10. Output devices¶
Group assignment requirements¶
The group assignment for this week is the following:
- Measure the power consumption of an output device.
- Document your work on the group work page and reflect on your individual page what you learned.
DC Power Supply specs¶
A bench power supply is a device that converts Alternating Current (AC) to direct current (DC). Using the power supply gives a stable output power where we can control the output voltage and set a limit of the maximum current the device powered can draw. Which makes it ideal to measure the power consumption since it gives an indication of voltage and current used.
Power supply used: Instek GPD-3303D
Number of output channels: 3
Maximum voltage: 30V
Maximum current: 3A per channel, 5A total
Current measurement accuracy: ±(0.1% + 2 digits)
Output device 1: DC Motor¶
For this group assignment, the first output device measured is a DC motor.
A DC motor converts electrical energy into mechanical energy. It operates based on the principle of electromagnetism, where a current-carrying conductor in a magnetic field experiences a force. The motor outputs rotational motion.
According to the datasheet, this device works with a voltage range of 6-12V. We powered it using the power supply with a set voltage of 12V, and it was drawing a current of 0.04A.
Power in Watts = Current in Amps × Voltage in Volts
Power = 0.04A × 12V = 0.48W
The Power consumption per hour in watt-hour (Wh) is = 0.48Wh
During our tests, we observed that when the motor was stalled at 12 volts, it had a current draw of 1.29A.
Output device 2: White LED¶
The second output device measured is a white LED.
A white LED is a light-emitting diode that emits white light when a current passes through it in the forward direction.
According to the datasheet, this LED operates within a voltage range of 3-3.4V. We powered it using the power supply with a set voltage of 3.2V, and it was drawing a current of 0.02A.
Power in Watts = Current in Amps × Voltage in Volts
Power = 0.02A × 3.2V = 0.064W
The Power consumption per hour in watt-hour (Wh) is = 0.064Wh