1、NEMA Standards PublicationNational Electrical Manufacturers AssociationNEMA DC 3-2013Residential ControlsElectrical Wall-Mounted Room ThermostatsNEMA DC 3-2013 Residential ControlsElectrical Wall-Mounted Room Thermostats Published by National Electrical Manufacturers Association 1300 North 17th Stre
2、et, Suite 900 Rosslyn, Virginia 22209 www.nema.org Copyright 2014 by the National Electrical Manufacturers Association. All rights including translation into other languages, reserved under the Universal Copyright Convention, the Berne Convention for the Protection of Literary and Artistic Works, an
3、d the International and Pan American Copyright Conventions. NOTICE AND DISCLAIMER The information in this publication was considered technically sound by the consensus of persons engaged in the development and approval of the document at the time it was developed. Consensus does not necessarily mean
4、 that there is unanimous agreement among every person participating in the development of this document. The National Electrical Manufacturers Association (NEMA) standards and guideline publications, of which the document contained herein is one, are developed through a voluntary consensus standards
5、 development process. This process brings together volunteers and/or seeks out the views of persons who have an interest in the topic covered by this publication. While NEMA administers the process and establishes rules to promote fairness in the development of consensus, it does not write the docum
6、ent and it does not independently test, evaluate, or verify the accuracy or completeness of any information or the soundness of any judgments contained in its standards and guideline publications. NEMA disclaims liability for any personal injury, property, or other damages of any nature whatsoever,
7、whether special, indirect, consequential, or compensatory, directly or indirectly resulting from the publication, use of, application, or reliance on this document. NEMA disclaims and makes no guaranty or warranty, expressed or implied, as to the accuracy or completeness of any information published
8、 herein, and disclaims and makes no warranty that the information in this document will fulfill any of your particular purposes or needs. NEMA does not undertake to guarantee the performance of any individual manufacturer or sellers products or services by virtue of this standard or guide. In publis
9、hing and making this document available, NEMA is not undertaking to render professional or other services for or on behalf of any person or entity, nor is NEMA undertaking to perform any duty owed by any person or entity to someone else. Anyone using this document should rely on his or her own indep
10、endent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable care in any given circumstances. Information and other standards on the topic covered by this publication may be available from other sources, which the user may wish to consult
11、for additional views or information not covered by this publication. NEMA has no power, nor does it undertake to police or enforce compliance with the contents of this document. NEMA does not certify, test, or inspect products, designs, or installations for safety or health purposes. Any certificati
12、on or other statement of compliance with any health or safetyrelated information in this document shall not be attributable to NEMA and is solely the responsibility of the certifier or maker of the statement. DC 3-2013 Page i 2014 National Electrical Manufacturers Association CONTENTS Page Foreword
13、. iii History of Standards iv Section 1 GENERAL . 1 1.1 Scope 1 1.2 References 1 1.2.1 Normative References. 1 1.3 Definitions 1 Section 2 RATINGS AND CLASSIFICATION . 5 2.1 Electrical Ratings. 5 2.1.1 Low-Voltage Thermostats . 5 2.1.2 Line-Voltage Thermostats (AC) . 5 2.2 Functional Groups . 5 2.2.
14、1 Group 5 2.2.2 Sub-Group . 6 2.3 Auxiliary Components . 6 2.3.1 Functions . 6 2.3.2 Thermometers . 6 2.3.3 Function or Status Indicators . 6 Section 3 CONSTRUCTION . 7 3.1 Connections 7 3.1.1 Low-Voltage Thermostats . 7 3.1.2 Line-Voltage Thermostats . 7 3.2 Materials 7 3.2.1 Projections . 7 3.2.2
15、Parts Intended for Setting 7 3.2.3 Capable of Withstanding Conditions . 7 3.2.4 Iron and Steel Parts . 8 3.2.5 Enclosures for Low-Voltage Thermostats . 8 3.2.6 Enclosures for Line-Voltage Thermostats . 8 3.3 Assembly . 8 3.4 Adjustments and Settings . 8 3.4.1 Factory Adjustment . 8 3.4.2 Sealing and
16、 Locking 8 3.5 Line-Voltage Thermostat Grounding (Earthing) 8 Section 4 TESTING AND PERFORMANCE . 10 4.1 Dielectric Tests 10 4.1.1 Low-Voltage Thermostats . 10 4.1.2 Line-Voltage Thermostats . 10 4.2 Endurance . 10 4.2.1 Low-Voltage Thermostats . 10 4.2.2 Line-Voltage Thermostats . 10 4.3 Overload T
17、est (Line-Voltage Thermostats) . 10 4.4 Temperature (Line-Voltage Thermostats) . 10 4.5 Thermal Performance tests . 10 4.5.1 General Conditions 10 4.5.2 Differential Tests . 11 4.5.3 Cycle Rate Test . 11 4.5.4 Droop Test (Heating and Cooling) . 12 4.5.5 Test Data Forms . 12 DC 3-2013 Page ii 2014 Na
