Answer / sam

You can install the PT anywhere on the pipe. It is best to
install on top in crude and slurry application but to
measure water you can install any where, even under the pipe.
If you install on the side or under the pipe fill the
impulse line with water then do a zero on the PT before you
do the final span calibration. Also remember that the
calibration you do on the PT must be exactly the same as to
what your DCS or SCADA faceplate have been scaled to. In
other words if you calibrate the PT for 0 to 20Bar you must
make sure the faceplate in the CCR are also scaled to 0 to
20bar.
Good luck

Answer / carl_ellis

If the transmitter is not directly mounted on the
underground pipe, which is not unusual unless there is
vault access, then an impulse tube/pipe has to come up out
of the ground. The pressure measurement will be in error,
low, by the difference in elevation between the pipe's
elevation and the pressure transmitter's elevation.

Suppose the pipe is 2.1m below the grade level and the
pressure transmitter is 1.6m above grade. The elevation
difference is 3.7m.

The measurement is 3.7m or 0.362 bar low.

It is not unusual to have water supplied at pressure
between at 4-8 bar. At 4 bar pressure, an error of 0.36m
water column is a 9% error, a vary large value for an
insturment capable of 0.25% or better accuracy.

The commissioning of the unit should include the
appropriate zero correction to compensate for such a large
error.

Carl Ellis, Measure First

what is diff b/w neutron and ground?

3 Answers  

---

If I want to buy a pressure switch & 3-way valve for hot water application then witch parameter I should consider.

1 Answers  

---

why we use impulse line of flow transmitter at 45 deg. angle both side of orifice plate.

0 Answers  

---

How to calibrate capillary type level transmitter

0 Answers  

---

Pressure transmitter working Principles?

1 Answers  

---

what are procedure of sox-nox calibration

0 Answers   TATA,

---

Guy's need your support,I want to measure closed tank level which is under vacuum -630mmHg using DP Transmitter, tank fluid density 1.38, Tank height is 7ft

4 Answers   icl,

---

What are SMART insuments?

5 Answers  

---

what is the thermocuple compensation circuit

3 Answers  

---

how to calibrate load cell

0 Answers   Siemens,

---

what is loop1 and loop2 in MTS LT?

0 Answers   SPGC,

---

What is the difference between fire detector and smoke detector?

5 Answers  

---