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13. Output devices

▶ Group assignment

  • Measure the power consumption of an output device.

in the beginning, I start To measure the voltage for my PCB by using the multimeter,

I touch the pinout of GND and VCC to measure the voltage and as you see in the picture it is exact (5V)


Power Consumption

In this assignment, we need to measure the power consumption of an output device because I’m using a DC motor (servo) I will measure the power consumption for it.

DC Circuit Power Calculator

  • Voltage is energy per unit charge {Unit=Volts}.
  • Current is the rate of electric charges moving through a conductor{Unit=Amps}.
  • Electrical power is the product of voltage and current{Unit=Watt}.

What is Power Consumption ?

power consumption refers to the electrical energy per unit time,[1] supplied to operate something, such as a home appliance. Power consumption is usually measured in units of watts (W) or kilowatts (kW).

Power (in Watt) is calculated by

Power “P” = Voltage “V” x Current “I” Where V is the voltage across the load and the current passing through the load.

To measure the volatge and current we used Digital Multimeter (DMM)

Voltage, the Digital Multimeter (DMM) is connected in Parallel with the load. Current, the Digital Multimeter (DMM) is connected in Series with the load. Remember to move DMM positive test lead to current measuring position before connecting in series with the load.

The servo have three wires the power,the ground,and the third wire to carry the command pulses After I connect my board with arduino (5V) , I read the voltage and the current.

To measure the current you should break the circuit, first connect the brown wire (GND) on the servo to GND on the Arduino then take the black multimeter probe and connect it with the VCC servo wire and for the Red multimeter probe connect it to the 5V on Arduino to make this operation easy use the alligator cables.

To measure the voltage keeps the circuit close and by using the multimeter probes touch the positive wire (VCC) with Red prob and the negative wire (GND) with black prob and don’t forget to move the mode to right unit measure in multimeter

The power = 5V The current = 0.023A to calculate the power consumption

P = IV P = 0.023x 5 = 0.115W


Last update: August 26, 2022