Smart Plant Instrumentation becomes a boon for process plants for easier operation and control of instruments for high yield from production.

1. SMART PLANT
INSTRUMENTATION
Presented by – D.CHAKRABORTY
C & I Power Plant , Email-
debyenduc@gmail.com

2. What is SMART

3. There are many definition of SMART in books and various journal but in
one word smart means Awesome (have all the qualities).
A person who has the qualities like – Good Looking , Hardworking ,
Good Communication Skill , Manners , Systematic , Disciplined , Good
Habits and Intelligent is called a smart person.
A SMART engineer in industry is defined by his/her five key qualities i.e.
S = Specific , M = Measureable , A = Achievable , R = Realistic , T =
Time Bound
The rapid craze in the field of instrumentation has changed the manual
process to automatic system and for doing that SMART instrumentation
are required.
Then what are the qualities should be there to make a instrument SMART.
Does all the above points are required to make an instrument SMART
(signal modulated auto ranging transducer).

4. Properties Of Smart Instruments
 Faster Communication
 Remote Communication
 Calibration & Configuration
 Easy Diagnostic
 Engineering Units
 Zero or Span Suppression
 Internal Data Protection
 Time Stamping
 HART (Highway Addressable
Remote Transducer)
Compatible
 Easy Programmable
 Integration with Network
Protocol

5.  Fast Communication – The various Ethernet control cable 2-wire or
4-wire system of signal loop made the data flow faster to the remote
host. The decoded signal are sent back to the transmitting controller as
a feedback with a speed more than 1 GBPS.
 Remote Communication – The remote communication by mean of
wireless or air bound telemetry are possible to access field instrument
in hazardous area & control by network server.
 Calibration & Configuration- All smart transducer are configured
with zero and span button as well as can be calibrate with industrial
master calibrator certified by NABL (national accreditation board for
testing and calibration).
 Easy Diagnostic – It have diagnostics that can detect faults in the
installation or problem with the application, each of which could
compromise measurement quality and reliability.
DESCRIPTION

6.  Zero & Span Suppression – The sudden deviation in reading
from actual , generate alarm in the graphical display , so that
engineer can check for any zero or span shift in the transmitter.
 Time Stamping – All the information flow are recorded in the
main server and can be accessed by trend view on graphical
display at the time of post fault occurrence.
 HART Compatible – All the smart transmitter are now HART
compatible , an engineer can fetch , modify and manipulate the
data after connecting it to the online instrument(transmitter).
 Real Time Control – They have the capability to control the data
online & if the system is made offline , the on feedback can be
forced , so that the interlock does not have any affect on other
equipment's.
DESCRIPTION

7. Success Story of SMART Instruments

8. Older Technology
Old Pneumatic Technology Disadvantages
 Slower operation of valve in case
of low pressure
 Every time need manual
adjustment
 May cause hunting in valve
 No Failsafe position
 Loss in air pressure due to frequent
bending and leakages
 Moisture in airline due to long
carryover by condensate
 Delay in process – Loss in
Production

9. Technological Improvement
New HART Based Technology Advantages
 Smoother operation
 No manual adjustment
 Rare hunting in valve
 Failsafe position Available
 Remote Control Available
 Feedback Available
 As per wish opening of valve
 0% - 4mA
 25% - 8mA
 50% - 12mA
 75% - 16mA
 100% - 20mA

10. VIEW OF SOME SMART INSTRUMENTS

11.  Two years ago, I was asked to look into the operation of a new
orifice plate flowmeter installation that does not involved pressure
and temperature compensation. The flowmeter was installed in a
power plant where two fluid of varied densities were being mixed
prior to being reacted. The problem cited was that the fluid were not
reacting properly and were not being added in the proper amounts to
achieve a good and complete feed to boiler due to different flow
velocities .
Then , I added a pressure and temperature sensor to the downstream
and upstream of the orifice plate respectively. Flow controllers were
used to control the fluid flows.
WHY COMPENSATION

