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GB/T 32224-2020 English PDF (GB/T 32224-2015)

GB/T 32224-2020_English: PDF (GB/T32224-2020)
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GB/T 32224-2020English1299 Add to Cart 8 days [Need to translate] Heat meters Valid GB/T 32224-2020
GB/T 32224-2015English320 Add to Cart 0--9 seconds. Auto-delivery Heat meters Obsolete GB/T 32224-2015


BASIC DATA
Standard ID GB/T 32224-2020 (GB/T32224-2020)
Description (Translated English) Heat meters
Sector / Industry National Standard (Recommended)
Classification of Chinese Standard P46
Classification of International Standard 91.140.10
Word Count Estimation 70,752
Date of Issue 2020-11-19
Date of Implementation 2021-10-01
Older Standard (superseded by this standard) GB/T 32224-2015
Quoted Standard GB/T 191; GB/T 1800.2; GB/T 2423.1; GB/T 2423.2; GB/T 2423.3; GB/T 2423.4; GB/T 4208-2017; GB 4706.1-2005; GB/T 7307; GB/T 9124.1; GB/T 9124.2; GB/T 9254; GB/T 17241.6; GB/T 17626.2; GB/T 17626.3; GB/T 17626.4; GB/T 17626.5; GB/T 17626.6; GB/T 17626.8
Drafting Organization China Urban Construction Research Institute Co., Ltd.
Administrative Organization National Urban Heating Standardization Technical Committee
Regulation (derived from) National Standard Announcement No. 26 of 2020
Proposing organization Ministry of Housing and Urban-Rural Development of the People's Republic of China
Issuing agency(ies) State Administration for Market Regulation, National Standardization Administration
Summary This standard specifies the terms and definitions, symbols, technical characteristics, requirements, test methods, inspection rules, signs, packaging, transportation and storage of heat meters. This standard applies to the manufacture and inspection of heat meters using water as the medium. When the medium used is other liquids, this standard can be implemented after obtaining the mass enthalpy and density parameters of the liquid.

BASIC DATA
Standard ID GB/T 32224-2015 (GB/T32224-2015)
Description (Translated English) Heat meters
Sector / Industry National Standard (Recommended)
Classification of Chinese Standard P40
Classification of International Standard 91.140.60
Word Count Estimation 52,511
Date of Issue 2015-12-10
Date of Implementation 2016-11-01
Drafting Organization Ltd., Shenyang Institute of Energy Technology Co., Ltd., the long-mao Automation (Dalian (Group) Co., Ltd.), Shenyang Science and Technology Development Co., Ltd., Shenyang Science and Technology Development Co., ) Limited, Lierda Technology Co., Ltd., Beijing Geran Instrument Co., Ltd., Beijing Debao Haote Energy Technology Co., Ltd., Henan Xintian Technology Co., Ltd., Tianjin Institute of Metrology Supervision and Inspection, Xuzhou Run Technology Development Co., Company, Beijing Tim Ruixiang Instrument Co., Ltd., Siemens (China) Co., Ltd.
Administrative Organization National Standardization Technical Committee for Urban Heating (SAC/TC 455)
Regulation (derived from) National Standard Announcement 2015 No.38
Proposing organization Ministry of Housing and Urban-Rural Development of the People's Republic of China
Issuing agency(ies) General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China


GB/T 32224-2020 (Calorimeter) ICS 91:140:10 P46 National Standards of People's Republic of China Replace GB/T 32224-2015 Calorimeter Heatmeters 2020-11-19 released 2021-10-01 implementation State Administration for Market Regulation Issued by the National Standardization Management Committee Table of contents Foreword Ⅰ 1 Scope 1 2 Normative references 1 3 Terms and definitions 2 4 Symbol 4 5 Technical characteristics 5 6 Requirements 9 7 Test method 14 8 Inspection rules 24 9 Marking, packaging, transportation and storage 25 Appendix A (Normative Appendix) Density value and mass enthalpy value of water 28 Appendix B (Normative Appendix) Structure and Installation of Temperature Sensor 30 Appendix C (Normative Appendix) Data Interface and Communication 39 Appendix D (Normative Appendix) Error Test and Calculation of Integral Heat Meter 41 Appendix E (Normative Appendix) Calculator Error Test and Calculation 42 Appendix F (Normative Appendix) Error Test and Calculation of Paired Temperature Sensor 44 Appendix G (Normative Appendix) Flow Sensor Error Test and Calculation 48 Appendix H (Normative Appendix) Electromagnetic Compatibility Test Method 50 Appendix I (Normative Appendix) Flow Disturbance Test Device and Flow Disturbance 57 Preface This standard was drafted in accordance with the rules given in GB/T 1:1-2009: This standard replaces GB/T 32224-2015 "heat meter", compared with GB/T 32224-2015, except