PLC Programming Quiz

Which of the following PLC programming languages is most commonly used due to its resemblance to electrical relay logic?

• Function Block Diagram (FBD)

• Ladder Logic (LL)

• Structured Text (ST)

• Sequential Function Chart (SFC)

In a PLC program, what does an "AND" operation in Ladder Logic require?

• At least one input to be true

• Both inputs to be true

• Only one input to be false

• Any one input to be true

Which PLC programming language is text-based and similar to Pascal or C?

• Function Block Diagram (FBD)

• Structured Text (ST)

• Sequential Function Chart (SFC)

• Instruction List (IL)

A PLC program in a cargo ship uses a comparator block to check if the ballast water level is within the set range. Which programming language is best suited for this task?

• Instruction List (IL)

• Structured Text (ST)

• Function Block Diagram (FBD)

• Ladder Logic (LL)

What is the primary function of a PLC alarm system?

• To provide automatic emergency shutdown

• To alert operators of abnormal conditions

• To increase the power output of a PLC

• To override manual control of equipment

Which type of PLC alarm is triggered when a process variable exceeds a safe limit, such as high-temperature detection?

• Limit Switch Alarm

• Safety Alarm

• High/Low-Level Alarm

• Diagnostic Alarm

A PLC alarm prevents the ship’s engine from starting unless the shaft is properly aligned. What type of alarm is this?

• High/Low-Level Alarm

• Interlock Alarm

• Safety Alarm

• Diagnostic Alarm

Which of the following is NOT a best practice in PLC programming?

• Using modular design for better readability

• Avoiding documentation to keep the program confidential

• Using consistent naming conventions

• Testing programs in a simulated environment before deployment

A PLC onboard a vessel is responsible for controlling the automatic fire suppression system. What is the primary benefit of integrating PLCs into this system?

• Faster manual intervention

• Improved response time and reliability

• Reduced need for sensors

• Elimination of human oversight

Which programming language is best suited for a complex algorithm requiring loops and conditional statements?

• Ladder Logic (LL)

• Instruction List (IL)

• Function Block Diagram (FBD)

• Structured Text (ST)