The multimeter is an electrical measuring device, capable of carrying out electrical measurement of three different types: Voltmeter, Ohmmeter and Ammeter.
This tool is able to measure:
• Electric current (direct and alternating) – ammeter function
• Electric voltage (direct and alternating) – voltmeter function
• Electrical resistance – ohmmeter function
• Alternating signal frequency
• Among others
The definition about which measurement will be performed, happens by means of a rotary switch that selects the function to be performed.
There are two types of multimeters, analog and digital.
Analog multimeters – Based on Galvanometers, whose reading is verified by means of electromagnetic force in its pointer.
Digital Multimeters – Composed of a versatile electronic component, called an operational amplifier.
It is based on a high input resistance capable of changing the voltage gain, current or electrical resistances.