for editorial changes, the main technology The changes are as follows: ---Deleted the content of 0:3m3/h in common flow (see Table 1 in the:2015 edition); ---Added the definition of switching temperature (see 3:3:9); ---Added the requirements for the length tolerance of the flow sensor (see Table 1); ---Modified the requirements for display resolution (see 6:1:2, 5:2:2:1 and 5:2:2:2 of the:2015 edition); ---Modified the requirements and test methods for strength and tightness testing (see 6:3, 7:4, 5:4, 6:4 of the:2015 edition); ---Modified the maximum allowable error formula of the overall heat meter (see 6:4:1, 5:5:1:2 in the:2015 edition); ---Added the maximum allowable error formula of the combined heat meter (see 6:4:2:1); ---Modified the calculator's maximum allowable error formula (see 6:4:2:2, 5:5:2 of the:2015 edition); ---Modified the maximum allowable error formula of the paired temperature sensor (see 6:4:2:3, 5:5:3 in the:2015 edition); ---Modified the maximum allowable error formula of the flow sensor (see 6:4:2:4, 5:5:4 in the:2015 edition); ---Added the calculation formula for the maximum allowable error of the combination of the calculator and the paired temperature sensor (see 6:4:2:5); ---Added the requirements and test methods for the verification of the switching temperature value and the switching temperature difference of the cooling and heating meter (see 6:5, 7:6); ---Modified the requirements for power supply voltage (see 6:7:3, 5:7:3 of the:2015 edition); --- The requirement for repetitiveness has been deleted (see 5:8 in the:2015 edition); ---Added the requirements and test methods for the response performance of the fast response heat meter (see 6:9, 7:10); ---Modified the requirements for static magnetic field (see 6:10:3, 5:10:3 of the:2015 edition); ---Modified the requirements for the enclosure protection level (see 6:10:5, 5:10:5 in the:2015 edition); ---Modified the requirements for seals (see 6:10:6, 5:10:6 in the:2015 edition); ---Modified the requirements for data interface and communication (see 6:11, 5:12 of the:2015 edition); ---Added the requirements and test methods for constant humidity and heat (see 6:12:3, 7:13:3); ---Added requirements and test methods for radio disturbance test (see 6:13:2, H:6); ---Added requirements and test methods for flow disturbance test (see 6:14, 7:15); ---Modified the battery life test method and calculation requirements (see 7:8:2, 6:7 of the:2015 edition); ---Modified the name and requirements of the basic durability test (see 7:9:2:3, 6:9:1:2 in the:2015 edition); ---Modified the name and requirements of the additional durability test (see 7:9:2:4, 6:9:1:3 of the:2015 edition); ---Added the requirements of accelerated durability test method (see 7:9:2:5); ---Modified the requirements and test methods of the temperature sensor durability test (see 7:9:3, 6:9:2 in the:2015 edition); ---Modified the density and enthalpy table of water and indicated the source of the data (see Appendix A); ---Modified the standard structure size drawing of DS temperature sensor (see Figure B:1,:2015 version of Figure B:1); ---Modified the overall requirements of data interface and communication (see Appendix C); ---Modified the measurement point requirements for the overall test volume of the heat meter (see Table D:1,:2015 edition D:3); ---Added the requirements for the measurement points of the cold meter during the overall test of the heat meter (see Table D:1); ---Added the requirements for the confirmation of the displayed value during the overall test of the heat meter (see D:2:3); ---Modified the test temperature point requirements of the heat meter calculator (see Table E:1, E:3 of the:2015 edition); ---Added the requirements for the test of the cold and heat meter calculator (see E:1); ---Added the requirements for the test temperature point of the cold meter calculator (see Table E:1); ---Added the requirements for the analog flow signal during the calculator test (see E:2:3); ---Modified the temperature test range of the temperature sensor (see F:2:1, F:3:1 in the:2015 edition); ---Added special requirements for testing flow sensors greater than DN250 (see G:2:1); ---Added the requirements for water temperature changes during the flow sensor test (see G:2:2); --- Modified the electromagnetic compatibility test requirements (see Appendix H, Table 4 of the:2015 edition): This standard was proposed by the Ministry of Housing and Urban-Rural Development of the People's Republic of China: This standard is under the jurisdiction of the National Urban Heating Standardization Technical Committee (SAC/TC455): Drafting organizations of this standard: China Urban Construction Research Institute Co:, Ltd:, Weihai Tiangang Instrument Co:, Ltd:, Guangzhou Baicheng Intelligent Division Technology Co:, Ltd:, Shenyang Hangfa Technology Industrial Co:, Ltd:, Standard Rating Research Institute of Ministry of Housing and Urban-Rural Development, Jumao Automation (Dalian) Co:, Ltd:, Huizhong Instrument Co:, Ltd:, Xintian Technology Co:, Ltd:, Shandong Lichuang Technology Co:, Ltd:, Shenyang Jiade Lianyi Energy Technology Co:, Ltd:, Rena Intelligent Equipment Co:, Ltd:, Jining Five Star Meter Co:, Ltd:, Xuzhou Runwu Technology Development Co:, Ltd: Co:, Ltd:, Liaoning Sky Technology Co:, Ltd:, Dalian Bokong Technology Co:, Ltd:, Beijing Debao Haote Energy Technology Co:, Ltd:, North Jingtian Ruixiangde Metrology Technology Co:, Ltd:, Beijing Jebsen Century Intelligent Technology Co:, Ltd:, Tianjin Institute of Metrology Beijing Public Utilities Research Institute: The main drafters of this standard: Yang Jian, Fu Tao, Tan Wensheng, Ni Zhijun, Zhang Huifeng, Feng Lei, Chen Hui, Fei Zhanbo, Li Mei, Wang Kuilin, Yu Dayong, Liu Ruifeng, Wang Hualiang, Shi Jianjun, Zeng Yongchun, Zhang Lixiang, Xu Defeng, Yang Chenghua, Shi Xin, Zhang Tao: The previous versions of the standard replaced by this standard are as follows: ---GB/T 32224-2015: Calorimeter 1 Scope This standard specifies the terms and definitions, symbols, technical characteristics, requirements, test methods, inspection rules, signs, packaging, transportation and Store: This standard applies to the manufacture and inspection of heat meters using water as the medium: When other liquids are used, the quality of the liquid is obtained After measuring the enthalpy and density parameters, this standard can be implemented: 2 Normative references The following documents are indispensable for the application of this document: For dated reference documents, only the dated version applies to this article Pieces: For undated references, the latest version (including all amendments) applies to this document: GB/T 191 Packaging, Storage and Transportation Graphic Mark GB/T 1800:2 Product Geometric Technical Specification (GPS) Linear Dimension Tolerance ISO Code System Part 2: Standard Tolerance Zone Code and limit deviation table of hole and shaft GB/T 2423:1 Environmental testing of electrical and electronic products Part 2: Test methods Test A: Low temperature GB/T 2423:2 Environmental testing of electric and electronic products Part 2: Test method Test B: High temperature GB/T 2423:3 Environmental Test Part 2: Test Method Test Cab: Constant Damp Heat Test GB/T 2423:4 Environmental testing of electrical and electronic products Part 2: Test method Test Db: Alternating damp heat (12h 12h cycle) GB/T 4208-2017 Enclosure protection grade (IP code) GB 4706:1-2005 Safety of household and similar electrical appliances Part 1: General requirements GB/T 7307 55° unsealed pipe thread GB/T 9124:1 Steel pipe flanges Part 1: PN series GB/T 9124:2 Steel Pipe Flange Part 2: Class Series GB/T 9254 Information Technology Equipment Radio Disturbance Limits and Measurement Methods GB/T 17241:6 Integral cast iron flange GB/T 17626:2 Electromagnetic compatibility test and measurement technology Electrostatic discharge immunity test GB/T 17626:3 Electromagnetic compatibility test and measurement technology Radio frequency electromagnetic field radiation immunity test GB/T 17626:4 Electromagnetic compatibility test and measurement technology Electrical fast transient pulse group immunity test GB/T 17626:5 Electromagnetic compatibility test and measurement technology surge (impact) immunity test GB/T 17626:6-2017 Electromagnetic compatibility test and measurement technology Radio frequency field induced conducted disturbance immunity GB/T 17626:8 Electromagnetic compatibility test and measurement technology Power frequency magnetic field immunity test GB/T 17626:11 Electromagnetic compatibility test and measurement technology Voltage sag, short-term interruption and voltage change immunity test GB/T 26831:1 Community Energy Metering and Collecting System Specification Part 1: Data Exchange GB/T 26831:2 Community Energy Metering System Specification Part 2: Physical Layer and Link Layer GB/T 26831:3 Community Energy Metering and Collecting System Specification Part 3: Professional Application Layer GB/T 26831:6 Community Energy Metering and Collecting System Specification Part 6: Local Bus GB/T 30121-2013 Industrial platinum thermal resistance and platinum temperature sensing element CJJ34 Code for design of urban heating pipe network ......


