Answer / venbha123

If the LP leg of the transmitter is kept dry, steam may get condensed in the LP leg because of which the level indication may be wrong. Hence We are using wet leg for LP side of the transmitter, which is initially filled with pure water. When the drum is at zero level, the pressure difference is only the head pressure acting on the LP side - that is 100% level head at LP side. Normally in DP transmitter the HP side pressure will be more than the LP side. In this case since the pressure in the LP side is more than the pressure in HP side the range is mentioned as negative. At 100% level both the head pressures at HP & LP are the same, the DP becomes zero. Therefore the range is mentioned as: from negative value to zero.

Answer / ayaz

IN CLOSE VESSEL/DRUM
we use wet leg mean(low impulse line fill with same liquid)
we know that our measurement is when right then dp is creat
and when we use without low side filling  and hp side only pressure the steam create pressure on lp side so dp not create and show wrong indication
so we use fill lp side pressure and address in negative and when hp side posative or actual pressure create a dp in right indication will show

What is Cavitation in a control valve?

0 Answers   CCIE, KN,

---

what will be the output of the temparature transmitter if temp is 120 degre celcius.

1 Answers   Base Automation, NTPC, PDO,

---

hi this is noor i wnt know the procedure and precations errection for PRESSURE AND DP transmitters? how to take impusle line for level and flow?(water and steam) impulse line sizes? and type of material ? plz give me answer / reffer any website ? to me "mail2noor.hyd@gmail.com"

1 Answers  

---

WHAT IS SELF CLEAN ELCTRODE IN MAGNETIC FLOWMETER?? WHAT DO YOU MEAN BY THIS TERM??

2 Answers   IOCL,

---

We have ZR22G-100-S-A-E-T-T--E-A/CV/F1 Model Zirconia Oxygen analyser which is Yokogawa make. I kept the analyser in Flue gas path at Air pre heater area. My plant is 7.5MW Biomass power plant. For a particular fuel, Coconut Husk which contains Sodium and Potassium chlorides iam not getting proper reading, Analyser output always Zero. I calibrated the analyser and it is OK. For Other fuels like Wood chips, Cholam waste, DOB, Groundnutshells, Ply wood waste and all iam getting actual percentage of Oxygen. What is the main reason behind this draw back?

2 Answers  

---

HELLO FRIENDS plz tell me which are the PROTOCOLS we are using in PLC

3 Answers  

---

how to explain PID?

2 Answers   Jindal,

---

can we replace a slot sensor (inductive type) with limit switch (potenial free contact / no-nc type).

0 Answers   Max India,

---

I want measure the volumetric flow of gas in waste heat recovery Boiler?Tell me how and which type of instruments required. Plz mail me:naba02222@gmail.com Sam please post the answer .

0 Answers  

---

Which products are available in the Mass Systemswitch and System Manager AC range?

0 Answers  

---

What are primary elements of measuring pressure?

0 Answers  

---

dear sir we have insatlled positioner model no.sipart PS2 make Siemens at our control valves . now problem is if we want to increase the response of valve opening speedy /fast. what parameters do we change for positioner ? any idea. please guide us.

0 Answers   CPL,

---