A multimeter is a test instrument used to measure different electrical properties in a circuit. It is one of the most useful tools for electronics work.
Measuring Voltage
A multimeter can measure the voltage between two points in a circuit. Voltage is measured in volts(V).
When measuring voltage, the multimeter is connected in parallel with the part of the circuit being tested.
Measuring Current
A multimeter can measure the amount of electrical current flowing through a circuit. Current is measured in amperes(A).
When measurinngcurrent, the multimeter must be connected in series with the circuit so that the current flows through the meter.
Measuring Resistance
A multimeter can measure the resistance of a component or circuit. Resistance is measured in Ohms(Ω).
Resistance should normally be measured with the circuit powered off.
Continuity
The continuity setting checks whether there is a continuous electrical path between two points. The meter will usually produce a continuous beep when a connection is detected.
This is useful for checking wires, switches, breadboard connections and finding breaks in a circuit.
Using the Probes
Most multimeters have two probes:
- Black probe- normally connected to COM
- Red probe- connected to the appropriate socket for the measurement being made.
The exact sockets and settings vary between multimeters, so it’s important to check the meter before taking a measurement.
Basic Safety
Always select the correct measurement mode and range before testing. Never measure resistance or continuity on a powered circuit, and take particular care when measuring current because connecting the meter incorrectly can cause a short circuit.
As I carry out more electronics experiments, I’ll use the multimeter to take measurements and compare them with the expected results.