ISA Certified Control Systems Technician
(CCST) Level II Practice Exam Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
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Subjects Covered: Process Measurement, Control Systems, Final Control
Elements, Digital Systems, and Troubleshooting
1. A 4–20 mA signal represents a process range of 0–100 psi. What
pressure corresponds to a 12 mA signal?
a) 25 psi
b) 50 psi
c) 60 psi
d) 75 psi
Rationale: 12 mA is halfway between 4 and 20 mA, so it represents
50% of the range, which is 50 psi.
,2. What is the purpose of a transmitter in a control loop?
a) To receive data from a controller
b) To control the final control element
c) To convert a process variable into a standardized signal
d) To store historical process data
Rationale: A transmitter measures a process variable and sends a
proportional signal (e.g., 4–20 mA) to a controller.
3. A thermocouple produces a voltage signal that depends on:
a) Resistance changes
b) Pressure differences
c) Temperature differences between junctions
d) Flow rate
Rationale: Thermocouples generate a voltage proportional to the
temperature difference between the hot and cold junctions.
4. What does PID stand for in a controller?
a) Process, Instrument, Display
b) Proportional, Integral, Derivative
c) Pressure, Indicator, Display
d) Position, Input, Delay
Rationale: PID represents the three modes of control used in
feedback loops: proportional, integral, and derivative.
5. What is the main function of a control valve positioner?
a) To limit valve movement
, b) To amplify pneumatic signals
c) To ensure valve position corresponds to the control signal
d) To measure valve stem position
Rationale: A positioner adjusts air pressure to ensure the valve stem
accurately follows the controller signal.
6. In a current loop, what happens if the loop resistance increases?
a) The signal current increases
b) The signal current decreases
c) The voltage at the transmitter increases
d) The loop becomes unstable
Rationale: Increased resistance causes a voltage drop, reducing loop
current if voltage supply is limited.
7. What type of control action eliminates steady-state error?
a) Proportional
b) Integral
c) Derivative
d) Feedforward
Rationale: Integral action continuously sums the error over time,
eliminating offset.
8. What device converts a pneumatic signal to an electrical signal?
a) I/P transducer
b) P/I transducer
c) Controller
, d) Positioner
Rationale: A P/I transducer converts pneumatic (pressure) signals
into electrical signals.
9. A flow transmitter calibrated 0–100 GPM gives 12 mA output. What is
the flow rate?
a) 25 GPM
b) 50 GPM
c) 75 GPM
d) 100 GPM
Rationale: 12 mA is 50% of span; 50% of 100 GPM equals 50 GPM.
10. What is the purpose of a 250-ohm resistor in a 4–20 mA loop?
a) To reduce loop voltage
b) To convert current to voltage for monitoring (1–5 VDC)
c) To increase loop current
d) To isolate loop grounds
Rationale: A 250-ohm resistor converts 4–20 mA to 1–5 V for input to
devices requiring voltage signals.
11. What is the output of an RTD proportional to?
a) Resistance
b) Voltage
c) Current
d) Temperature difference
(CCST) Level II Practice Exam Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
Download Pdf
Subjects Covered: Process Measurement, Control Systems, Final Control
Elements, Digital Systems, and Troubleshooting
1. A 4–20 mA signal represents a process range of 0–100 psi. What
pressure corresponds to a 12 mA signal?
a) 25 psi
b) 50 psi
c) 60 psi
d) 75 psi
Rationale: 12 mA is halfway between 4 and 20 mA, so it represents
50% of the range, which is 50 psi.
,2. What is the purpose of a transmitter in a control loop?
a) To receive data from a controller
b) To control the final control element
c) To convert a process variable into a standardized signal
d) To store historical process data
Rationale: A transmitter measures a process variable and sends a
proportional signal (e.g., 4–20 mA) to a controller.
3. A thermocouple produces a voltage signal that depends on:
a) Resistance changes
b) Pressure differences
c) Temperature differences between junctions
d) Flow rate
Rationale: Thermocouples generate a voltage proportional to the
temperature difference between the hot and cold junctions.
4. What does PID stand for in a controller?
a) Process, Instrument, Display
b) Proportional, Integral, Derivative
c) Pressure, Indicator, Display
d) Position, Input, Delay
Rationale: PID represents the three modes of control used in
feedback loops: proportional, integral, and derivative.
5. What is the main function of a control valve positioner?
a) To limit valve movement
, b) To amplify pneumatic signals
c) To ensure valve position corresponds to the control signal
d) To measure valve stem position
Rationale: A positioner adjusts air pressure to ensure the valve stem
accurately follows the controller signal.
6. In a current loop, what happens if the loop resistance increases?
a) The signal current increases
b) The signal current decreases
c) The voltage at the transmitter increases
d) The loop becomes unstable
Rationale: Increased resistance causes a voltage drop, reducing loop
current if voltage supply is limited.
7. What type of control action eliminates steady-state error?
a) Proportional
b) Integral
c) Derivative
d) Feedforward
Rationale: Integral action continuously sums the error over time,
eliminating offset.
8. What device converts a pneumatic signal to an electrical signal?
a) I/P transducer
b) P/I transducer
c) Controller
, d) Positioner
Rationale: A P/I transducer converts pneumatic (pressure) signals
into electrical signals.
9. A flow transmitter calibrated 0–100 GPM gives 12 mA output. What is
the flow rate?
a) 25 GPM
b) 50 GPM
c) 75 GPM
d) 100 GPM
Rationale: 12 mA is 50% of span; 50% of 100 GPM equals 50 GPM.
10. What is the purpose of a 250-ohm resistor in a 4–20 mA loop?
a) To reduce loop voltage
b) To convert current to voltage for monitoring (1–5 VDC)
c) To increase loop current
d) To isolate loop grounds
Rationale: A 250-ohm resistor converts 4–20 mA to 1–5 V for input to
devices requiring voltage signals.
11. What is the output of an RTD proportional to?
a) Resistance
b) Voltage
c) Current
d) Temperature difference
