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12. Output devices

This week, as a group assignment, examine the power consumption of the circuit.


The power consumption is obtained by the following formula. W = V × A

If power consumption is multiplied by time, it will become power consumption every hour. Wh = W × h

An example of power consumption in Japan. In Japan, the basic rate changes depending on the number of amps to be contracted.

Amps BasicRate
10A ¥280.80
15A ¥421.20
20A ¥561.60
30A ¥842.40
40A ¥1,123.20
50A ¥1,404.00
60A ¥1,684.80

And the rate of wattage per hour is changed in three steps

kWh Rate
0 - 120 ¥19.52
120 - 300 ¥26.00
300- ¥30.02


Check the power consumption by increasing 2V from 1V

  • 0V
    • 0V
  • 1V → 0.27A
    • 1V
  • 3V → 0.75A
    • 3V
  • 5V → 0.98A
    • 5V
  • 7V → 1.40A
    • 7V
  • Table
    • Table

By measuring the temperature, I was thinking about examining the relationship between power consumption and temperature.
However, when the measurement took time, the temperature rose during that time.
As a result, at 7 V, the Peltier element was destroyed and no current flowed.

Power consumption of Peltier device (TEC-12705)

Power consumption and charge for 1 hour at each voltage

Voltage Ampere Killo Watt per Hour Charge
1V 0.27A 0.00027kWh ¥0.00527
3V 0.75A 0.00225kWh ¥0.0585
5V 0.98A 0.0049‬kWh ¥0.095648
7V 1.40A 0.0098kWh ¥0.191296