GB/T 32224-2015 NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA ICS 91.140.60 P 40 Heat meters ISSUED ON: DECEMBER 10, 2015 IMPLEMENTED ON: NOVEMBER 01, 2016 Issued by: General Administration of Quality Supervision, Inspection and Quarantine of PRC; Standardization Administration of PRC. Table of Contents Foreword ... 3  1 Scope ... 4  2 Normative references ... 4  3 Terms and definitions ... 5  4 Technical characteristics ... 9  5 Requirements ... 13  6 Test methods ... 19  7 Inspection rules ... 27  8 Marking, packaging, transportation, storage ... 29  Appendix A (Normative) Density and enthalpy of water ... 31  Appendix B (Normative) Structure and installation of platinum-resistance temperature sensor ... 35  Appendix C (Normative) Optical interface and data communication ... 51  Appendix D (Normative) Test and calculation of measurement accuracy of heat meter ... 53  Appendix E (Normative) Test and calculation of calculator’s accuracy ... 54  Appendix F (Normative) Test and calculation of accuracy of temperature sensor ... 56  Appendix G (Normative) Test and calculation of accuracy of flow sensor ... 60  Heat meters 1 Scope This standard specifies the terms and definitions, technical characteristics, requirements, test methods, inspection rules, marking, packaging, transportation, storage of heat meters. This standard applies to the production and inspection of heat meters which use water as medium. 2 Normative references The following documents are essential to the application of this document. For the dated documents, only the versions with the dates indicated are applicable to this document; for the undated documents, only the latest version (including all the amendments) are applicable to this standard. GB/T 191 Packaging - Pictorial marking for handling of goods GB/T 2423.1 Environmental testing for electric and electronic and electronic products - Part 2: Test methods - Tests A: Cold GB/T 2423.2 Environmental testing for electric and electronic products - Part 2: Test methods - Tests B: Dry heat GB/T 2423.4 Environmental testing for electric and electronic products - Part 2: Test method - Test Db: Damp heat, cyclic (12h + 12h cycle) GB/T 26831.1 Society energy metering for reading system specification - Part 1: Data exchange GB/T 26831.2 Society energy metering for reading system specification - Part 2: Physical and link layer GB/T 26831.3 Society energy metering for reading system specification - Part 3: Dedicated application layer GB 4208-2008 Degrees of protection provided by enclosure (IP code) GB 4706.1-2005 Household and similar electrical appliances - Safety - Part 1: General requirements GB/T 9113 Integral steel pipe flange GB/T 17241.6 Integral cast iron flanges GB/T 17626.2 Electromagnetic compatibility - Testing and measurement techniques - Electrostatic discharge immunity test GB/T 17626.3 Electromagnetic compatibility - Testing and measurement techniques - Radiated, radio-frequency, electromagnetic field immunity test GB/T 17626.4 Electromagnetic compatibility - Testing and measurement techniques - Electrical fast transient/burst immunity test GB/T 17626.5 Electromagnetic compatibility - Testing and measurement techniques - Surge immunity test GB/T 17626.8 Electromagnetic compatibility (EMC) - Part 4-8: Testing and measurement techniques - Power frequency magnetic field immunity test GB/T 17626.9 Electromagnetic compatibility - Testing and measurement techniques - Pulse magnetic field immunity test GB/T 17626.11 Electromagnetic compatibility - Testing and measurement techniques - Voltage dips, short interruptions and voltage variations immunity tests GB/T 17626.29 Electromagnetic compatibility (EMC) - Testing and measurement techniques - Voltage dips short interruptions and voltage variations on D.C. input power port immunity tests CJJ 34 Design code for city heating network JB/T 8622-1997 Technical specification and reference table for industrial platinum thermal resistance JB/T 9329 Basic environmental conditions and testing methods for instruments transportation and storage in the transportation 3 Terms and definitions The following terms and definitions apply to this document. 3.1 Heat meter A meter which is used to measure and display the released or absorbed temperature of water supply and water return of the heat exchange system. 3.9 Calculator A component that receives signals from the flow sensor and the temperature sensor pair for heat calculation, storage, display of heat values as exchanged by the system. 3.10 Temperature difference The difference between the temperature of water supply and water return of the heat exchange system. 3.11 Minimum temperature difference The lower limit of the temperature difference, under which the accuracy of the heat meter shall not exceed the error limit. 3.12 Maximum temperature difference The upper limit of the temperature difference, under which the accuracy of the heat meter shall not exceed the error limit. 