This presentation discusses various types of industrial transmitters used to transmit sensor signals. It describes sensors that detect process variables and transducers that convert these detections to signals transmitters can understand. Common transmitter types are then outlined, including pressure, temperature, flow, and level transmitters. Pressure transmitters measure gases and liquids using different pressure readings. Temperature transmitters interface temperature sensors to control systems using standard current signals. Flow transmitters quantify liquid and gas flow rates using differential pressure, electromagnetic induction, or ultrasound. Level transmitters determine heights using capacitance, pressure, radar, or ultrasound based on the application.

1. INDUSTRIAL TRANSMITTERS
PRESENTED TO:
ENGINEERING DEPT. SEPL.
PRESENTED BY:
MUHAMMAD FAIZAN SALEEM
Presentation # 3
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2. CONTENTS
 Sensor
 Transducer
 Transmitter
 Types of transmitter
 Applications of Transmitters
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3. SENSOR
 A sensor is an object whose purpose is to detect
events or changes in its environment, and then
provide a corresponding output.
 Primary element.
 Examples: Human body, Hall effect sensor etc.
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4. TRANSDUCER
 A transducer is a device that receives a signal and
converts it in a different form(Readable for devices).
For example, I/P transducers that convert a current
signal to pneumatic form.
 Also thermocouple represents a temperature
change as a voltage change.
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5. TRANSDUCER TYPES
 Active Transducer(e.g. TC , Piezoelectric
accelerometer)
• Do not require any input power for operation.
 Passive Transducer(e.g. LDR,RTD)
• Require input power for operation
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6. RTD VS. THERMOCOUPLE
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7. ADV. & DISADV. OF RTD AND TC
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8. TRANSMITTERS
 A set of equipment used to generate and transmit
electromagnetic waves carrying messages or
signals.
 A transmitter which we deals with usually converts the
sensor output to a signal level appropriate for input to a
controller, such as 4 to 20 mA.
 It is secondary element.
 Transmitters are generally designed to be direct acting.
 Mostly transmitters have an adjustable input range.
 For example, input range of a platinum resistance
element (the sensor) is 50 to 150 °C.
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9. TRANSMITTER TYPES
 Pressure Transmitter
 Temperature Transmitter
 Flow Transmitter
 Level Transmitter
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10. PRESSURE TRANSMITTER
 A pressure transmitter is a device that measures
pressure in a liquid, fluid, or gas.
 It generates a signal as a function of
the pressure imposed.
 There are three kinds of pressure transmitters.
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11. TYPES
i. Absolute Pressure Transmitters
• Pressure measured relative to perfect vacuum.
ii. Differential Pressure Transmitters
• Pressures of two distinct positions are compared.
iii. Gauge Pressure Transmitters
• Subtype of differential pressure measurement where
we compare pressure at any point to the current
atmospheric pressure
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13. PRESSURE TRANSMITTER WIRE
CONFIGURATION
 Two Wire Transmitter(loop powered instruments)
 In two wire system, the only source of power to
transmitter is from the single loop.
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14. CONTINUE..
 Three wire transmitter
 Some instruments require more power than single loop.
DC common wire is run from the instrument to the
transmitter.
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15. CONTINUE..
 Four Wire Transmitter(self-powered instruments)
 They require no connection to DC power supply.
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16. APPLICATIONS
 Touch Screen Devices
 Automotive Industry
 Aviation
 Marine Industry
 Industrial Uses
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17. TEMPERATURE TRANSMITTER
 A temperature transmitter is an electrical instrument
that interfaces a temperature sensor (e.g.
thermocouple, RTD, or thermistor) to a
measurement or control device (e.g. PLC, DCS, PC
etc.).
 It is used to convert a temperature sensor’s low-
level (ohm or mV) signal to a standard 4-20mA
current signal that can be readily accepted by a
monitoring and control system, such as a DCS or
PLC.
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18. WORKING PRINCIPLE
 Two wire transmitter accepts input from a
thermocouple or three wire pt100 and converts the
output into 4-20mA current signal.
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19. USES OF TEMPERATURE TRANSMITTER
 The signals generated by Resistance Temperature
Detector or Thermocouple are categorized as low-
level signal hence it has more noise immunity.
 No need to provide special I/O card for
thermocouple/RTD. Just connect the Transmitter to
the Analog I/O card.
 Provided maintenance facilities such as diagnostic
feature in smart transmitter.
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20. FLOW TRANSMITTER
 Flow transmitters are an integral tool for measuring
the flow of liquid, gas, or a mixture of both.
 There are following types of flow transmitters:
 Differential-pressure flow meter
 Electromagnetic flow meter (magmeter)
 Ultrasonic flow meter
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21. DIFFERENTIAL-PRESSURE FLOW METER
 It measures the differential-pressure drop across a
constriction in the flow’s path to get the flow
velocity.
 Measuring this differential pressure gives a direct
measure of the flow velocity from which the
volumetric flow can easily be calculated.
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22. ELECTROMAGNETIC FLOW METER
(MAGMETER)
 It is based on Faraday’s Law of electromagnetism.
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23. ULTRASONIC FLOW METER
 Doppler-shift meter(Can not measure extremely
clean liquids)
 Transit-time meter
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24. APPLICATIONS
 Food and beverage industry.
 Oil and gas plants.
 Chemical/pharmaceutical factories
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25. LEVEL TRANSMITTERS
 A Level Transmitter is simply an instrument that
provides continuous level measurement.
 Level transmitters transmit a particular output signal
that is ideally compatible with a corresponding
sensor and meter/indicator in a given application.
Common outputs include:
 Current loops
 Fieldbus protocols
 Frequency signals
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26. TYPES OF LEVEL TRANSMITTER
 Capacitance
 Pressure
 Radar
 Ultrasonic
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27. CAPACITANCE LEVEL TRANSMITTER
 In this transmitter capacitance of capacitor is
changed w.r.t. level.
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28. PRESSURE LEVEL TRANSMITTER
 Pressure sensor is placed at the bottom and gives
output with respect to the pressure applied.
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29. RADAR LEVEL TRANSMITTER
 Emits high frequency radar pulses from the antenna
and reflected from the product surface.
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30. ULTRASONIC LEVEL TRANSMITTER
 Measures time between emission and reflection of
acoustic signals to determine level.
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