Multimeter Tutorial: How to Measure DC Voltage and Current
Image above shows a simple circuit that glows an LED when connected to power supply.. Connecting LED directly to the power supply will damage it, hence aresistance of suitable value must be connected in series for its proper operation. Following the standard color convention,red wire serves as the positive connection lead while black one is the common or negative lead. In this tutorial, we will be measuring DC voltage and current in the circuit.
How to Measure Voltage using Multimeter 
9V DC supply is used to power the circuit. The LED will glow as soon as we connect the wires to the power source. Make sure that all the connections are tight. If the LED doesn’t glow after connecting the supply, then check the connection and the LED.
Step 1:Connect the testing leads to the multimeter.
Step 2: Turn the knob to the DV voltage segment in the multimeter at 40DCV.
Step 3:Connect the probes in the circuit according to the polarity.
How to Measure Voltage using Multimeter
[tie_slideshow]
[tie_slide] Multimeter Tutorial: How to Test LED [/tie_slide]
[tie_slide] Multimeter Tutorial: How to Test a Transistor [/tie_slide]
[tie_slide] Multimeter Tutorial: How to Test and Measure Resistance [/tie_slide]
[/tie_slideshow]
Step 4: Power on the Multimeter.
Step 5: Note down the reading.
The multimeter will show the voltage across the circuit. For example the voltage across this circuit is 6.84V
How to Measure Current using Multimeter:
Multimeter has different procedure for measuring current. Current can be measured in the range ofmilliamperes (400mA max.) to Ampere (10A max.) as shown in the above image.
Multimeter works like an ammeter when ammeter. 
Step1: Turn the knob on the DCA section.
Step2:Choose the current rating. The meter will display current in both rating.
Step3: Connect the testing leads to the current measurement setting.
Step4: Turn ON the multimeter.
Step 5: The multimeter will display the current in the circuit shown as shown in the image below.
How to Measure Current using Multimeter
As shown, 0.4 mA of current flows into the ciruit.
