Output Device - Group Assignment


Objective of This Week

The goal of this week's activity is to measure the power consumption of an output device using a DC Variable Power Supply. This exercise helps in understanding how voltage, current, and load influence the power consumed by motors and other electronic components.


DC Variable Power Supply Overview

A variable DC power supply is a lab instrument used to safely power and test electronic circuits. It allows controlled voltage and current output, making it ideal for learning, prototyping, and performance testing.

Key Features

  • Adjustable Output: Voltage and current can be set (e.g., 0–30 V, 0–10 A).
  • Versatile: Suitable for motors, LEDs, microcontrollers, sensors, etc.
  • Real-Time Monitoring: Shows live voltage and current readings.
  • Built-in Protections: Short-circuit, overload, and over-temperature protection.
  • Accurate Testing: Helps analyze device behavior under different loads.
  • Safe for Learning: Standard tool in electronics labs.
  • Reliable: Long operational life when used with proper ventilation.

Specifications

Parameter Specification
Type Variable DC Power Supply
Maximum Output Voltage 30 V DC
Stable Output Voltage 24 V DC
Maximum Output Current 10 A
Stable Output Current 5 A
Output Power 120 W
Voltage Adjustability Yes (Variable)
Application Testing, Prototyping, Lab Use

How to Use the DC Power Supply

  1. Connect the DC power supply to AC mains and switch it ON.
  2. Adjust the voltage and current limit using the control knobs.
  3. Connect the output terminals to your load (Red = +, Black = –).
  4. Power the device and observe the readings on the display.
  5. Adjust settings while monitoring current to avoid overload.

Safety Precautions

  • Always start with low voltage and increase gradually.
  • Never exceed the rated values of your device.
  • Ensure proper heat dissipation and ventilation.
  • Double-check polarity before connecting the load.
  • Turn OFF the power supply before making any wiring changes.

Testing the Output Device (DC Motor)

Setup

  • DC motor connected to power supply
  • Potentiometer used to vary the load
  • Power supply set to 5V

Procedure

  1. Set the DC power supply to 5V.
  2. Start the motor and adjust the potentiometer to vary the load.
  3. Observe the current fluctuation on the power supply display.
  4. Maximum current observed: 0.09 A

Power Calculation

Given:

  • Voltage, V = 5V
  • Current, I = 0.09 A

Using the formula:

P = V × I
P = 5 × 0.09 = 0.45 W

So, the DC motor consumes approximately 5.5 watts at full load under this test condition.


Conclusion

Through this experiment, we successfully measured the power consumption of a DC motor using a variable DC power supply. By monitoring voltage and current, we can calculate power and understand how load variations affect performance.

Learning Outcomes

  • Understood how to operate a DC variable power supply safely.
  • Learned to measure current and voltage for an output device.
  • Calculated power consumption (in watts) using the formula P = V × I.
  • Gained practical insight into how load affects motor current draw.