DOE FUNDAMENTALS HANDBOOK INSTRUMENTATION AND CONTROL
The Instrumentation and Control Fundamentals Handbook was developed to assist nuclear
facility operating contractors provide operators, maintenance personnel, and the technical staff with
the necessary fundamentals training to ensure a basic understanding of instrumentation and control
systems. The handbook includes information on temperature, pressure, flow, and level detection
systems; position indication systems; process control systems; and radiation detection principles.
This information will provide personnel with an understanding of the basic operation of various
types of DOE nuclear facility instrumentation and control systems.......
DOE-HDBK-1013/1-92
JUNE 1992
DOE FUNDAMENTALS HANDBOOK
INSTRUMENTATION AND CONTROL
Volume 1 of 2
U.S. Department of Energy FSC-6910
Washington, D.C. 20585
Distribution Statement A. Approved for public release; distribution is unlimited.
This document has been reproduced directly from the best available copy.
Available to DOE and DOE contractors from the Office of Scientific and Technical Information.
P. O. Box 62, Oak Ridge, TN 37831; (615) 576-8401.
Available to the public from the National Technical Information Service, U.S. Department of
Commerce, 5285 Port Royal Rd., Springfield, VA 22161.
Order No. DE92019792
INSTRUMENTATION AND CONTROL
ABSTRACT
The Instrumentation and Control Fundamentals Handbook was developed to assist nuclear
facility operating contractors provide operators, maintenance personnel, and the technical staff with
the necessary fundamentals training to ensure a basic understanding of instrumentation and control
systems. The handbook includes information on temperature, pressure, flow, and level detection
systems; position indication systems; process control systems; and radiation detection principles.
This information will provide personnel with an understanding of the basic operation of various
types of DOE nuclear facility instrumentation and control systems.
Key Words: Training Material, Temperature Detection, Pressure Detection, Level Detection,
Flow Detection, Position Indication, Radiation Detection, Process Control
Rev. 0 IC
INSTRUMENTATION AND CONTROL
FOREWORD
The Department of Energy (DOE) Fundamentals Handbooks consist of ten academic
subjects, which include Mathematics; Classical Physics; Thermodynamics, Heat Transfer, and
Fluid Flow; Instrumentation and Control; Electrical Science; Material Science; Mechanical
Science; Chemistry; Engineering Symbology, Prints, and Drawings; and Nuclear Physics and
Reactor Theory. The handbooks are provided as an aid to DOE nuclear facility contractors.
These handbooks were first published as Reactor Operator Fundamentals Manuals in 1985
for use by DOE Category A reactors. The subject areas, subject matter content, and level of
detail of the Reactor Operator Fundamentals Manuals was determined from several sources.
DOE Category A reactor training managers determined which materials should be included, and
served as a primary reference in the initial development phase. Training guidelines from the
commercial nuclear power industry, results of job and task analyses, and independent input from
contractors and operations-oriented personnel were all considered and included to some degree
in developing the text material and learning objectives.
The DOE Fundamentals Handbooks represent the needs of various DOE nuclear facilities'
fundamentals training requirements. To increase their applicability to nonreactor nuclear facilities,
the Reactor Operator Fundamentals Manual learning objectives were distributed to the Nuclear
Facility Training Coordination Program Steering Committee for review and comment. To update
their reactor-specific content, DOE Category A reactor training managers also reviewed and
commented on the content. On the basis of feedback from these sources, information that applied
to two or more DOE nuclear facilities was considered generic and was included. The final draft
of each of these handbooks was then reviewed by these two groups. This approach has resulted
in revised modular handbooks that contain sufficient detail such that each facility may adjust the
content to fit their specific needs.
Each handbook contains an abstract, a foreword, an overview, learning objectives, and
text material, and is divided into modules so that content and order may be modified by individual
DOE contractors to suit their specific training needs. Each subject area is supported by a separate
examination bank with an answer key.
The DOE Fundamentals Handbooks have been prepared for the Assistant Secretary for
Nuclear Energy, Office of Nuclear Safety Policy and Standards, by the DOE Training
Coordination Program. This program is managed by EG&G Idaho, Inc.
Rev. 0 IC
INSTRUMENTATION AND CONTROL
OVERVIEW
The Department of Energy Fundamentals Handbook entitled Instrumentation and Control
was prepared as an information resource for personnel who are responsible for the operation of
the Department's nuclear facilities. A basic understanding of instrumentation and control is
necessary for DOE nuclear facility operators, maintenance personnel, and the technical staff to
safely operate and maintain the facility and facility support systems. The information in the
handbook is presented to provide a foundation for applying engineering concepts to the job. This
knowledge will help personnel more fully understand the impact that their actions may have on the
safe and reliable operation of facility components and systems.
