SFC Programming $70$ Marks

Question $1$

Scenario:

In an industrial process control class, students are tasked with creating a Sequential Function Chart $($SFC$)$ program for an

automated tank filling and draining system. The system involves a tank that needs to be filled using Valve $1$ until Level Switch

$1$ is triggered. Once triggered, the tank should be drained through Drain Valve $2$ until Level Switch $2$ is triggered. The cycle

then repeats with the tank being filled again.

SFC Program Requirements:

Design an SFC program to control the tank filling and draining process based on the provided scenario.

Question $1$:

$$ Explain the Sequential Function Chart $($SFC$)$ approach and its significance in industrial process control. $(10$ marks$)$

$$ Based on the scenario, write down the sequence of steps for the SFC program, including transitions and control

actions. $(15$ marks$)$

$$ Describe how the program will ensure the tank is filled by opening Valve $1$ until Level Switch $1$ is triggered. Include

the necessary decision points and transitions. $(15$ marks$)$

$$ Explain the logic your SFC program will use to drain the tank using Drain Valve $2$ until Level Switch $2$ is triggered.

Address any potential challenges in this process. $(15$ marks$)$

$$ Discuss the overall efficiency of the SFC program in managing the tank filling and draining process. Are there any

potential improvements to optimize this process? $(15$ marks$)$

Mark Allocations:

$1.$ SFC Program Understanding and Significance $(10$ marks$)$:

$$ Clear explanation of SFC and its importance in process control $(5$ marks$)$

$$ Discussion of advantages of using SFC in the given scenario $(5$ marks$)$

$2.$ SFC Sequence and Control Logic $(15$ marks$)$:

$$ Correctly sequenced steps and transitions $(8$ marks$)$

$$ Appropriate use of symbols and control actions $(7$ marks$)$

$3.$ Tank Filling Logic and Transitions $(15$ marks$)$:

$$ Accurate representation of Valve $1$ opening and Level Switch $1$ triggering $(8$ marks$)$

Tank Draining Logic and Challenges $(15$ marks$)$:

$$ Accurate representation of Drain Valve $2$ opening and Level Switch $2$ triggering $(8$ marks$)$

$$ Discussion of potential challenges and solutions $(7$ marks$)$

$5.$ Efficiency and Process Optimization $(15$ marks$)$:

$$ Evaluation of the efficiency of the SFC program $(7$ marks$)$

$$ Identification and explanation of potential process optimization strategies $(8$ marks$)$