What is the primary reason that modern control systems log and archive data from plant historian databases?

Correct answer: To provide data for developing algorithms that predict safety and maintenance issues and improve efficiency.

Explanation

Modern plants generate vast amounts of operational data, which is stored in historian databases. This data is a valuable asset used for much more than simple record-keeping. It is analyzed to troubleshoot problems, optimize performance, predict equipment failures, and develop more advanced control models, ultimately leading to safer and more profitable operation.

Other questions

Question 1

What is the primary distinction between a Process Flow Diagram (PFD) and a Piping and Instrument Diagram (P&ID)?

Question 2

According to the ANSI/ISA 5.1-2009 symbols illustrated, what does a simple rectangular box symbol represent in the context of control valves?

Question 3

Based on the ISA-5.1-1984 letter code for instrument symbols, what measured variable is indicated by the first letter 'L'?

Question 4

What does a single circle symbol represent in the context of general instrument and controller symbols?

Question 5

What is the operating principle of a Venturi meter used for measuring volumetric flow?

Question 6

In the context of process control objectives, what is the goal related to 'Production rate'?

Question 7

When drawing preliminary P&I diagrams, which of the following is a basic rule of process control to remember regarding level controllers?

Question 8

In a typical level control arrangement at the base of a column using a pump, where should the control valve be placed?

Question 9

How is pressure commonly controlled in a condenser by manipulating the heat-transfer area?

Question 10

What is the primary purpose of cascade control?

Question 11

In a material balance control scheme for a distillation column, if the bottoms product purity is the primary concern, how is control typically achieved?

Question 12

What are the three basic components of an automatic trip system?

Question 13

What is the international standard, based on the ISA S88 committee's work, that defines the architecture for batch process control systems?

Question 14

What is the primary advantage of using microprocessor-based MIMO (multiple input-multiple output) devices in a process control system compared to conventional SISO (single input-single output) controllers?

Question 15

What function is represented by the letter 'Y' when it appears as a second or subsequent letter in an instrument symbol according to ISA-5.1-1984?

Question 16

How does a Distributed Control System (DCS) differ from a simple instrument panel?

Question 17

What is the primary function of a Programmable Logic Controller (PLC)?

Question 18

When is a bypass control typically used for a heat exchanger?

Question 19

What is the primary objective of a 'temperature-pattern control' or 'dual composition control' scheme in a distillation column?

Question 20

Why is it often impractical to use online composition analyzers for the primary control of distillation columns?

Question 21

What is represented by a control valve symbol with an arrow pointing upwards?

Question 22

Which instrument uses a differential pressure (DP) cell placed between the top and bottom of a vessel to indicate level?

Question 23

According to the guide rules for developing control schemes, where should you include extra connections for instruments that may be needed for future troubleshooting?

Question 24

What is a major limitation of model-based predictive control when it comes to measuring product quality?

Question 25

In a simple flow control scheme for a centrifugal pump with a variable-speed drive, what does the flow controller directly manipulate?

Question 26

When laying out a P&I diagram, when is it necessary to show the relative elevation of process connections to equipment?

Question 27

In the instrument symbol 'TRC', what do the three letters T, R, and C represent respectively?

Question 28

What is the primary drawback of a 'dual composition control' scheme for a distillation column?

Question 29

What type of signal is represented by a solid line with double hash marks crossing it on a P&I diagram?

Question 30

In a simple vaporizer control scheme where the feed is on flow control, how is the level in the vaporizer typically maintained?

Question 31

Which of the following items is NOT expected to be identified with a number on a P&I diagram?

Question 32

What is the operating principle of a pH measurement system using a glass electrode?

Question 33

What does a control scheme where one flow controller's setpoint is determined by the measured flow of another stream represent?

Question 34

Where should the temperature sensor for composition control in a distillation column ideally be located?

Question 35

What is the primary reason that interlocks are included in a plant control system?

Question 36

What type of actuator is represented by the letter 'M' in a circle on a P&I diagram?

Question 37

In a control scheme for a simple liquid phase reactor, pressure is often controlled by what method?

Question 38

For which of the following applications would a spill-back flow control, as shown in Figure 5.11(a), be a typical choice?

Question 40

According to the ISA-5.1-1984 symbol standard, what does the combination 'PT' represent?

Question 41

Which of the following is a key safety objective of instrumentation and control schemes?

Question 42

When is temperature control generally considered ineffective for a condenser?

Question 43

According to the guide rules, what is the most responsive way to control pressure?

Question 44

What type of instrument is represented by a circle with a square around it on a P&I diagram?

Question 45

What is the key characteristic of a 'material balance control scheme' for a distillation column?

Question 46

What is the symbol for a self-contained backpressure regulator?

Question 47

Why might a designer specify a separate, dedicated trip system for a hazardous situation rather than relying on the main process control system's alarms?

Question 48

In a batch distillation control scheme as shown in Figure 5.18, how is the product composition often inferred for control purposes?

Question 49

What type of control element is typically used to manipulate the overall plant material balance?

Question 50

What is the primary distinguishing feature of a shared display device with software alarms, as shown in the symbol in Figure 5.6?