Practice Test Geeks(CPT) Certified Process Technician Practice Test
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Advanced Diagnostics & Troubleshooting Flashcards

7 cards from real CPT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Advanced Diagnostics & Troubleshooting flashcards as text

  1. A level transmitter using a differential pressure cell reads low level when the actual level is high. Which fault is MOST likely?

    Answer: High-side impulse line is plugged

    A plugged high-side impulse line prevents high pressure from reaching the transmitter, causing it to report a lower level than actual.

  2. A reciprocating compressor shows increased vibration on every other stroke. The MOST likely cause is:

    Answer: A faulty suction or discharge valve on one cylinder

    A faulty valve on one cylinder causes unequal loading between cylinders, producing vibration that repeats every other stroke.

  3. When performing a loop check on a 4-20 mA transmitter, a technician measures 4 mA at 0% and 19.5 mA at 100%. This indicates:

    Answer: Span error only

    The zero (4 mA at 0%) is correct but the span is short (19.5 mA instead of 20 mA at 100%), indicating a span calibration error only.

  4. A process vessel pressure is rising unexpectedly with no increase in feed rate or temperature. Which cause should be investigated FIRST?

    Answer: Blocked vent or relief path

    An unexpected pressure rise with constant inputs most urgently points to a blocked vent or plugged relief valve preventing normal pressure release.

  5. During troubleshooting, a technician uses a step test by making a step change to the controller output in manual mode. The primary purpose is to:

    Answer: Verify the final control element moves as expected and measure process response

    A step test confirms valve stroke response and reveals the open-loop process gain, time constant, and dead time needed for tuning diagnostics.

  6. A pump discharge pressure is normal but flow is lower than expected. The MOST likely cause is:

    Answer: Partially closed discharge valve

    A partially closed discharge valve restricts flow while maintaining or elevating discharge pressure, matching the observed symptoms.

  7. A thermocouple reads erratically and the signal drops to a very negative value intermittently. The MOST probable fault is:

    Answer: Open circuit or broken thermocouple wire

    An open circuit in a thermocouple causes the input to float, often driving the transmitter to a downscale (very negative) burnout indication.