3.13 Minimum flowrate Under the condition that the accuracy of the heat meter does not exceed the error limit, the lower limit of flowrate of the water when it flows through the heat meter. 3.14 The permanent flowrate Under the condition that the accuracy of the heat meter does not exceed the error limit, the upper limit of flowrate when the heat meter is continuously operated for a long time. 3.15 4 Technical characteristics 4.1 Heat measurement 4.1.1 Method of heat measurement The heat may be measured by the enthalpy difference method or the thermal coefficient method. 4.1.2 Enthalpy difference method When water flows through an complete heat meter or a combined heat meter which is installed in a heat exchange system, according to the flowrate as given by the flow sensor and the temperature signal of water supply and return as given by the temperature sensor pair as well as the time the water flows, the calculator is used to calculate and display the released or absorbed heat of this system. The released or absorbed heat of this system is calculated according to formula (1): Where: Q - The heat released or absorbed by the system, in Joule (J); qm - The mass flowrate of water which flows through the heat meter, in kilograms per hour (kg/h); qv - The volume flowrate of water which flows through the heat meter, in cubic meters per hour (m3/h); ρ - The density of water which flows through the heat meter, in kilograms per cubic meter (kg/m3); Δh - The difference in enthalpy of water at the temperature of water supply and water return in the heat exchange system, in Joule per kilogram (J/kg); τ - Time, in hours (h). 4.1.3 Thermal coefficient method When water flows through an complete heat meter or a combined heat meter which is installed in a heat exchange system, according to the signal of temperature difference of water supply and water return as given by the temperature sensor pair as well as the total volume (the volume) of water as given by the flow sensor, the calculator is used to calculate and display the 5.2.1.3 The visible height of the displayed number shall not be less than 4 mm. The fractional part of the displayed value shall be clearly distinguishable from the rest of the value. When using display by multiple pages, the value as displayed on each page shall be complete. 5.2.2 Resolution of display 5.2.2.1 In the using mode, the minimum display resolution shall comply with the following requirements: a) Calorific value: 1 kW • h, 1 MW • h or 1 MJ, 1 GJ; b) Temperature value: 0.1 °C; c) Temperature difference: 0.1 K; d) Total volume: 1) Nominal diameter DN15 ~ DN25: 0.01 m3; 2) Nominal diameter DN32 ~ DN400: 0.1 m3. 5.2.2.2 In the verification mode, the minimum display resolution shall comply with the following requirements: a) Calorific value: 0.001 kW • h or 0.001 MJ; b) Temperature value: 0.01 °C; c) Temperature difference: 0.01 K; d) Total volume: 1) Nominal diameter DN15 ~ DN25: 0.00001 m3; 2) Nominal diameter DN32 ~ DN100: 0.0001 m3; 3) Nominal diameter DN125 ~ DN400: 0.001m3. 5.2.2.3 The displayed value and unit of display shall be clearly and definitely marked. The displayed value shall be a valid number. 5.2.3 Display value of heat 5.2.3.1 When the heat meter is continuously operated for 3000 h under the maximum thermal power, the heat shall not exceed the maximum display value. 5.2.3.2 When the heat meter is continuously operated for 1 h under the maximum thermal power, the minimum effective display number shall be added The accuracy of the flow sensor of the grade-1 meter shall not exceed ±3.5%. The accuracy of the flow sensor of the grade-2 and grade-3 shall not exceed ± 5%. 5.6 Admissible pressure loss When the heat meter is operated under the permanent flowrate, the admissible pressure loss is not more than 0.025 MPa. 5.7 Power supply 5.7.1 Basic requirements The heat meter may use either a built-in battery or an external power supply. For heat meters which have a nominal diameter of less than or equal to DN40, it shall use the built-in battery. 5.7.2 Service life of built-in battery The service life of the built-in battery shall be more than (5 + 1) years. 5.7.3 External power supply 5.7.3.1 The externally connected AC power supply’s voltage shall be . The frequency fn = (50 ± 1) Hz. 5.7.3.2 The externally connected DC power supply’s voltage may be (5 ± 0.25) V, (12 ± 0.6) V or (24 ± 1.2) V. 5.8 Repeatability The error of repeatability of the heat meter shall not exceed the maximum admissible error limit. 5.9 Durability The effective life cycle of the heat meter shall be more than 5 years. The effective life cycle shall be assessed by the durability test. 5.10 Safety performance 5.10.1 Power failure protection When the power supply stops supplying power, the heat meter shall be able to save the heat stored before the power failure, the total volume and the corresponding time data, the historical data in 5.3. After the power supply is restored, it shall automatically resume normal operation. 