Answers and Explanations

  1. The student must show their face in the video for credit.
  2. The student must wear safety glasses covering their eyes to get credit.
  3. The student must submit a legible schematic. See the examples below for this lab schematic. Only one schematic is required for submission, but either or both are acceptable. The student can either show the industrial style or the electronic style, and they can show either with or without the latch.
    1.  AMAR-1200-Lab 12-6 - DC Parallel Push Button with LEDs.PNG   
  4. The student must have their name, date, and lab number on the schematic.
  5. The wire colors must be on the schematic.
  6. All components must be labeled. This includes circuit breakers, push buttons, switches, motors, fans, solenoids, resistors, etc.
  7. The circuit must be wired to their schematic.
  8. The circuit has to work.
  9. The student measures the voltage in various places in the circuit.
  10. The student measures the current through the brown wire into the push button. It should be around 44 mA or 0.044 A.
  11. The student measures the current through each LED. It should be around 22 mA or 0.022 A.
  12. The voltage across a parallel circuit is the same, so the voltage into the power push button will be 24V and the voltage across each resistor will be around 22 volts. The voltage across each LED will be around 1.8 to 2 volts.
  13. The current splits as it goes through the circuit. You start out with around 44 mA, and then the current splits to the two branches. One gets 22 mA and the other gets 22 mA. Then, the current comes back together and you get around 44 mA again.
  14. Each LED takes about 22 mA or 0.022 A. There are 2.5 A available from the 24VDC power supply. Therefore, LaTeX: T_{LEDs}=\frac{2.5}{0.022}\:=\:113. Keep in mind that the amount of current used will vary, so anything around 100 LEDs is typically correct.
  15. The student clearly shows lockout/tagout in their video.
  16. The student clearly shows that they have verified with a multimeter that the voltage is at or near 0V.

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