Question { 8395 }

what is meant by calibration

Answer

Calibration is matching of the standard value of
instrumentation. Which gives Instrument society
of America (ISA) in 1968. Or matching of the value of
master (True) Instrument. 4 mA to 20 mA
3 PSI to 15 PSI, 0 % to 100 % etc.

Question { Nirma, 25192 }

what is control valve input and out put

Answer

Input- 4-20mA
Output- 3-15psi

Question { IPCL, 9979 }

what is thermocouple output

Answer

millivolt DC

Question { 11389 }

what are the pinciples & units of flow, level, temperature,
pressure, quality.

Answer

Unit of flow:kg / hr, litter / min, gallon / min, m3 / hr,
Nm3 / hr. (Gases)

Unit of level: Meters, mm, cm, percentage.

Unit of temerature: Degree Centigrade, Degree Fahrenheit,
Degree Kelvin, Degree Rankin.

Unit of pressure: bar, Pascal, kg/cm2, mm Wg, mm hg,

Question { IOCL, 51222 }

how can we caliberate interface
level troll

Answer

Interface level troll means: When a vessel is filled with
two liquids of two different specific gravities the level
measurement refers to as interface level.
DP = H (D - d)


Calculation # 1 If the calibrating liquid is water:
Process Liquid Density / 1* Displacer height = mm of H2O.

Calculation # 2 If the calibrating liquid is other liquid:
Process Liquid Density / Calibrating liquid density *
Displacer height = mm of H2O. (Calibrating liquid height in
mm).


1. First close both the primary isolation valves and drain
the liquid inside the chamber.
2. Adjust the zero to get 0% output.
3. Connect a transparent PVC tube to the drain point as
shown in hook up.
4. Fill it to the center of the top flange.
5. Adjust the specific gravity or span adjustment
(Electronic Level).
6. Fill it up to 50 %, check linearity.

40. How will you calibrate on interface level control. ?
On an interface leveltrol there are two liquid of two
different specific gravities.
1. The level will be zero when it is full of lighter liquid.
Zero % level = H X d.
H = Displacer length
d = Specific gravity of lighter liquid.
2 The level will be 100 % when it is full of heavier liquid.
100 % level = H X D.
D = Specific gravity of heavier liquid.
Calibration with water:
1. Fill H X d level with water adjust zero.
2. Fill H X D level with water adjust Sp. gravity or span.
3. Check linearity.

Displacer length: L in mm
Density Low : dl in Kg / 1
Density High : DH in Kg / 1
Alarm / Trip point %: X
HH Trip Point: Y in mm

Question { 26563 }

how many type of control valve?

Answer

Globe valve, Butterfly valve, Gate valve, Diaphergm valve,
Ball valve, Knife Edge valve, Angle valve, Three way valve,
Twoway valve.