Introduction
Background
The Production Supervisor believes that it would save time on the production line if one of his operators did not have to constantly check the fill level of a bin that feeds a production ingredient into the plant.
Someone suggested putting a bin level readout on the wall so the operator could easily read it (so it would take almost no time for the operator to check), but another suggested that you, a control systems technician, could build a circuit that would keep the bin filled between two sensors automatically. The Production Supervisor liked the second idea and the project was assigned to you.
Consider the following setup:

Conveyor 1 feeds Conveyor 2, which feeds the bin. Those are the Conveyors you need to run. The conveyor below the bin is always running (and therefore always taking material out of the bin) whenever the plant is running. The Production Supervisor's goal is to keep the bin loaded with material between the LO and HI sensors.
Assignment
The following must be followed and/or included in your circuit:
- The system will have a "Fill System Start" button. The button is momentary, normally open.
- The system will have a "Fill System Stop" button. The button is momentary, normally closed.
- When the system is on, Conveyor 2 runs and continues to run as long as the system is on.
- When the system is on, Conveyor 1 is automatically turned on and off to maintain the feed level in the bin between the LO and HI point. When material falls below the LO point (as measured by the LO sensor), Conveyor 1 turns on. When material reaches the HI point (as measured by the HI sensor), Conveyor 1 turns off. It stays off until the material again falls below the LO point.
- When the system is off, Conveyor 1 will not run automatically.
- Use two limit switches for your material sensors. Your sensors can be configured however you'd like. In other words, you can choose sensors that close when they sense material (NO) or open when they sense material (NC).
Lab Instructions
- Unplug the Motor Controls trainer.
- Draw a schematic diagram, in Automation Studio or by hand, that represents a circuit that will operate as described above. Make sure your circuit works in simulation before moving on to the next step.
- Build the circuit on the Motor Controls trainer.
- Plug in and turn on the Motor Controls trainer.
- Test the circuit.
- Design, build, and demonstrate a circuit that automatically keeps the bin filled between two sensors.
Submission
To complete this lab, submit a 30-second video following the criteria found in the rubric. If you are working with another student, each of you must record and submit your own video.

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