5.10.2 Undervoltage prompt of battery’s voltage When the voltage of the battery drops to the set undervoltage value, the heat meter shall have an undervoltage prompt message and shall be in normal working state. 5.10.3 Resistance to magnetic-field interference When subjected to a magnetic-field interference which has a strength of not more than 100 kA/m, the heat meter shall work normally and the data is normal. 5.10.4 Electrical insulation When the heat meter uses AC power supply, the electrical insulation shall comply with the provisions of category-I appliances in GB 4706.1-2005. 5.10.5 degree of protection of shell The classification of the degree of protection of the shell shall be according to the provisions of GB 4208-2008. For the heat meter which has an environment of use of category-A and category-B, the degree of protection of shell shall be IP54. For the heat meter which has an environment of use of category-C, the degree of protection of shell shall be IP65. For the heat meter which has an environment of use of category-D, the degree of protection of shell shall be IP65/IP68. The degree of protection of the shell of the cooling meter and the meters for heating and cooling shall be IP65. The shell of the heat meter shall have a marking of degree of protection. 5.10.6 Seal The heat meter shall have a reliable seal. Without damaging the seal, it shall not dismantle the heat meter and relevant components. 5.11 Optical interface The heat meter shall have an optical interface. Its structural and optical characteristics shall comply with the provisions of Appendix C. 5.12 Data communication The data communication of the heat meter may be equipped with interfaces such as M-bus, RS-485, wireless transmission. The communication protocol shall comply with the provisions of Appendix C. 6.2.2 Resolution of display 6.2.2.1 Visually check the heat meter. In the using mode, the resolution of display shall comply with the provisions of 5.2.2.1. 6.2.2.2 Output the parameters of the heat meter from the optical interface of the heat meter. In the verification mode, the resolution of display shall comply with the provisions of 5.2.2.2. 6.2.3 Displayed value of heat Make the heat meter continuously operate at the maximum thermal power for 1 h. Respectively record the displayed value of heat at the beginning and end of the test. Use visual inspection and calculation. The displayed value of heat shall comply with the requirements of 5.2.3. 6.3 Data storage Simulate the operation of the heat meter for 18 months. Check the content and period of the data storage, which shall meet the requirements of 5.3. 6.4 Strength and tightness 6.4.1 Strength For the heat meter which is installed in the closed pipeline, load the medium of water which has a temperature of the upper temperature limit minus 5 °C ~ 15 °C and a pressure of 1.5 times the maximum working pressure. After 30 minutes of stabilization, check the heat meter, which shall comply with the requirements of 5.4. 6.4.2 Tightness For the heat meter, load the medium of water which has a temperature of the upper temperature limit minus 5 °C ~ 15 °C and a pressure of 1.5 times the maximum working pressure. After 30 minutes of stabilization, check the heat meter, which shall comply with the requirements of 5.4. 6.5 Accuracy 6.5.1 Measurement accuracy of heat meter The test and calculation of the measurement accuracy of the heat meter shall be carried out according to the provisions of Appendix D. 6.5.2 Accuracy of calculator The test and calculation of the accuracy of the calculator shall be carried out a) Install the heat meter on the test bench to run it normally under the following conditions: 1) Flowrate: the permanent flowrate; 2) Water temperature: The heat meter is (50 ± 5) °C. The cooling meter is (15 ± 5) °C. b) During the test, first empty the air from the heat meter, differential pressure gauge, pipeline. When the pressure is stable, measure the pressure difference between the front and back pressure measuring points. c) The test shall separately measure the pressure difference between the front and back pressure measuring points when installing the heat meter and not installing the heat meter (replaced by a straight pipe segment of the same diameter). The difference between the two measured values is the admissible pressure loss of the heat meter. d) Admissible pressure loss shall comply with the provisions of 5.6. 6.7 Power supply The test of service life of the built-in battery is performed as follows: a) Install the heat meter on the test bench, to run it normally under the following conditions. b) Flowrate: the permanent flowrate; c) Water temperature: The heat meter is (50 ± 5) °C. The cooling meter is (15 ± 5) °C. d) Measure the working curve of power supply’s current of the heat meter for no less than 10 complete working cycles. Use 80% of the rated capacity value of the battery as the reference data, calculate the effective value of the power supply’s current of the heat meter and the corresponding battery life, which shall comply with the provisions of 5.7.2. 