8/6/2019 Technical Standards for Transmitters
1/43
Presentation onPresentation on
Technical Standards for TransmittersTechnical Standards for Transmitters
By : AJIT N. AHUJA
8/6/2019 Technical Standards for Transmitters
2/43
Technical Standards for TransmittersTechnical Standards for Transmitters
DefinitionDefinition : It is a device which :: It is a device which :
Converts a Process Variable into a standard signal ofConverts a Process Variable into a standard signal of
Analog (4Analog (4--20 mA) and Digital superimposed on 420 mA) and Digital superimposed on 4--2020mA ( for host complying HART protocol ) and transmitsmA ( for host complying HART protocol ) and transmitsit to a remote location.it to a remote location.
Process
Variable
Measurement
Remote Location
8/6/2019 Technical Standards for Transmitters
3/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Process Variables:Process Variables: The variables which are toThe variables which are to
be monitored & controlled in a process industrybe monitored & controlled in a process industry
primarily include:primarily include:
PressurePressure
FlowFlow
LevelLevel
TemperatureTemperature
8/6/2019 Technical Standards for Transmitters
4/43
Technical Standards for TransmittersTechnical Standards for Transmitters
OBJECTIVE ToUnderstand :
The need for Transmitters & Principles of Operation
The General Requirements for Transmitters
Specific Requirements for Pres.& Diff Pres Transmitters (SECL/EIL)
Transmitter Accessories
SelectionC
riterion for Pressure Transmitters Salient features of Emerson 3051S Series Transmitters
General considerations for Handling & Transportation
of Transmitters
8/6/2019 Technical Standards for Transmitters
5/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Why do weneed Transmitters ?
As an integral part ofCentralized Process Monitoring &
Control :
Optimized Process Performance
Aids in Generation of MIS Reports
8/6/2019 Technical Standards for Transmitters
6/43
Technical Standards for TransmittersTechnical Standards for Transmitters
PRINCIPLES OFOPERATION
Measurement of Pressure
Measurement of Flow Measurement of Level
BASIC PROCESS
VARIABLE FOR
8/6/2019 Technical Standards for Transmitters
7/43
Technical Standards for TransmittersTechnical Standards for Transmitters
PRINCIPLES OFOPERATION
Pressure measurement techniques widely employed are :
Capacitance Type
Strain Gauge Type
Piezoelectric Type
Differential Transformer Type
8/6/2019 Technical Standards for Transmitters
8/43
Technical Standards for TransmittersTechnical Standards for Transmitters
PRINCIPLES OFOPERATIONCAPACITANCE TYPE :
8/6/2019 Technical Standards for Transmitters
9/43
Technical Standards for TransmittersTechnical Standards for Transmitters
PRINCIPLES OFOPERATIONCAPACITANCE TYPE
8/6/2019 Technical Standards for Transmitters
10/43
Technical Standards for TransmittersTechnical Standards for Transmitters
PRINCIPLES OFOPERATION STRAIN GAUGE TYPE :
The metallic strain gauge consists of a very fine wire or,
more commonly, metallic foil arranged in a grid pattern.
The grid pattern maximizes the amount of metallic wireor foil subject to strain in the parallel direction. The grid is
bonded to a thin backing, called the carrier, which is
attached directly to the test specimen. Therefore, the
strain experienced by the test specimen is transferred
directly to the strain gauge, which responds with a linear
change in electrical resistance. Strain gauges are
available commercially with nominal resistance values
from 30 to 3000 , with 120, 350, and 1000 being the
most common value
8/6/2019 Technical Standards for Transmitters
11/43
Technical Standards for TransmittersTechnical Standards for Transmitters
PRINCIPLES OFOPERATION STRAIN GAUGE TYPE :
8/6/2019 Technical Standards for Transmitters
12/43
Technical Standards for TransmittersTechnical Standards for Transmitters
PRINCIPLES OFOPERATION STRAIN GAUGE TYPE :
8/6/2019 Technical Standards for Transmitters
13/43
Technical Standards for TransmittersTechnical Standards for Transmitters
PRINCIPLES OFOPERATION
Piezoelectricity is an Electric Voltage produced by
certainc
rystals and by a numbe
rofce
ramicmate
rialswhenthey aresubjectedto pressure .
