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Salinity Control

Cascade Switching Hardware and Software

Cascade switching allows the Arduino, with a limit of 20 mA output, to control solenoid valves that need 0.5A or more to actuate.

Control Strategies

The salinity control algorithm uses on/off control with a dead-end determined by measurements of system variability. The measurements are described in the next section. The following slides give a high level overview of why a deadband is used, and how the response time of the system also needs to be taken into account.

  • Lecture slides PDF or PowerPoint on UCL, LCL and dead time.
  • Study document for review of salinity control concepts and system behavior.

Measurements to Characterize Your System

Mass Balance Models for Salinity Control

Sample Hand Calculations

  • Solution to in-class problem on adding mass to correct the salinity in the fish tank
  • Screencast on problem on correcting the salinity of the fish tank (21:15)
control_salinity.txt · Last modified: 2020/02/05 08:00 by gerry