6.8 Repeatability According to the test requirements for the measurement accuracy of the heat meter, at the same test conditions and the same test point, test the accuracy of the heat meter for 3 times. The maximum difference between any 2 test values shall meet the requirements of 5.8. 6.9 Durability 6.9.1 Durability of flow sensor b) The flowrate shall be the maximum flowrate qs of the heat meter. The deviation is ; c) The flow sensor runs continuously for 300 h. 6.9.1.4 After the durability test A and the durability test B are completed, the heat meter shall be at (50 ± 5) °C and the cooling meter shall be at the water temperature of (15 ± 5) °C; check the accuracy of the flow sensor of the heat meter, which shall meet the requirements of 5.5.4. 6.9.2 Durability of temperature sensor The durability test of the temperature sensor shall comply with the following requirements: a) Place the temperature sensor pair in the constant-temperature bath. Slowly increase the temperature to the upper limit of the product's calibrated use temperature. Then place it in room-temperature air. Slowly reduce the temperature to the lower limit of the product's calibrated use temperature. Repeat the temperature rise-fall for 10 times. b) During the test, the temperature sensor shall have an immersion depth of 90% ~ 99% of its total length at each temperature boundary. Meanwhile the temperature shall be corrected. c) After the test is completed, check whether the accuracy of the temperature sensor pair complies with the provisions of 5.5.3. The insulation performance shall comply with the provisions of 4.2.3.3. 6.10 Safety performance 6.10.1 Power failure protection Make the calculator run for 24 h under the maximum temperature difference and the permanent flowrate condition. Then stop running for 24 h. Record the stored data of the heat meter. Interrupt the heat meter’s power supply for more than 24 h. Restore the normal power supply to the heat meter. Check the stored data before and after the interruption of power supply, which shall comply with the provisions of 5.10.1. 6.10.2 Undervoltage prompt of battery The test of undervoltage prompt of battery shall meet the following requirements: a) The test instrument is: - Environment category; - Marking of degree of protection; - Marking and number of meter manufacture license. 8.2 Packaging On the outside of the packaging box, according to the requirements of GB/T 191, print the marks of upwards, avoid moisture, handle with care; indicate the manufacturer’s name, address, marking and number of meter manufacture license, net weight, data of production. The accompanied files in the box shall include: - Product’s certificate; - Instruction manual; - Packing list. 8.3 Transportation The heat meter shall be placed according to the marks during transportation. It shall not be directly affected by rain, frost or fog. It shall not be damaged by extrusion or impact. 8.4 Storage 8.4.1 The height of the product mat from the ground shall not be less than 0.3 m, the distance from the four walls shall not be less than 1 m, the distance from the heating equipment shall not be less than 2 m. 8.4.2 The environmental conditions of the warehouse shall comply with the following provisions: a) Temperature: - Environment category-A and environment category-C: 5 °C ~ 55 °C; - Environment category-B and environment category-D: -25 °C ~ 55 °C. b) Relative humidity: < 80%. c) There shall be no acid, alkali, flammable, explosive, toxic, corrosive items in the warehouse. It shall avoid the actions of strong electromagnetic fields and direct sunlight. Appendix C (Normative) Optical interface and data communication C.1 Optical interface The optical interface shall comply with the provisions of GB/T 26831.1. C.2 Wakeup of optical interface After the optical interface of the heat meter receives the initial wakeup message as specified below, the optical interface shall be able to wake up and enter normal operation state: a) The wakeup message is a string of NUL characters (code 00 H) in the time period of 2.1 s ~ 2.3 s. b) The maximum admissible delay between two NULL characters in this message is 5 ms. c) After the last character of the wakeup message, the wakeup device shall wait for 1.5 s ~ 1.7 s, until the request message can be sent. d) The baud rate of wakeup communication is 300 bit/s or 2400 bit/s. After wakeup, it uses the data communication as specified by C.3 for data communication. e) End of transmission: After the heat meter sends the data message, the data transmission is completed. If the transmission is wrong, the wakeup device shall wait for 1.5 s before sending a new wakeup signal. C.3 Data communication C.3.1 Basic requirements for transmission C.3.1.1 Sequence of transmission: For all multibyte data