This property can beuseful inmeasurementofStatic
pressure.
PIEZOELECTRIC TYPE:
8/6/2019 Technical Standards for Transmitters
14/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SiliconResonant SensorTechnologySiliconResonant SensorTechnology
Silicon resonant sensors are fabricated from a singleSilicon resonant sensors are fabricated from a single
crystal silicon. As pressure is applied, the bridges arecrystal silicon. As pressure is applied, the bridges aresimultaneously stressed, one in compression and one insimultaneously stressed, one in compression and one intension. The resulting change in resonant frequencytension. The resulting change in resonant frequencyproduces a high differential output (kHz) directlyproduces a high differential output (kHz) directlyproportional to the applied pressure. This simple timeproportional to the applied pressure. This simple time--
based function is managed by a microprocessor.based function is managed by a microprocessor.MicroMicro--machined from a single silicone crystal to providemachined from a single silicone crystal to provide
superior stability and repeatability while eliminatingsuperior stability and repeatability while eliminating
hysteresis.hysteresis.
PRINCIPLES OFOPERATION PIEZOELECTRIC TYPE:
8/6/2019 Technical Standards for Transmitters
15/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Temperature effects are less than 1/10th of other siliconTemperature effects are less than 1/10th of other silicon
technologies (10 ppm/deg C), making this extremelytechnologies (10 ppm/deg C), making this extremelystable in the most demanding process applications. Thestable in the most demanding process applications. The
output produces a much higher signal to noise ratio asoutput produces a much higher signal to noise ratio as
compared to analog sensors. Errors resulting fromcompared to analog sensors. Errors resulting from
temperature and static pressure are insignificant intemperature and static pressure are insignificant in
relation to total output.relation to total output.
This advanced sensor technology is applied toThis advanced sensor technology is applied to
Yokogawa's DPharp EJX seriesYokogawa's DPharp EJX series pressurepressure transmitter.transmitter.
PRINCIPLES OFOPERATION PIEZOELECTRIC TYPE:
8/6/2019 Technical Standards for Transmitters
16/43
Technical Standards for TransmittersTechnical Standards for Transmitters
General requirementsforTransmitters ?
Operating Voltage : 24 DC / 110 V 50 Hz AC
Two Wire System with 4-20 mA Standard Output with
. superimposed digital signal having simultaneous
. analog & digital communication , using HART Protocol.
LCD Display in Engineering Units and % for level in field
Mounting : 2pipe Mounted or Panel Mounted Intrinsically Safe or Ex-proof
Microprocessor based with non-volatile memory
8/6/2019 Technical Standards for Transmitters
17/43
Technical Standards for TransmittersTechnical Standards for Transmitters
General requirementsforTransmitters ?
Range : Process variable is indicated within
40 to 60% for linear , 60 to 80% for square root inputs
Accuracy : +/- 0.1% of span for a rangeability of 1:100
External zero adjustment and Integral vent / drain
Tx to run complete Auto Diagnostic Routine, in event of
failure, o/p shall be driven to predefined value.
Response Time
8/6/2019 Technical Standards for Transmitters
18/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Specific requirements for Pressure / DP Transmitters
Pressure :
Atmospheric Pressure : Pressure on the surface of earth
due to column of air above
Gauge Pressure : Pressure above Atm. Pressure
(excluding Atm. Pressure)
Absolute Pressure : Gauge pressure + Atm. Pressure
Differential Pressure : Pressure difference across a
restriction in fluid flow path in pipe
or in a liquid column in a vessel
8/6/2019 Technical Standards for Transmitters
19/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Specific requirements for Pressure / DP Transmitters
Differential & Absolute PTs shall be :
316 SS Capsule Diaphragm
CS Bodies or SS 316 or Monel or Tantalum
NPT Threaded Process Connections / Flange
Connection 1/2/3 depending on the service.
DPT with Integral Manifold
8/6/2019 Technical Standards for Transmitters
20/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Specific requirements for Pressure / DP Transmitters
Over Range protection :
PTs : able to withstand ORP ~ 100% of max. span
DPTs: able to withstand ORP ~ body rating on either
side of the element
RFI Interference / Magnetic Interference:
+/- 0.1% of span from 20 to 1000 MHz and for field
strength upto 30 V/m.
