Pressure Measurement Instruments

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What is the primary purpose of the porcelain insulator in a resistance thermometer?

To amplify the temperature signal from the platinum wire
To provide mechanical support to the platinum wire
To provide electrical insulation between the platinum wire and the metal sheath (correct)
To increase the thermal conductivity of the instrument

What is the effect of temperature change on the platinum wire in a resistance thermometer?

It increases the wire's resistance proportionally (correct)
It decreases the wire's resistance
It changes the wire's resistance randomly
It has no effect on the wire's resistance

What is the temperature range of a resistance thermometer?

-200 to 650°C (correct)
500 to 1000°C
20 to 100°C
0 to 200°C

What is the advantage of a resistance thermometer over other temperature measurement instruments?

High accuracy and fast response (D) Signup and view all the answers

What is the principle behind the working of a thermocouple?

Thermoelectric effect (D) Signup and view all the answers

What is the primary material used in the construction of the C-type Bourdon tube pressure gauge?

Phosphor bronze (B) Signup and view all the answers

What is the disadvantage of using a bridge circuit with a resistance thermometer?

Result in slight inaccuracy due to current flowing through the bridge circuit (B) Signup and view all the answers

What is the purpose of the linkage and lever mechanism in the C-type Bourdon tube pressure gauge?

To operate the pointer (D) Signup and view all the answers

What happens to the shape of the Bourdon tube when the fluid under pressure enters it?

It changes from oval to circular (A) Signup and view all the answers

What is the purpose of the multiplication adjustment in the Bourdon tube?

To match the linear tip movement with the rotational pointer movement (A) Signup and view all the answers

What is the effect of a shorter lever on the Bourdon tube's operation?

It increases the rotation of the pointer for the same amount of tip travel (B) Signup and view all the answers

How is the pressure connection made in the C-type Bourdon tube pressure gauge?

Through a socket at the base of the tube (B) Signup and view all the answers

What is the primary function of a strain gauge?

To convert mechanical displacement into a change of resistance (B) Signup and view all the answers

What is the purpose of a Wheatstone bridge in a strain gauge circuit?

To convert the resistance change into a voltage (D) Signup and view all the answers

What is the difference between bonded and unbonded strain gauges?

Bonded strain gauges are attached to a structure, while unbonded strain gauges are not (A) Signup and view all the answers

What happens to the wire in a bonded strain gauge when the surface is disturbed?

The resistance of the wire changes (B) Signup and view all the answers

What is the limitation of the armature movement in an unbonded strain gauge?

It can move only in one direction (B) Signup and view all the answers

What is the material used to bond the paper sheet to the structure in a bonded strain gauge?

Adhesive material (C) Signup and view all the answers

What is the function of the LVDT in the given setup?

To convert ring deflection into a voltage signal (C) Signup and view all the answers

How do the strain gauges in the strain gauge load cell react to the applied force?

They decrease in length and increase in cross-sectional area (A) Signup and view all the answers

What is the purpose of the Rtc in the strain gauge load cell?

To compensate for the difference in temperature coefficient of resistance of four strain gauges (D) Signup and view all the answers

What is the advantage of LVDTs mentioned in the text?

They have relatively high output signal levels and high accuracies (D) Signup and view all the answers

What is the function of the external bosses A and B in the given setup?

To apply force to the ring (C) Signup and view all the answers

What is the purpose of the balancing of the Wheatstone bridge in the strain gauge load cell?

To provide a linear output voltage with respect to the applied force (D) Signup and view all the answers

What is the main reason for converting analog signals to digital signals?

To facilitate processing by the microcontroller (C) Signup and view all the answers

Which type of ADC is commonly used in general-purpose industrial applications?

Successive approximation (A) Signup and view all the answers

What is the primary function of an analog-to-digital converter (ADC)?

To convert analog signals to digital signals (C) Signup and view all the answers

What is the characteristic of analog signals in terms of their range of values?

Infinite range of values (D) Signup and view all the answers

What is the purpose of the 'Wait' step in the analog-to-digital conversion process?

To allow the voltage to stabilize (C) Signup and view all the answers

Which of the following is an example of a physical signal that is typically analog?

Temperature (A) Signup and view all the answers