Question 556General Subjects - Assistant Engineer

70% to pass

For a pneumatic transmission system for instrumentation purposes, if a pneumatic pressure indicator has a calibrated scale of 0 to 1000 psig, what would be the actual measured pressure if the transmitted pneumatic signal pressure to the indicator is 9 psig, assuming the industry standard of 3 to 15 psig is used for instrument air?

A300 psig
B500 psig
C600 psig
D750 psig
AI Explanation

The correct answer is B) 500 psig. The standard pneumatic signal range for instrumentation is 3 to 15 psig. Since the pressure indicator is calibrated from 0 to 1000 psig, and the transmitted pneumatic signal is 9 psig, this would correspond to 500 psig on the indicator's scale. This is because the 3 to 15 psig signal range is linearly mapped to the 0 to 1000 psig scale of the indicator. The other options are incorrect because they do not accurately reflect the linear scaling of the 3 to 15 psig signal range to the 0 to 1000 psig indicator scale.

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