8/6/2019 Technical Standards for Transmitters
21/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Transmitter Accessories
Volumetric Diaphragm Seals
Capillary Tubes
Manifolds : Coplanar Design , Traditional Design ,
Inline Design
8/6/2019 Technical Standards for Transmitters
22/43
Technical Standards for TransmittersTechnical Standards for Transmitters
ACCESSORIES
8/6/2019 Technical Standards for Transmitters
23/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SELECTION CRITERION
Functional Specifications
Performance Specifications
Material Selection
Desirable Features
8/6/2019 Technical Standards for Transmitters
24/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SELECTION CRITERION
FUNCTIONAL SPECIFICATIONS
Temperature : Maximum Process & Ambient Temp.
Pressure : Operating Pressure Range & Maximum Press.;
Minimum Pressure (vacuum) ; Static line
pressure for differential transmitters,
Environment : The transmitter should be capable ofoperating in environments with 0 to 100%
relative humidity. The working fluid and the
ambient environment should be considered
for corrosiveness.
8/6/2019 Technical Standards for Transmitters
25/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SELECTION CRITERION
DefinitionofHazardousLocations:
Class I, Division I
Locations in which hazardous concentrations of flammable gases or
vapors exist continuously, intermittently, or periodically under normaloperating conditions.
Class I, Division II
Locations in which volatile flammable gases are handled, processed
or used, but in which the hazardous liquids, vapors or gases will
normally
be confined within closed containers or closed systems from which
they can escape only in case of accidental rupture or breakdown of
such systems or containers, or in case of abnormal operation of
Equipment.
8/6/2019 Technical Standards for Transmitters
26/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SELECTION CRITERION
Class II Locations
Locations which are hazardous because of the presence of combustible
dust.
Class III Locations
Locations in which easily ignitable fibers or materials producing
combustible flyings are present.
Group A
Atmospheres containing acetylene.
Group B
Atmospheres containing hydrogen or gases or vapors of equivalent
hazards such as manufactured gas.
8/6/2019 Technical Standards for Transmitters
27/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SELECTION CRITERION
Group C
Atmospheres containing ethyl ether vapors, ethylene, or cyclopropane.
Group D
Atmospheres containing gasoline, hexane, naptha,benzine, butane,
alcohol, benzol, lacquer solvent vapors, or natural gases.
Group E
Atmospheres containing metal dust, including aluminum, magnesium,
and their commercial alloys, and other metals of similarly hazardouscharacteristics.
Group F
Atmospheres containing carbon black coal or coke dust.
8/6/2019 Technical Standards for Transmitters
28/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SELECTION CRITERION
Group G
Atmospheres containing flour, starch, or grain dusts.
Explosion-ProofEnclosureExplosion-proof enclosure means an enclosure for electrical
apparatus which is capable of withstanding, without damage, an
explosion which may occur within it, of a specified gas or vapor,
and capable of preventing ignition of a specified gas or vapor
surrounding the enclosure from sparks or flames from theexplosion of the specified gas or vapor within the enclosure. To
make a system explosion-proof, the enclosure must be capable ofwithstanding an explosion.
8/6/2019 Technical Standards for Transmitters
29/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SEL
ECTIO
N CR
ITER
IO
NIntrinsically Safe EquipmentIntrinsically safe equipment and wiring are incapable of releasing
sufficient electrical energy under normal or abnormal conditions to cause
ignition of a specific hazardous atmospheric mixture. Abnormal conditions
will include accidental damage to any part of the equipment or wiring,
insulation, or other failure of electrical components, application of overvoltage, adjustment and maintenance operations, and other similar
conditions. Equipment built for this requirement is designed with low
energy storage components.
Several advantages to the intrinsic safety approach are listed below.These advantages have to be weighed against the initial higher purchase
price :
Lower installation cost Less operator-dependent to maintain a safe
system Easier to maintain and repair Accessible to repair without
special precautions before opening the unit
8/6/2019 Technical Standards for Transmitters
30/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SEL
ECTIO
N CR
ITER
IO
NPERFORMANCE SPECIFICATIONSACCURACY : Closeness to the actual value .