18、tional Electrical Manufacturers Association Section 5 MARKING 15 5.1 Markings Plainly Visible . 15 5.2 Markings 15 5.3 Labels, Stampings, or Decals . 15 5.4 When there are More than Two Wiring Connections 15 5.5 Markings for the Scale and for Adjustments . 15 5.6 Instructions for Installation and Us
19、e 15 Section 6 APPLICATION . 18 6.1 Room Thermostats . 18 6.2 Switches 18 6.3 Low-Voltage Thermostats . 18 6.4 Line-Voltage Thermostats . 18 6.5 Proper Instructions 18 6.6 Connected Electrical Loads 18 6.7 Thermostats with Anticipating Heaters 18 6.8 Selection of Thermostats Based on Performance Tes
20、ts 18 6.9 Selection of the Correct Thermostat for Satisfactory Performance 18 Section 7 NEMA THERMOSTAT TEST EQUIPMENT . 19 7.1 General 19 7.2 Thermostat Test Chamber 19 7.2.1 Thermostat Mounting Panel 19 7.2.2 Heating System . 19 7.2.3 Cooling System . 19 7.2.4 NEMA Standard Values for Air Duct and
21、 Blower System . 19 7.2.5 Air Duct and Blower Characteristics for Evaluating Application Variations . 20 7.2.5 Electrical Terminal Board 20 7.3 Program Controller 20 7.4 Temperature and Event Recorder. 20 7.5 Test Loads, Supplies, and Controls 20 DC 3-2013 Page iii 2014 National Electrical Manufactu
22、rers Association Foreword This standards publication defines the basic standards for rating, classification, construction, test, and performance of wall-mounted room thermostats and describes the thermostat test equipment necessary to test thermostat operation and performance. It has been developed
23、in the public interest and is designed to promote a better understanding between the manufacturer and the user and to assist the user in selecting and obtaining the proper thermostat for his or her particular application. If a value for measurement as given in this Standards Publication is followed
24、by an equivalent value in other units, the first stated value is to be regarded as the requirement. The given equivalent value may be only approximate. These standards are periodically reviewed by the Residential Controls Section of NEMA for any revisions necessary to keep them up-to-date with advan
25、cing technology. Proposed or recommended revisions should be submitted to: Senior Technical Director, Operations National Electrical Manufacturers Association 1300 North 17th Street Suite 900 Rosslyn, Virginia 22209 NEMA DC 3-2013 revises and supersedes the NEMA DC 3-2013 Wall-Mounted Room Thermosta
26、ts. This standards publication was developed by the Residential Controls Section. Section approval of the standard does not necessarily imply that all section members voted for its approval or participated in its development. At the time it was approved, the group was composed of the following membe
27、rs: Braeburn Systems LLC Emerson Electric Company, White-Rodgers DivisionSt. Louis, MO Honeywell, Inc.Golden Valley, MN DC 3-2013 Page iv 2014 National Electrical Manufacturers Association History of Standards The Residential Controls Section of NEMA was formed in 1940 to promote the standardization
28、 of products within the scope of the Section. These product standards cover definitions, ratings, performance, testing, and dimensions. NEMA standards are voluntary and are designed to eliminate misunderstandings between the purchaser and the manufacturer. This publication is one of a series sponsor
29、ed by the Residential Controls Section. Other publications in this series are identified as Pub. No. DC XX (followed by the year of issue). The development of NEMA standards for room thermostats was prompted by the need for a basic set of standards for construction and performance that were not cove
30、red by other standards. Action was first taken in 1941 to develop a standard for room thermostats. The standard was published in 1948 and covered low-voltage and line-voltage room thermostats. It was revised several times. The need for separate standards to cover line-voltage electric-heat room ther
31、mostats became evident with the growth and acceptance of electric heat. NEMA DC 15 was first published in 1968 and covered only line-voltage electric-heat room thermostats. It became apparent that a more logical division in the standards for room thermostats would be to incorporate all line-voltage
32、room thermostats in one publication and low-voltage room thermostats in another. Therefore, NEMA DC 3, covering only low-voltage room thermostats, and NEMA DC 15, covering only line-voltage room thermostats, were published in 1972. In 1981, a review of DC 3 and DC 15 indicated that there was a subst
33、antial similarity in definitions, functions, and testing of both line-voltage and low-voltage thermostats. Consequently, it was deemed practical to again consolidate all wall-mounted room thermostats into a single standard, DC 3-1984. The current publication, DC 3-2013 is published in accordance wit
