Some standard content:
National Metrology Verification Regulation of the People's Republic of China Heat Energy
Heat Meters
JJG225--2001
1—10—1
Verification Regulation of Heat Meters
Verification Regulation of Heat MetersJJG 225—2001
Replaces JJG 225--1992
This regulation was approved by the General Administration of Quality Supervision, Inspection and Quarantine on December 4, 2001, and came into effect on March 1, 2002. Unit: National Technical Committee on Flow and Capacity Measurement Main drafting unit: China National Institute of Metrology Participating drafting units: Beijing Metrology and Testing Institute Liaoning Metrology and Testing Institute
Shandong Metrology and Testing Institute
Daqing Lianyi Weihua High-tech Co., Ltd.
Guangzhou Baicheng Intelligent Technology Co., Ltd.
Tsinghua Tongfang Co., Ltd.
This regulation is entrusted to the National Technical Committee on Flow and Capacity Measurement for interpretation 1-10- 2
The main drafter of this regulation:
Wang Dongwei
(China Institute of Metrology)
Participating drafters:
Zhai Xiuzhen
Zhang Liqian
Zang Lixin
Gu Zukang
He Shaowen
Tan Wensheng
Lv Ruifeng
(China Institute of Metrology)
(China Institute of Metrology)
(Beijing Metrology and Testing Institute)
(Liaoning Institute of Metrology)
(Shandong Metrology and Testing Institute)
(Daqing Lianyi Weihua High-tech Co., Ltd.) (Guangzhou Baicheng Intelligent Technology Co., Ltd.) (Tsinghua Tongfang Co., Ltd.)
References,
Terms and definitions
Heat meter ·
Components of heat meter…
Nominal operating conditions
Total quantity verification·
Component verification·
Working principle·
Structure·
Calculation formula of heat energy
5Metering performance requirements
-10—4
10—-4
1-10—4
1-- -10—4
1-—10—4
—10—4
—10—5
-10—5
-10—5
1-10—5
1-10--5
110—5
The sealing and strength of the flow sensor 1—10—5The accuracy level of the heat meter……
1--10--5
Error limit of heat meter
Resilience E of non-impeller flow sensor,
Temperature limit of heat meter
Maximum pressure drop of flow sensor
General technical requirements
Control of measuring instrument
Verification conditions·
Verification items·
Verification methods…
Processing of verification results
Verification cycle·
Appendix A
Appendix B
Appendix C
Type identification and prototype test
1-10--6
1-10—6
1—10—6
1 --10---6
1—10—6
....... 1--10—6
1—10—7
1-10-7
1—10—9
1--10--9
.... 1—10—9
Table of water density and density…………． ． --10—.Table of heat coefficient
10--14
1 -10— 3
Calibration procedure for heat meter
This procedure refers to the international recommendation R75 "Heat meter" (draft) (May 2001) of the International Organization of Legal Metrology (OIML), and adds or deletes a small amount of content in accordance with my country's national conditions. 1 Scope
This regulation applies to the initial verification, subsequent verification, in-use inspection, finalization and prototype testing of heat meters. The verification of heat meters used to measure absorbed heat can refer to this regulation.
2 References
This specification references the following documents
1.OIML R75--2001
Heat meters (Draft) (OIML
R75--2001 Heat meters) (Draft) 2.EN 1434—1997
Heat meters)
3.GB 2423-1989
4.GR 6587—1986
Heat meters
(EN1434—1997
Basic environmental testing for electric and electronic products
Environmental testing for electronic measuring instruments
5.GB/T 17626-1998
6.GB/T 8622—1997
Electromagnetic compatibility test and measurement technology
Industrial platinum resistance temperature sensor
7.GB/T 778.3-1996
Test methods and test equipment
Cold water meter Part 3: Test
When using this procedure, attention should be paid to the use of the current valid versions of the above-mentioned references.
3 Terms and definitions
3.1 Heat meterHeat meter
A measuring instrument used to measure and display the heat released by the heat-carrying liquid in the heat exchange circuit.
3,1,1 Combined heat meterCombined heat meterA heat meter composed of an independent flow sensor, a paired temperature sensor and a calculator.
-Complete heat meter The heat meter is composed of a flow sensor, a paired temperature sensor and a calculator, and the combination is inseparable in whole or in part. 3.2 Sub-assemblies of a heat meter 3.2.1 Flow sensor
A component used to generate a flow signal of the heat-carrying liquid in a heat exchange circuit. The signal is a function of the volume or mass of the heat-carrying liquid, or a function of the volume flow rate or mass flow rate.
3.2.2 Paired temperature sensorpairA component used to simultaneously collect the temperature signals of the heat-carrying liquid at the inlet and outlet in a heat exchange circuit.
3.2.3 Calculator
A component used to receive the signals of the flow sensor and the paired temperature sensor, and to calculate, accumulate, store and display the heat released in the heat exchange circuit.
3.3 Rated operating conditions 3.3.1 Limits of temperature rangeMaximum the upper limit of the3.3.1.1
temperature range
The maximum permissible temperature of the heat-carrying liquid flowing through the heat energy meter. At this temperature, the heat energy indicated value does not exceed the maximum permissible error. the3.3.1.2
temperature range
The minimum permissible temperature of the heat-carrying liquid flowing through the heat energy meter. At this temperature, the heat energy indicated value does not exceed the maximum permissible error. 3.3.2Limits of temperature difference3.3.2.1 Temperature difference A3 the temperature differenceThe difference between the inlet temperature and the outlet temperature of the heat-carrying liquid in the heat exchange circuit.
