1.Includes the relationship between the Open Loop, Close Loop and Safety Loop. 2.Includes the Flow and Temperature Instrumentation.

1. INSTRUMENTATION
Abhijeet Nagle.
Process Engineering
MITSKILLS

2. Functions & Modes:
Function:
Measurement
Control
Safety
Modes :
Open Loop
Close Loop
Safety Loop
Instrumentation provides accuracy & Consistency

3. Measuring
Point
Sensor
*
Transmitter
*
Indicator /
Recorder
**
Alarms /
Feedback's
**
Controller
**
Safety
Interlocks
**
Convertor
*
Controlling
Element
*
Controlling
Point
Switching
*
Process Control Block Diagram:
Close Loop
Safety Loop
Open Loop
Field Instruments:* Control System:**

4. Field Instrumentation:
Local Mechanical Type
Pneumatic Type
Electronic Type
Control Systems Instrumentation:
Control Panel

5. Measuring Instruments
Temperature
Flow

6. Temperature Measurement:
RTD
Thermo Couple (T/C)
RTD: (Ohms Law)
 V∝R
 Normally used material: Pt-100
 Range 0℃ to 650℃
2 Wire RTD 3 Wire RTD

7. Thermocouple: (Seeback effect)
 Range 0℃ to 2300℃
 Used material: platinum
Seeback Effect
Thermowell
(MOC: SS316)
Bar-stock Material
Tapered tube
Insertion
Length

8.  Flow Instruments:
 Differential Pressure Based Flow Instrument
 Variable Area Flow Meter/ Rotameter
 Magnetic Flow Meter
 Mass Flow Meter
 Ultrasonic Flow Meter
Differential Pressure Based Flow Instrument: (orifice)
 Sandwiched in flanges.
 Q∝ ∆𝑝
P1
P2
P3

9.  Variable Area Flow Meter: (Up thrust Pressure)
 Glass Tube Type
 Metal Tube Type
 Magnetic Flow Meter: ( Faraday’s Law)
 Applicable in Conductive fluid
(slurry & corrosive )
EMF ═ Fluid Flow
 Mass Flow Meters: (Accurate)
 Coriolisis Tubes (Ω, U, Straight Type)
 Ultrasonic Flow Meters:
 Non-contact type flow meter
 Used for high viscous & corrosive fluids
on very high pipeline size

10. Dilemma Between Luxury and Necessity while
selection of Instrument…

11. THANK YOU