The Instrumentation and Control handbook consists of seven modules that are contained
in two volumes. The following is a brief description of the information presented in each module
of the handbook.
Volume 1 of 2
Module 1 - Temperature Detectors
This module describes the construction, operation, and failure modes for various
types of temperature detectors and indication circuits.
Module 2 - Pressure Detectors
This module describes the construction, operation, and failure modes for various
types of pressure detectors and indication circuits.
Module 3 - Level Detectors
This module describes the construction, operation, and failure modes for various
types of level detectors and indication circuits.
Module 4 - Flow Detectors
This module describes the construction, operation, and failure modes for various
types of flow detectors and indication circuits.
Module 5 - Position Indicators
This module describes the construction, operation, and failure modes for various
types of position indicators and control circuits.
Rev. 0 IC
INSTRUMENTATION AND CONTROL
Volume 2 of 2
Module 6 - Radiation Detectors
This module describes the principles of radiation detection, detector operation,
circuit operation, and specific radiation detector applications.
Module 7 - Principles of Control Systems
This module describes the principles of operation for control systems used in
evaluating and regulating changing conditions in a process.
The information contained in this handbook is by no means all encompassing. An attempt
to present the entire subject of instrumentation and control would be impractical. However, the
Instrumentation and Control handbook does present enough information to provide the reader
with a fundamental knowledge level sufficient to understand the advanced theoretical concepts
presented in other subject areas, and to better understand basic system and equipment operations.
Rev. 0 IC
Department of Energy
Fundamentals Handbook
INSTRUMENTATION AND CONTROL
Module 1
Temperature Detectors
Temperature Detectors TABLE OF CONTENTS
TABLE OF CONTENTS
LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
OBJECTIVES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
RESISTANCE TEMPERATURE DETECTORS (RTDs) . . . . . . . . . . . . . . . . . . . . . . . . 1
Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
RTD Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
THERMOCOUPLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Thermocouple Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Thermocouple Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
FUNCTIONAL USES OF TEMPERATURE DETECTORS . . . . . . . . . . . . . . . . . . . . . . 8
Functions of Temperature Detectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Detector Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Environmental Concerns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
TEMPERATURE DETECTION CIRCUITRY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Bridge Circuit Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Bridge Circuit Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Temperature Detection Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Temperature Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Rev. 0 Page i IC-01
LIST OF FIGURES Temperature Detectors
LIST OF FIGURES
Figure 1 Electrical Resistance-Temperature Curves . . . . . . . . . . . . . . . . . . . . . . . . . 2
Figure 2 Internal Construction of a Typical RTD . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Figure 3 RTD Protective Well and Terminal Head . . . . . . . . . . . . . . . . . . . . . . . . . 4
Figure 4 Thermocouple Material Characteristics
When Used with Platinum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Figure 5 Internal Construction of a Typical Thermocouple . . . . . . . . . . . . . . . . . . . 6
Figure 6 Simple Thermocouple Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 7 Temperature-vs-Voltage Reference Table . . . . . . . . . . . . . . . . . . . . . . . . . 7
Figure 8 Bridge Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 9 Unbalanced Bridge Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 10 Balanced Bridge Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 11 Block Diagram of a Typical Temperature
Detection Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 12 Resistance Thermometer Circuit with Precision
Resistor in Place of Resistance Bulb . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
IC-01 Page ii Rev. 0
Temperature Detectors LIST OF TABLES
LIST OF TABLES
NONE
Rev. 0 Page iii IC-01
REFERENCES Temperature Detectors
REFERENCES
Kirk, Franklin W. and Rimboi, Nicholas R., Instrumentation, Third Edition, American
Technical Publishers, ISBN 0-8269-3422-6.
Academic Program for Nuclear Power Plant Personnel, Volume IV, General Physics
Corporation, Library of Congress Card #A 397747, April 1982.
Fozard, B., Instrumentation and Control of Nuclear Reactors, ILIFFE Books Ltd., London.
Wightman, E.J., Instrumentation in Process Control, CRC Press, Cleveland, Ohio.
Rhodes, T.J. and Carroll, G.C., Industrial Instruments for Measurement and Control,
Second Edition, McGraw-Hill Book Company.
Process Measurement Fundamentals, Volume I, General Physics Corporation, ISBN 0-
87683-001-7, 1981.
