- Refer to Figure 77. For control loops 1 and 2. What is the control strategy?
A. Cascade.
B. Ratio.
C. Feed forward.
D. Feedback
- Refer to Figure 44. What is the correct loop configuration?
A. The valve is fail open and the controller
B. The valve is fail
C. __________
D. __________
- Refer to Figure 47. Given the following information:
- Firing rate demand = 20%
- Fuel air ratio = 2:1
- Fuel flow = 20%
- Minimum air flow setting = 5%
What is the set point for the air flow controller?
A. 5%
B. 10%
C. 25%
D. 40%
- An integrating process is originally at a steady state. When the controller output is
increased by 10%, what is the expected response of the process variable?
A. Delayed response, then it ramps up at a steady rate until its upper limit is achieved.
B. Rapid increase, then it gradually slows until it reaches a steady state.
C. Delayed response, a rapid increase, then it gradually slows until it reaches a steady state.
D. Rapid increase, then it ramps up at steady rate until it reaches a steady state.
- Refer to Figure 76. Given the following information:
- Process variable = oscillating ± 5%
- Period of oscillation = 180 seconds
- Controller gain setting = 1.8
In a PID controller, which tuning settings should be used?
A. Gain of 0.3, Reset of 0.4 min/rpt; Rate of 1.5 min.
B. Gain of 0.8, Reset of 2.5 min/rpt; Rate of 1.5 min.
C. Gain of 1.1, Reset of 1.5 min/rpt; Rate of 0.4 min.
D. Gain of 1.1, Reset of 2.5 min/rpt; Rate of 0.4 min.
- A reverse acting PI controller with a gain of 2 and a reset of 2 minutes per repeat has a 40% output in steady state. The process variable (PV) decreases by 10% for 1 minute, and then increases by 10%. After another 2 minutes, what is the output?
A. 30%
B. 40%
C. 50%
D. 70%
- Refer to Figure 29. What is the configuration of the control loop if steam must be shut down in case of a problem?
A. Valve is fail open, PIC is direct-acting, TIC is reverse acting, and controller algorithm is feed-forwarding.
B. Valve is fail open, PIC is reverse-acting, TIC is direct acting, and controller algorithm is cascade.
C. Valve is fail closed, PIC is direct-acting, TIC is reverse acting, and controller algorithm is feed-forward.
D. Valve is fail closed, PIC is reverse-acting, TIC is reverse acting, and controller algorithm is cascade.
- A temperature SAC is not responding well to disturbances in the steam flow. What is done to repair the problem?
A. Install a temperature primary and flow secondary cascade loop.
B. Install a flow primary and temperature secondary cascade loop.
C. Increase the filter time on temperature measurement.
D. Increase the filter time on the flow signal.
- A stand-alone pneumatic controller will not respond to any changes in input measurement. The output remains at full scale. What is the cause?
A. Plugged amplifier.
B. Loss of air supply.
C. Plugged nozzle.
D. Proportional band set too high.
- A PLC installation requires 33 limit switches and 33 solenoids. How many 8-channel discrete input cards and 16-channel discrete output cards are required?
A. 3 input and 3 output.
B. 3 input and 5 output.
C. 5 input and 3 output.
D. 5 input and 5 output.
- An online change is made to a PLC program. What is the backup procedure?
A. Save program to backup file and upload from PLC.
B. Save program to backup file and download to PLC.
C. Upload from PLC and save program to backup file.
D. Download to PLC and save program to backup file.
- __________
- __________
- On a redundant PLC installation, the secondary processor fails. What is done?
A. Replace secondary PLC processor, replace communications card, restart secondary PLC, then verify operation.
B. Replace secondary PLC processor, restart secondary PLC, transfer primary processor program into secondary processor, then verify operation.
C. Replace secondary PLC processor, restart secondary PLC, transfer secondary processor program into primary processor, then verify operation.
D. Replace secondary PLC processor, restart secondary PLC, load program into secondary PLC through programming laptop, then verify operation.
- Data is not being transferred between modules in a PLC rack. Where is the fault located?
A. __________
B. __________
C. __________
D. __________
- Refer to Figure 55. The heater does not come on and the fan is running continuously. What is the cause?
A. Heater circuit is latched.
B. Fan circuit will not latch.
C. Temperature switch has failed open.
D. Temperature switch has failed closed
- At which point are signal cable shields terminated in a DCS cabinet?
A. Isolated instrument ground bus.
B. Instrument ground bus.
C. Isolated system ground bus.
D. System ground bus.
- What are the steps to change the configuration of a control module on an operational DCS?
A. Make changes to the file on the online database, save to the online database, then transfer the file to the online database.
B. Make changes to the file on the online database, save to the offline database, then transfer the file to the online database.
C. Transfer the file from the online database, make changes using the configuration software, save to the offline database, then transfer the file to the online database.
D. Transfer the file from the offline database, make changes using the configuration software, save to the online database, then transfer the file to the online database.
- What is the configuration procedure when connecting a PLC to a DCS?
A. Connect the PLC to the DCS, then connect the gateway to the DCS.
B. Connect the PLC to the DCS, then connect the gateway to the PLC.
C. Connect the PLC to the gateway, then connect the gateway to the DCS.
D. Connect the PLC to the HMI, then connect the DCS to the power supply.
- What regular maintenance is required on a DCS when it is in operation?
A. Remove dust accumulation, change cabinet filters, verify cooling fan operation and perform backups.
B. Remove dust accumulation, tighten terminals, change cabinet filters and update software.
C. Change configuration, change cabinet filters, verify cooling fan operation and update software.
D. Change configuration, tighten terminals, change cabinet filters and perform backups.
- A DCS control loop operates in MANUAL, but when placed in AUTO, the controller output goes to minimum. Process variables suggest that the output should be increasing. What is the cause?
A. The proportional gain is set too high.
B. The algorithm is experiencing reset windup.
C. The controller action specified is incorrect.
D. The control algorithm has failed.
- The original design shows an HMI is to be installed in an area of high vibration. Which action is taken?
A. Secure the HMI on a structural beam.
B. Change HMI refresh rate to vibration frequency.
C. Install the HMI
D. __________
- An HMI graphic is being configured to indicate two valves.
- Valve 1 tag is improperly addressed.
- Valve 2 tag correctly addressed.
If the status of valve 1 is changed, what error results on the HMI?
A. Valve 1 graphic changes animation and valve 1 status changes.
B. Valve 2 graphic changes animation and valve 2 status does not change.
C. Valve 2 graphic does not change animation and valve 2 status changes.
D. Valve 1 graphic does not change animation and valve 1 status does not change.
- Two motors operate independently. When attempting to run motor 1 from the __________
A. __________
B. __________
C. __________
D. __________
- How are remote sites connected to the central control room on a SCADA system?
A. By running bus connections between two PLC’s.
B. By installing and implementing a wireless network.
C. By linking transmitters to workstations using fiber optic cable.
D. By connecting multiple workstations using cabled data highways.
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Section 1 COMMON OCCUPATIONAL SKILLS7
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Section 2 PROCESS MEASURING AND INDICATING DEVICES35
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Section 3 SAFETY AND SECURITY SYSTEMS AND DEVICES9
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Section 4 HYDRAULIC, PNEUMATIC AND ELECTRICAL SYSTEMS10
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Section 5 FINAL CONTROL DEVICES24
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Section 6 COMMUNICATION SYSTEM AND DEVICES14
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Section 7 CONTROL SYSTEMS AND PROCESS CONTROL26
