It is utilized to measure, amongst other things, the voltage of a battery (volts), the intensity of a current that passes through a lit lightbulb (amps), or the resistance of an electric circuit (ohms).
Normally, they have a central knob that measures volts, amps, or ohms, depending on its position.
The result of the measurement is shown on an LCD (Liquid Crystal Device) screen on digital multimeters.
The probes are applies between the positive and negative terminals of the batteries to measure volts, or between the extremes of a resistance to measure ohms.
To measure amps, you have to open the circuit through which the current intensity is passing and force the current to pass through the multimeter to measure it.
Checking the multimeter
Multimeters have two common flaws: interior 9 V battery is out of charge, or bad probes contact.
Internal 9V battery worn out
Poor contact of the probes
With just one test, we can check that the multimeter’s interior 9 V battery is in a good state, and that the probes are properly connected to the multimeter.
Insert the probes into the multimeter:
RED PROBE
in V
BLACK PROBE
in COM
Turn the knob of the multimeter to any of the positions “.” to measure resistances: a "1" appears on the panel (open circuit)
Touch the red and black probes to each other: a “0” appears on the panel (closed circuit)
The basic functionality is correct. Even with a melted fuse, the majority of multimeters measure voltages and resistances, but not electrical current.
When finished, don’t forget to return the knob to its resting position (OFF) in order to not waste the multimeter’s battery.
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