Instrumentation & Control interview questions
500 questions with model answers, in four levels. Start with Basic, check yourself honestly, then move up.
Basic questions
- Measurement Fundamentals & Errors (13)
- Sensors & Transducers (13)
- Temperature & Pressure Measurement (13)
- Flow & Level Measurement (13)
- Signal Conditioning & Data Acquisition (13)
- Control System Theory (13)
- PID Control & Tuning (12)
- Stability Analysis (Root Locus, Bode, Nyquist) (12)
- PLC Programming (12)
- DCS & SCADA (12)
- Industrial Communication (HART, Modbus, Profibus, Fieldbus) (12)
- Control Valves & Safety Instrumented Systems (12)
Intermediate questions
- Measurement Fundamentals & Errors (13)
- Sensors & Transducers (13)
- Temperature & Pressure Measurement (13)
- Flow & Level Measurement (13)
- Signal Conditioning & Data Acquisition (13)
- Control System Theory (13)
- PID Control & Tuning (12)
- Stability Analysis (Root Locus, Bode, Nyquist) (12)
- PLC Programming (12)
- DCS & SCADA (12)
- Industrial Communication (HART, Modbus, Profibus, Fieldbus) (12)
- Control Valves & Safety Instrumented Systems (12)
Advanced questions
- Measurement Fundamentals & Errors (10)
- Sensors & Transducers (10)
- Temperature & Pressure Measurement (11)
- Flow & Level Measurement (11)
- Signal Conditioning & Data Acquisition (10)
- Control System Theory (10)
- PID Control & Tuning (11)
- Stability Analysis (Root Locus, Bode, Nyquist) (11)
- PLC Programming (10)
- DCS & SCADA (10)
- Industrial Communication (HART, Modbus, Profibus, Fieldbus) (10)
- Control Valves & Safety Instrumented Systems (11)
Tricky questions
- Measurement Fundamentals & Errors (6)
- Sensors & Transducers (6)
- Temperature & Pressure Measurement (7)
- Flow & Level Measurement (7)
- Signal Conditioning & Data Acquisition (6)
- Control System Theory (7)
- PID Control & Tuning (6)
- Stability Analysis (Root Locus, Bode, Nyquist) (6)
- PLC Programming (6)
- DCS & SCADA (6)
- Industrial Communication (HART, Modbus, Profibus, Fieldbus) (6)
- Control Valves & Safety Instrumented Systems (6)
Sample questions
- What is the difference between accuracy and precision?
- What is a tachogenerator?
- What is a radar level transmitter?
- What is a second-order system?
- What is a minimum-phase system?
- What is a faceplate in a DCS display?
- How is accuracy expressed for an instrument?
- What is a vibration sensor's frequency response limitation?
- How does guided wave radar differ from non-contact radar?
- What is a FOPDT model?
- How is phase margin related to damping ratio?
- What is time synchronization important for in SCADA?
- A pressure loop has transmitter error ±0.10%, calibrator uncertainty ±0.05% and ambient temperature effect ±0.08% of span. What is the combined uncertainty?
- What problems do impulse lines cause, and how are they mitigated?
- What are the NAMUR NE 43 signal levels?
- Find the phase margin of L(s) = 10/(s(s + 1)).
- What is the trade-off in historian data compression?
- A digital meter shows five decimal places, so it must be very accurate. True?
- A larger flow meter is safer because it has spare capacity. Right?
- Higher bandwidth is always better. True?