Pressure Measurement Instrumentation Question Answers

Pressure Measurement Instrumentation Question Answers

Q1. A transmitter calibrated to measure water level in a tank is indicating 50% level. Instead of water, if the same tank is filled with  a liquid having a specific gravity of 0.8, to the same level, then the level indicated by the transmitter (without changing the calibration) 

1. will be more
2. will be less
3. will be same
4. will be unpredictable

Q2. What is the pressure equivalent of 14.7 psi in inches of H₂O ? (Use the table)

1. 0.53 in H₂O
2. 29.93 in H₂O
3. 101.283 in H₂O
4. 407.6 in H₂O

Q3. In a 0-100 psig pressure gauge , the zero actually represents

1. Absolute zero pressure
2. Vacuum pressure
3. 14.7 psia

Q4. How many process connections do differential pressure instruments have ?

1. One
2. Two
3. Three
4. Four

Q5. For better accuracy, adjustments such as zeroing a pointer should be made  with __________ pressure applied to the gauge.

1. No
2. Midscale
3. Maximum

Q6. The purpose of a pulsation damper (Snubber) in a pressure gauge is

1. To dampen pulsations
2. To block the process from entering the pressure gauge
3. To avoid corrosion
4. To give more strength

Q7.  In the figure, how much head correction is to be made in the pressure gauge ?

1. Pressure equivalent to 20 ft
2. Pressure equivalent to 5 ft
3. Pressure equivalent to 15 ft
4. Pressure equivalent to 25 ft

Q8. In a strain gauge sensor ___________ varies when pressure applied.

1. Temperature
2. Milli volt
3. Capacitance
4. Resistance

Q9. The resistance across the terminals of an open pressure switch will be

1. infinity
2. Zero
3. Very low
4. low

Q10. What is the maximum recommended rotation angle for Yaokogawa transmitter

1. 90
2. 180
3. 270
4. 360

Q11. Identify the service  for the following three cases in the figure

1. Gas, Liquid, Steam
2. Steam, Gas, Liquid
3. Liquid, Gas, Steam
4. Liquid, Steam, Gas

Q12. For liquid measurement, slope the impulse piping at least 1 inch per feet upward  from ___________ and towards the __________________

1. Transmitter, Process connection
2. Process connection, Transmitter

Q13. One of the purpose of filling glycerin in a pressure gauge is to slow the action of the pointer across the scale.

(True or false )

Q14. In a variable capacitance pressure transmitter, the isolating diaphragms will not be in contact with the process or reference pressure. Is this statement true or false?

1. True
2. False

Check the Answers 

Y3

Q15. Show the polarity of the power supply terminals below.

Q16. Find the pressure acting on the surface  by weight A and weight B.

ANS:  P = F/A  =   50/50 =  1 lb/in2

            P = F/A  =   50/1 =  50 lb/in2

Q17. If  H= 25 inches, what is the  pressure indicated by the Gauge in the figure ?

P=H  *  SG

Q18. Name the pressure element 

ANS: BELLOWS

Q19.  What is the purpose of using a pigtail siphon with a pressure gauge in steam application ?

Answers: 

To prevent diaphragm damage from steam high pressure.

Q20. Give one reason for  using a remote  seal in a pressure transmitter ?

 ANS:1.TO AVOID TRANSMITTER DIRECTLY CONTACT WITH PROCESS FLUID.

2.FOR REMOTE MEASUREMEENT

Q21. In  gas service the transmitter is mounted above the process line. Why?

ANS:IF IMPULSE TUBING HAVING CONDENSATE IT WILL AFFECT TRANSMITTER,THEN IF YOU PUT TRANSMITTER ABOVE THEN CONDENSATE FALLS DOWN.

Q22. What is the purpose of using equalization valve in a 5 valve manifold?

TO BALANCE THE PRESSURE BETWEEN HIGH AND LOW SIDE

Q23. If the Burnout switch position is High , what will be the value of output mA?

ANS:  HIGH:21.6mA             LOW:3.2 mA

Q25. What is the purpose of using non-hardening sealant ?

https://www.youtube.com/watch?v=ZW3O7blRnWk

https://www.youtube.com/watch?v=6TVKO5NzfSU

https://www.youtube.com/watch?v=C6kx4HA7MXw