Answer / vijay

close the hp and lp valve and drain the water then open the
vent valve it should show the zero value.

Answer / jayaram

1.close the both HP and LP rootvalves
2.open the both HP and LP drain valves to drain the service
completely.
3.Close the drain valves.
4.open the vent caps of both HP and LP leadlines near the
rootvalves.
5.fill the lead lines completely with water.
6.obviously LP side , more pressure acts and current goes
below 4mA. So elevate the Zero Potentiometer to 4 mA(this
is for analog standard dp transmitter).
7.first of all you have to calibrate the dp transmitter for
the required range, then only you can do this elevation
zero checking.

Answer / altamash

close the both valve ie LP & HP then drain the water and then open the vent of LP then connect the HART and do the zero trim by HART then we can find ZERO

Answer / vishal

Just open the equilizer valve and u will get zero
No need to open or close any other valve
Check by multimeter

Answer / suresh agravat,jamnagar

first close the rootvalve then drain trhough needle velve
then close both LP and HP isolated valve and open equliser
valve

Answer / muhammad yasir

close HP isolation valve open HP side drain valve.Transimiter read maximum Differential pressure and Transimiter show O% Level or 4ma because LP lmpluse line liqued act pressure on LP side Transimiter.
When span check close both HP and LP side valves and open drain valve Transimiter read 0 differential pressure.Transimitter show 100% level or 20ma.

Answer / faiyaz ahmad

first open the equalizing and then close the isolation valve and open the vent valve both side and make it zero in this condition transmitter will show zero.

I work on a electronic positioner transmitter 4211 at the field.I connect my multimeter in series to get the current output then I calibrate it to 4ma in 0% of position of the valve and 20ma in 100% position of the valve.My problem is in the field I get the correct output current based on my multimeter but in the dcs they only receive 40% in a output 20ma of this positioner.Then I try to simulate in this analog card and they receive the equivalent percent on the value that I simulated.Is ther any possibility to reset the zero and span of this positioner 4211 fisher.And what other possibility I can do to fixed this.This is my email add ( landicho_randy@yahoo.com )

4 Answers  

Explain about 4 wire instrument concept & tell about its wiring fron sensor in Field to PLC panel.Explain with an example?

3 Answers   IOCL,

How can i copy program (parameter) from mm440 (V.F.D.) by using BOP?

0 Answers  

Control valve Flow characteristic. How the equal percentege curve form?

5 Answers  

Pl send the model question paper of mahagenco account officer post

0 Answers   MahaGenco,

suppose, after calibrating a transmitter we fixed it in a process line. At live zero condition the Tx shows 4.5 mA. what should we do to make the Tx show 4 mA? If we adjust zero, will it not affect the calibration?

4 Answers   ABG Shipyard,

In dcs contol valve parameters showing like this Gain=1 or 2 , ti=7 sec, td=20sec. But temp,pressure,level control valves we are using in which type parameter side using ti,td clearly tell me

1 Answers  

i have a dp tx range is 5000mmwc. in which calibration i use in a open tank.1.5*3.5*2.5 mtr.for level msmnt. what is the calculation.

2 Answers   Bajaj Hindusthan,

What is the difference between ROM & RAM .

1 Answers   Sabic, SPIC,

How to Calibrate Interface Level Troll in field

0 Answers  

What are the key features of a Distributed Control System? describing the various layers (sensor through to business system interfaces) as well as the hardware, software and security aspects of the DCS.

0 Answers  

i need some objective type questions in instrumentation

0 Answers