IC-01 Page iv Rev. 0
Temperature Detectors OBJECTIVES
TERMINAL OBJECTIVE
1.0 Given a temperature instrument, RELATE the associated fundamental principles,
including possible failure modes, to that instrument.
ENABLING OBJECTIVES
1.1 DESCRIBE the construction of a basic RTD including:
a. Major component arrangement
b. Materials used
1.2 EXPLAIN how RTD resistance varies for the following:
a. An increase in temperature
b. A decrease in temperature
1.3 EXPLAIN how an RTD provides an output representative of the measured
temperature.
1.4 DESCRIBE the basic construction of a thermocouple including:
a. Major component arrangement
b. Materials used
1.5 EXPLAIN how a thermocouple provides an output representative of the measured
temperature.
1.6 STATE the three basic functions of temperature detectors.
1.7 DESCRIBE the two alternate methods of determining temperature when the normal
temperature sensing devices are inoperable.
1.8 STATE the two environmental concerns which can affect the accuracy and reliability of
temperature detection instrumentation.
1.9 Given a simplified schematic diagram of a basic bridge circuit, STATE the purpose of
the following components:
a. R1 and R2
b. Rx
c. Adjustable resistor
d. Sensitive ammeter
Rev. 0 Page v IC-01
OBJECTIVES Temperature Detectors
ENABLING OBJECTIVES (Cont.)
1.10 DESCRIBE the bridge circuit conditions that create a balanced bridge.
1.11 Given a block diagram of a basic temperature instrument detection and control system,
STATE the purpose of the following blocks:
a. RTD
b. Bridge circuit
c. DC-AC converter
d. Amplifier
e. Balancing motor/mechanical linkage
1.12 DESCRIBE the temperature instrument indication(s) for the following circuit
faults:
a. Short circuit
b. Open circuit
1.13 EXPLAIN the three methods of bridge circuit compensation for changes in
ambient temperature.
IC-01 Page vi Rev. 0
Temperature Detectors RESISTANCE TEMPERATURE DETECTORS (RTDs)
RESISTANCE TEMPERATURE DETECTORS (RTDs)
The resistance of certain metals will change as temperature changes. This
characteristic is the basis for the operation of an RTD.
EO 1.1 DESCRIBE the construction of a basic RTD including:
a. Major component arrangement
b. Materials used
EO 1.2 EXPLAIN how RTD resistance varies for the following:
a. An increase in temperature
b. A decrease in temperature
EO 1.3 EXPLAIN how an RTD provides an output
representative of the measured temperature.
Temperature
The hotness or coldness of a piece of plastic, wood, metal, or other material depends upon the
molecular activity of the material. Kinetic energy is a measure of the activity of the atoms which
make up the molecules of any material. Therefore, temperature is a measure of the kinetic
energy of the material in question.
Whether you want to know the temperature of the surrounding air, the water cooling a car’s
engine, or the components of a nuclear facility, you must have some means to measure the
kinetic energy of the material. Most temperature measuring devices use the energy of the
material or system they are monitoring to raise (or lower) the kinetic energy of the device. A
normal household thermometer is one example. The mercury, or other liquid, in the bulb of the
thermometer expands as its kinetic energy is raised. By observing how far the liquid rises in the
tube, you can tell the temperature of the measured object.
Because temperature is one of the most important parameters of a material, many instruments
have been developed to measure it. One type of detector used is the resistance temperature
detector (RTD). The RTD is used at many DOE nuclear facilities to measure temperatures of
the process or materials being monitored.
Rev. 0 Page 1 IC-01
RESISTANCE TEMPERATURE DETECTORS (RTDs) Temperature Detectors
RTD Construction
The RTD incorporates pure metals
or certain alloys that increase in
resistance as temperature increases
and, conversely, decrease in
resistance as temperature
decreases. RTDs act somewhat
like an electrical transducer,
converting changes in temperature
to voltage signals by the
measurement of resistance. The
metals that are best suited for use
as RTD sensors are pure, of
uniform quality, stable within a
given range of temperature, and
able to give reproducible
resistance-temperature readings.
Only a few metals have the
Figure 1 Electrical Resistance-Temperature Curves
properties necessary for use in
RTD elements.
RTD elements are normally constructed of platinum, copper, or nickel. These metals are best
suited for RTD applications because of their linear resistance-temperature characteristics (as
shown in Figure 1), their high coefficient of resistance, and their ability to withstand repeated
temperature cycles.
The coefficient of resistance is the change in resistance per degree change in temperature, usually
expressed as a percentage per degree of temperature. The material used must be capable of being
drawn into fine wire so that the element can be easily constructed.
IC-01 Page 2 Rev. 0
