capacitor is wrong, you can replace the capacitor with a similar rating

Testing of the Capacitor using Analog Multimeter 

  •  If you want to check the capacitor in Avo mode, then follow these steps
  •  First, make sure that the capacitor is discharged fully
  •  Next, grab an AVO meter.
  •  Select the resistance mode from the analog multimeter by rotating the knob.
  •  Make a connection between the capacitor’s terminal and the metal leads.
  •  Then you should notice the reading.

Short Capacitor

The short capacitor shows the low resistance

Open Capacitor

In the case of an available capacitor, it does not show any movement on the ohm meter scale.

Suitable capacitor

This capacitor has a low resistance at the start and then starts increasing immediately to infinity, which means that the capacitors are in good condition.


The capacitor can make a hazardous residual charge, so before touching it or taking any measurement, you should first discharge the capacitor by using a resistor at its terminal. Before you begin testing the capacitor, make sure there is no connection between it and the circuit.

We can get a more precise measurement of the capacitor’s capacitance thanks to the digital multimeter. The tried-and-true approach involves testing the capacitor using a digital multimeter. The benefit of testing is that it tells us whether the capacitor is bad or good. If the capacitor is defective, it is feasible to repair the electronic gadget or replace it.

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