The objective of this project is to design a temperature alarm system

The objective of this project is to design a temperature alarm system which measures air temperature and provides an alert when the temperature exceeds its defined upper and lower limit. Specifically, a red LED should turn on when the temperature is lower than the lower limit or higher than the upper limit. When the temperature is between these two limits, a green LED should be on, indicating that the temperature is “normal.”

The options for the lower and upper limits are as shown below. Each teammate should pick a lower and upper limit, and these should be different than those of anyone else in the group.

Lower limit options: 40, 50, 60, 70 ℉

Upper limit options: 80, 90, 100, 110 ℉

The design will consist of multiple stages as shown below in Figure 1. Note that a thermistor is to be used. Also, for the “Amplification Circuit” block, use an operational-amplifier wheatstone bridge (you will need to find this on the internet). For the thermistor, you should use the internet to find a thermistor you want to use and use its datasheet. Teammates should use the same thermistor. A possible alarm circuit is shown in Figure 2. Don’t forget to use commonly available parts.

Figure 1: Block diagram of temperature alarm system

Figure 2

Project Simulation:

Once you have designed the circuit, build it and simulate in Multisim using tolerances, and then pass it to your teammate to test it.

Write a test plan and test your teammate’s design. Be sure to demonstrate that the specifications are met below the lower limit, in the normal range, and above the upper limit.

Project Troubleshooting Manual:

You and your teammate should identify one problem that could cause your design to malfunction and write a short step by step process for a technician in the field, starting with the output symptom, to troubleshoot the circuit and identify how to fix the problem. Assume that the problem is not with the power supply (supplies).

Project Deliverable: Report and the multisim design for your project

Each student will submit an individual report. The report should, as a minimum, include the following:

• Title Page (Name, Partner’s name)
• Description of your project (including the specifications you selected)
• Conceptual Design: Explain the block diagram and what each block does (its functionality) and how it works. Also, be sure to explain when one might use an operational-amplifier wheatstone bridge and its advantages.
• Design methodology (show calculations and provide rationale for design choices; remember that your choices must take into consideration commonly available parts).
• Final schematic in Multisim
• Components/Parts list
• Simulation results for your design
• Testing process and results for characterization and validation of your teammate’s design – screenshots alone will not suffice. Description of process is required along with discussion of results.
• Troubleshooting Manual for one potential problem
• Project Challenges: Note any difficulties you faced during the completion of your design and how you overcame them
• Team Interaction Reflection: Describe how you used Blackboard to facilitate interaction, how you worked with one another in the design phase, challenges you encountered, methods you employed to overcome any challenges.
• Teammate Assessment: Use the Project Participation Rubric below and give your teammate a ranking of Needs Improvement, Competent, or Excellent for the first two items in the rubric: Interacts professionally and Plans and organizes team effort. Be sure to justify your ranking.
• Conclusion
• References
• Data sheet for thermistor