Instrumentation NCCER ALL 350 QUESTIONS AND VERIFIED SOLUTIONS LATEST UPDATE THIS YEAR

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Instrumentation NCCER ALL 350 QUESTIONS
AND VERIFIED SOLUTIONS LATEST UPDATE
THIS YEAR


QUESTION: What is the final step in commissioning; what should be the final step? - ANSWER-

gathering all the documentation




QUESTION: In reference to PID controller, reset relates to which variable? - ANSWER-reset or

integral provides an output that is proportional to the time integral of the input. Eliminates

offset.




QUESTION: An employee deenergizes a piece of equipment by removing the power plug from

the outlet, if the employees continue to hold the power plug once removed. The employee is

said to have


what type of control over the energy potential? - ANSWER-exclusive control




QUESTION: The output of a thermocouple is expressed in what units? - ANSWER-milli volts (mV)




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QUESTION: A differential pressure transmitter mounted on a non-vented tank is used to

measure the _______ of the vessel? - ANSWER-level




QUESTION: When properly calibrated and installed the most accurate primary flow element is

the ________? - ANSWER-venturi tubes




QUESTION: What is the primary disadvantage of a direct operated regulator? - ANSWER-non

adjustable




QUESTION: What is the advantage of a pilot operated regulator? - ANSWER-The pilot regulator

typically includes proportional band adjustments for verifying the sensitivity.




QUESTION: A valve has linear characteristic when __________. - ANSWER-flow rate provided is

proportional to the amount of value lift




When inspecting a regulator control nitrogen pad system on a large storage tank and no


pressure is found what critical item besides a regulator should be checked? - ANSWER-air

supply




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QUESTION: What type of service should Teflon paste never be used on? - ANSWER-service

oxygen lines. PTFE materials are not recommended for service on oxygen lines due to their

anaerobic nature.




QUESTION: A What is the principle behind how a solenoid valve opens? - ANSWER-it consists of

a valve body, a magnetic core attached to a valve stem, and a solenoid coil that works of

inductance.




QUESTION: Which of the following gasses should be used to purge tubing and pipe after

cleaning? - ANSWER-nitrogen




QUESTION: What type of input signal does a valve actuator receive from a V/P transducer? -

ANSWER-pneumatic signal




QUESTION: What does it mean to say that the controller is reverse acting? - ANSWER-decreases

the output signal when the measured medium increases




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QUESTION: What does it mean to say that a controller is direct acting? - ANSWER-increases its

output signal when the measure medium increases




QUESTION: How does fail open relate to air to close? - ANSWER-without the control medium, it

stays open; to close, the the control medium must be applied




QUESTION: What does the term fail open mean in relation to valve actuators? - ANSWER-




QUESTION: For a temperature of 1500F, what is a common gasket material? - ANSWER-ceramic

gaskets




QUESTION: Any person working near energized equipment during lockout tagout is considered

what type of


employee? - ANSWER-affected employee




QUESTION: What does P&ID's provide? - ANSWER-illustrates the operational layout of a system

including its piping valves, instrumentation and flow of a product




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