HYSTERISIS : Hysteresis is the maximum difference for
the same input between the upscale and
downscale output values during a full range
traverse in each direction.
REPEATIBILITY : Repeatability is the closeness of
agreement among a number of
consecutive measurements of the output
for the same value of the input under the
same operating conditions, approaching
from the same direction. It does not
include hysteresis
8/6/2019 Technical Standards for Transmitters
31/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SEL
ECTIO
N CR
ITER
IO
NPERFORMANCE SPECIFICATIONS
Reproducibility : Reproducibility is the closeness of
agreement among repeated measurements of the
output for the same value of input mode under thesame operating Conditions over a period of time,
approaching from both directions. Normally this
implies a long period of time. It includes hysteresis,
drift, and repeatability.
8/6/2019 Technical Standards for Transmitters
32/43
Technical Standards for TransmittersTechnical Standards for TransmittersSELECTION CRITERION
8/6/2019 Technical Standards for Transmitters
33/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SEL
ECTIO
N CR
ITER
IO
N
8/6/2019 Technical Standards for Transmitters
34/43
Technical Standards for TransmittersTechnical Standards for Transmitters
SEL
ECTIO
N CR
ITER
IO
NFEATURES :
Range Adjustability
External Zero Adjustment
Adjustable Damping for pulsating process conditions
Reverse Polarity Protection
Installation Considerations for greater Flexibility
Local Indications may be considered eg. for tank level
Modular Plug in Circuit Boards for easily accessible test
pts.
8/6/2019 Technical Standards for Transmitters
35/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Salient Features of Emerson Series 3051 S Transmitters
Power Supply Variation: 10.5 to 42.4 V DC with no load
Model No.: 3051S1CD 2 A 2 E12 A 1A B4
Diaphragm Material :
Hastelloy
Monel
Tantalum
Gold Plated Monel
Gold Plated 316L SST
8/6/2019 Technical Standards for Transmitters
36/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Salient Features of Emerson Series 3051 S Transmitters
Transmitter Labels :
Information Label:
Name & Address of Manufacturer
Complete Model No.
Device Serial No.
Year ofConstruction
Marking for Explosion Protection
8/6/2019 Technical Standards for Transmitters
37/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Salient Features of Emerson Series 3051 S Transmitters
Transmitter Labels :
Intrinsic Safety Housing Label
Type n Housing Label Dust Housing Label
Flame Proof Label
8/6/2019 Technical Standards for Transmitters
38/43
Technical Standards for TransmittersTechnical Standards for Transmitters
Salient Features of Emerson Series 3051 S Transmitters
8/6/2019 Technical Standards for Transmitters
39/43
Technical Standards for TransmittersTechnical Standards for TransmittersSalient Features of Emerson Series 3051 S Transmitters
8/6/2019 Technical Standards for Transmitters
40/43
Technical Standards for TransmittersTechnical Standards for Transmitters
General Packaging & Handling Procedures for Transmitters :
A Permanent Tag to be attached on each Tx specifying:
Tag No,
Manufacturers Name or Trademark, Model No. or Type,
Serial No.,
Press-Temp rating,
Body & Material Element, Calibrated Span & Units,
Range Limits
Power Supply-Electrical Classification
8/6/2019 Technical Standards for Transmitters
41/43
Technical Standards for TransmittersTechnical Standards for Transmitters
General Packaging & Handling Procedures for Transmitters :
Each Carton or Box to be marked with the Instrument
Tag No. on top & side of the Carton
For Larger Box containing multiple cartons the larger
box to be marked on top with all Tag Nos.
All ports & openings to be sealed, threaded connections
protected using caps or plugs.
8/6/2019 Technical Standards for Transmitters
42/43
Technical Standards for TransmittersTechnical Standards for Transmitters
CONCLUSION
Provides guidelines for the Key Technical Specifications to
be followed while selecting & ordering Transmitters.
&
DISCUSSION
8/6/2019 Technical Standards for Transmitters
43/43
Thank You !!Thank You !!