34、h NEMAs policy of periodic review and revision to keep NEMA standards contemporary with industry needs and technological advancement. It replaces the 2008 edition. DC 3-2013 Page 1 2014 National Electrical Manufacturers Association Section 1 GENERAL 1.1 SCOPE This standards publication covers self-c
35、ontained, electrical and electronic, wall-mounted room thermostats for controlling the temperature of the space in which the thermostat is mounted by controlling the applied energy for heating or cooling. 1.2 REFERENCES The following publications are adopted in whole or in part as indicated, by refe
36、rence in this standards publication, and are available from the organizations below. 1.2.1 Normative References The following normative documents contain provisions, which through reference in this text, constitute provisions of this standards publication (SP). By reference herein these publications
37、 are adopted, in whole or in part as indicated, in this SP. National Fire Protection Association (NFPA) Batterymarch Park Quincy, MA 02269 ANSI/NFPA 70* National Electrical Code Underwriters Laboratories, Inc. (UL) 333 Pfingsten Road Northbrook, IL 60062 UL 310 Quick-Connect Terminals ANSI/UL 486A-4
38、86B Wire Connectors ANSI/UL 514A* Metallic Outlet Boxes, Electrical ANSI/UL 514C* Nonmetallic Outlet Boxes, Flush-Device Boxes, and Covers UL 873 Electrical Temperature-Indicating and -Regulating Equipment ANSI/UL 60730-1 Automatic Electrical Controls for Household and Similar Use, Part 1: General R
39、equirements ANSI/UL 60730-2-9 Automatic Electrical Controls for Household and Similar Use Part 2-9: Requirements for Temperature Sensing Controls *Also available from the American National Standards Institute (ANSI), 25 West 43rd Street, New York, NY 10036. 1.3 DEFINITIONS This section contains defi
40、nitions of terms used in this document as well as commonly used industry terms. actuation: Denotes a movement of the actuating member of the control by the user, by hand, by foot, or by any other human activity. actuating member: Denotes that part which is manually or similarly moved, pushed, or tur
41、ned to cause initiation of a control action for the purpose of varying or changing a controlled parameter. DC 3-2013 Page 2 2014 National Electrical Manufacturers Association anticipating heater: A means for adding heat within the thermostat to provide heating anticipation or cooling anticipation. a
42、nticipation, cooling: The ability of a thermostat to initiate cooling at a lower temperature and in advance of the time that the air temperature at the thermostat would normally cause the thermostat to initiate cooling. This may be accomplished by thermal means or by an electronic algorithm in the m
43、icroprocessor. anticipation, heating: The ability of a thermostat to terminate heating at a lower temperature and in advance of the time that the air temperature at the thermostat would normally cause the thermostat to terminate heating. This may be accomplished by thermal means or by an electronic
44、algorithm in the microprocessor. battery backup: Provision in a thermostat, generally an electronic thermostat, that permits the thermostat to retain program memory or clock time, or both, when electric power to the thermostat is interrupted. capacitor backup: Provision in an electronic thermostat t
45、hat permits the thermostat to retain program memory or clock time, or both, by a capacitor which may hold the memory for a few minutes up to several hours when electric power to the thermostat is interrupted. The length of time determines the size of the capacitor. changeover, automatic: The provisi
46、on for changing from heating to the cooling mode, or vice versa, automatically. changeover, manual: The provision for changing from heating or cooling mode, or “off” by means of manual switches or devices, or by a menu and selection by a keyboard. changeover/reversing valve: A valve in a heatpump sy
47、stem that is operated by the thermostat to reverse the cycle of a heat pump to change from heating to cooling operation or vice versa. class 2 remote control and signal system:* A system, depending on the voltage, that has the current limited as follows: 1. Maximum 20 volts, 5 amperes. Circuits in w
48、hich the open-circuit voltage does not exceed 20 volts and having overcurrent protection of not more than 5 amperes rating. Where the current supply is from a transformer or other device having energy-limiting characteristics and approved for the purpose, or from primary batteries, the overcurrent p
49、rotection is not required. 2. 20 to 30 volts, 3.3 amperes. Circuits in which the open-circuit voltage exceeds 20 volts but does not exceed 30 volts and having overcurrent protection of not more than 3.3 amperes rating. Where the current supply is from a transformer or other device having energy-limiting characteristics and approved for the purpose, or from primary batteries, the overcurrent protection is not required. * Based on Section 725.41 Tables 11 (A) and 11 (B) for Power Limitation for AC and DC Circuits from the National Electrical Code, NFPA 70. control poi
