How Do You Read a Multimeter?

How Do You Read a Multimeter?

To read a multimeter, set it to the appropriate setting, attach the probes, and test the desired device. Many newer multimeters are digital and can automatically find range, but there are some older analog ones still in use.

  1. Turn on the multimeter, and calibrate the settings

    Multimeters have several settings, such as both AC and DC voltage, resistance/impedance and amperage. More advanced models might include capacitance. Before testing anything, know what you want to measure. Volts are marked as AC or DC. Typically, there are two settings for amperage, and resistance is marked with a symbol that looks like an open letter O with tails. This is the Greek letter known as omega.

  2. Attach the probes

    The black probe goes into the outlet labeled "COM" no matter what you're measuring. The red one goes into whichever socket represents your measurement, such as VAC, VDC or amperage. Touch the probes to the appliance; if resistance is being tested, the appliance needs to be off and disconnected.

  3. Look at the reading

    Most of the time, you get a non-zero result. If, when you're testing resistance, you see OL, it means infinite resistance. This translates to an open circuit, which needs immediate repair. A reading of 0 indicates a short circuit, which is also dangerous.