12.  First and foremost, these flow measurement systems were not
compensated for pressure and temperature variations. The pressure
of the fluid from the source should be compensated because even
though it could easily be controlled, In this application, the
temperature of the gas varied with ambient conditions, thus
temperature compensation using a RTD or Thermocouple is must ,
so that flow errors of a few percent can be restricted easily.
Pressure & Temperature Compensation :-
𝝆 = 𝒎/𝑽 ,
where 𝝆 =
𝑷×𝑴𝒘
𝑹𝑻
… . . (𝟏){R= Gas Constant , Mw = Molecular Weight , V=
Volume , P= Pressure , m = Mass}
WHY COMPENSATION

13. 𝝆𝒓 =
𝑴𝒘
𝑹𝑻𝒓
× 𝑷𝒓……(2) {Since , Equ. (1)}
𝝆𝒅 =
𝑴𝒘
𝑹𝑻𝒅
× 𝑷𝒅……(3) {Since , Equ. (1)}
Operating with the formulas for real density and design density we can obtain the formula to
define the real density taking in account the pressure and temperature compensation.
Equating (2) & (3),
𝝆𝒓 =
𝑷𝒓×𝑻𝒅
𝑷𝒅×𝑻𝒓
× 𝑷𝒅 …… (4)
To obtain the DP Flow equation we will use two basic fluid mechanics equations : Euler’s
equation of continuity and Bernoulli’s principle to get the volumetric flow as -
𝑸𝒗=K
∆𝑷
𝝆𝒓
…….(5)
Put the value of (4) in (5) to get the compensated volume flow
𝑸𝒗=K
∆𝑷
𝑷𝒓×𝑻𝒅
𝑷𝒅×𝑻𝒓
×𝑷𝒅
{ Put this value to the DCS Logic while making program in FBD}
COMPENSATION CALCULATION

14. SMART CALIBRATION

15. CALIBRATION TECHNIQUES
Procedures
 Check for the upper & lower range
values of the transmitter.
 Ensure there should not be any leakages
from joints.
 Keep the Low side open to atmosphere.
 Connect the Communicator to + and –
sign (backside of transmitter).
 Connect a 250 ohms resistor in series
with dc power supply line.
 Apply pressure gradually in ascending
order and check the flow and mA in
communicator.
 Cross check the value with DCS display
to verify true 4-20 mA Analog output.
 Repeat the process while decreasing the
pressure and cross check.
 Note down the readout.
4-20 mA & % Conversions
Let the full range of Differential
Pressure Transmitter is 600mmWC
While applying pressure of say
400mmWC through pressure source ,
it is showing 398mmWC in hand held
communicator. What will be the 4-
20mA analog output from
Transmitter.
mA =
398 ×16
600
+ 4
= 14.61
% CONVERSION
% =
𝒎𝑨 −𝟒
𝟏𝟔
x 100 , i.e. = 66.33%

16. To know the smartness of a SMART instrument , let us consider the following
example –
Let’s say a process requires a minimum flow rate of 30m3/hr. If an operator uses old
analogue flow meter, he/she might set the flow to (+/-) 30 m3/hr without trusting
the accuracy of flow meter, just to be on safe side , the excess flow adds both the
raw material and disposal cost and the decreased flow leads to lower production
failing the set target.
But the rugged SMART flow meter replacing the older analog type automatically
detect its set value and accordingly maintain the flow leading to high accuracy and
efficiency.
The use of embedded technology in a single device which convert the non-electrical
output to some electrical output by mean of (4-20mAdc , 0-20mAdc) output
proportional to the real sensed process value are highly appreciable and much cost
effective.
The parallel development of control system with central processing and I/O
introduced more effective means to capture the information produced by these 4-
20mA instruments , scale the information to engineering units and store the record.
Example of Smartness

17. Thank You