fields, it shall transmit the lower byte first and then the upper byte. C.3.1.2 Transmission response: Each communication is initiated by the master station issuing a request command frame to the slave station as selected based on the information frame address field, the requested slave station responds after receiving the command. Response delay after receiving the command frame Td: 20 ms ≤ Td ≤ 500 ms. Appendix E (Normative) Test and calculation of calculator’s accuracy E.1 Standard device of electrical signal The standard device of electrical signal shall comply with the provisions of 6.1.2. E.2 Environmental conditions The test is based on the following environmental conditions: Indoor temperature: 15 °C ~ 35 °C; Relative humidity: 25% ~ 75%; Atmospheric pressure: 80 kPa ~ 106 kPa. E.3 Measuring point The test of calculator shall be performed under the following conditions: a) The 3 measuring points at the return water’s temperature of θmin + 5 °C, and the temperature difference of Δθmin, 5 K, 20 K; b) The 3 measuring points at the water supply’s temperature of θmax - 5 °C, and the temperature difference of 10 K, 20 K, Δθmax; c) The water flowrate is any point within the range of qi ~ qs. E.4 Test E.4.1 For the accuracy test, make 3 measurements at each point. E.4.2 Each measurement includes the reading of the standard device of the electrical signal and the effective reading of the calculator. E.4.3 For the heat meter that cannot directly connect the electrical signal, in addition to the above method, it may also use the indicated value of the temperature difference between the simulated flow signal of the heat meter and that as provided actually, calculate it, use it as the standard heat value as provided to the calculator, to check the calculation error of the calculator. E.4.4 If the temperature sensor and the calculator are not separable, it may use the test conditions of the entire meter of the component to carry out test. The than 90% of its total length. F.4 Test F.4.1 For accuracy test, make 3 measurements at each point. F.4.2 Each measurement includes a reading of the standard device of temperature and an effective reading of the temperature sensor. F.4.3 When the temperature sensor and calculator are not separable, the components may be tested using the test conditions of this Appendix. The absolute value of the difference between the temperature value measured by the temperature sensor pair at each temperature point and the temperature value measured by the standard thermometer shall not exceed 2 °C. The difference of the temperature as measured at the same point by the water supply temperature sensor and the water return temperature sensor of the temperature sensor pair shall satisfy the accuracy requirements that the minimum temperature difference is between the sum of the formula (8) and (9). F.4.4 When measuring temperature, it shall, according to the provisions of Appendix C, use the optical interface to enter and exit the test mode. Follow the provisions of the communication protocol to send high-precision temperature data to the master station, synchronize the data. F.5 Calculation of test result F.5.1 Error of single temperature sensor The kth basic error of the jth measuring point of the temperature sensor is calculated according to the formula (F.1). The basic error of the jth measuring point is calculated according to the formula (F.2). The basic error of the temperature sensor is calculated according to the formula (F.3). Where: Rjk - The kth basic error of the jth measuring point of the temperature sensor, in degrees Celsius (°C); θjk - The kth reading of the temperature sensor at the jth point j (j = 1, 2...n), (k = 1, 2...m), in degrees Celsius (°C); θsjk - The kth reading of the standard device at the jth point, in degrees Celsius (°C). Appendix G (Normative) Test and calculation of accuracy of flow sensor G.1 Standard device of flowrate G.1.1 The standard device of flowrate shall comply with the provisions of 6.1.2. G.1.2 When testing, the front and rear pipelines of the flow sensor shall be straight pipe segments. The length of the straight pipe segment shall be according to the provisions of the measured flow sensor. G.2 Environmental conditions The test is based on the following environmental conditions: Indoor temperature: 15 °C ~ 35 °C; Relative humidity: 25% ~ 75%; Atmospheric pressure: 80 kPa ~ 106 kPa. G.3 Tested water temperature of flow sensor The test is carried out at the following water temperatures: a) Heat meter: Exit-factory inspection: (50 ± 5) °C; Type inspection: (θmin + 5) °C; (50 ± 5) °C; (85 ± 5) °C. b) Cooling meter: Exit-factory inspection: (15 ± 5) °C; Type inspection: (5 ± 1) °C; (15 ± 5) °C. c) Meters for heating and cooling: Exit-factory inspection: (50 ± 5) °C; Type inspection: (5 ± 1) °C; (15 ± 5) °C; (50 ± 5) °C; (85 ± 5) °C. G.4 Measurement point of flowrate ......

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