Upper temperature limit△max the upper limit of the tem-3.3.2.2
perature difference
The maximum permissible temperature difference, at which temperature difference and within the upper limit of the thermal power, the heat energy meter does not exceed the maximum permissible error. 3.3.2.3 Lower limit of temperature difference△0 min the lower limit of the tem-perture difference
Minimum permissible temperature difference, under which the heat meter does not exceed the maximum permissible error.
3.3.3 Limit of flow-rate3.3.3.1 Upper limit of flow9, the upper limit of the flow-rateThe maximum flow rate at which the heat meter can operate for a short period of time (<1 hour/day and <200 hours/year) without exceeding the maximum permissible error.
flow-rate
Usual flow (rated flow)9, the maximum flow rate at which the permanent heat meter can operate continuously without exceeding the maximum permissible error.
3.3.3.3 Minimum flow q, the lower limit of the flow-rateThe minimum flow rate at which the heat meter can operate without exceeding the maximum permissible error.
Upper limit of thermal power P, the upper limit of the thermalThe maximum thermal power at which the heat meter can operate without exceeding the maximum permissible error.
Maximum admissible working pressureMaximum admissibleworking-ing pressure (MAP)
The maximum pressure that a heat meter can sustain when operating at the upper temperature limit.
Maximum pressure lossAp maximum Pressure lossThe pressure loss caused by the heat-carrying liquid flowing through the heat meter when the heat meter is operating at the normal flow rate.
MaximumpermissibleerrorMaximumpermissibleerrorThe limit value of the allowable error of the heat meter.
Total quantity verification
The method of directly verifying the calorific value of the heat meter is called total quantity verification.
Component verification
The method of verifying the parameters of the flow sensor, temperature sensor and integrator that make up the heat meter as components of heat and verifying them separately according to the components or component combinations is called component verification. 4 Overview
Working Principle
The working principle of the heat energy meter is: the paired temperature sensors are installed on the pipes of the inlet and outlet of the heat exchange circuit respectively, and the flow sensor is installed on the inlet or outlet pipe; the flow sensor sends a flow signal, the paired temperature sensor gives the temperature signal of the inlet and outlet, and the calculator collects the flow signal and temperature signal; after calculation, the heat value released by the heat-carrying liquid from the inlet to the outlet is displayed. 4.2
The heat energy meter is mainly composed of a flow sensor, a paired temperature sensor and a calculator.
The heat energy meter can generally be divided into a body heat energy meter and a combined heat energy meter according to the structural type.
Calculation formula of heat energy
The calculation formula of heat energy has the following two forms: Q=
Where: Q
Ah·de
Released heat, kJ;
Mass flow rate of heat-carrying liquid flowing through the heat energy meter, kg/s;
% and +5%
1 For level 1 meter 4, ≥100m2/h.
2 9 is the flow rate.
Error limit E of flow sensor.
1% and ≤±5%
± (2 + 0. 02 )
1% and ≤±5%
±13+0.05-
1% and ≤±5%
Note: For level 1 meter 9, ≥100m2/h.
In the formula: Q
-the difference in specific melting value of the heat-carrying liquid corresponding to the inlet temperature and the outlet temperature in the heat exchange circuit, kJ/kg (the flame value and density table of water are shown in Appendix B);
time, s.
-the amount of heat released, J or kW·h;
V-the volume through which the heat-carrying liquid flows, m2;
A--the temperature difference between the inlet and outlet of the heat-carrying liquid in the heat exchange circuit;
thermal coefficient, which is a function of the heat-carrying liquid at the corresponding temperature, temperature difference and pressure, [J/m2·) or kW.h/(m3℃), the thermal coefficient k value of water is shown in Appendix C. Note:
1When looking up the thermal coefficient table, linear interpolation is allowed. 2The volume measurement position in the formula is at the outlet of the heat exchange circuit, otherwise, density correction should be made.
3The calculation formula of the thermal coefficient table value in Appendix C is derived from the European standard EN1434 "Heat Energy Table".
5 Metering performance requirements
The sealing and strength of the flow sensor
Should be able to withstand the sealing and water pressure strength test without leakage, seepage or damage.
5.2 Accuracy level of heat meter
When calibrated by total amount, the accuracy level and the maximum allowable relative error E are listed in Table 1.
5.2.2When calibrated by component, the accuracy level and the maximum allowable relative error E of each component are listed in Table 2. Table 1
Error limit E of paired temperature sensors.
The temperature difference error of paired temperature sensors shall meet 0.5+3
18min）%
The temperature error of a single temperature sensor shall meet ± (0.30+0.005/81)c
4+4+0.05）
Calculator error limit Ec
±(0.5+%m）%
1—10—5
Error limit of heat meter
The error limit of the heat meter tested in use is twice the above error limit (i.e., twice the maximum allowable error).
Repeatability E, 5.4 of non-impeller flow sensor The repeatability of non-impeller flow sensor shall not be greater than half of the maximum allowable error.
Note: For impeller flow sensor, repeatability may not be required. The lower limit of the temperature of the heat meter
The lower limit of the temperature difference Agmin of the heat meter is generally 3℃C. The maximum pressure drop of the flow sensor
The maximum pressure drop △p of the flow sensor should not exceed 25kPa. 6 General technical requirements
The shell of the heat meter should be evenly coated, without surface defects such as cracks and burrs. The shell should be waterproof and dust-proof, and the direction of the heat-carrying liquid flow should be marked with an arrow.
6.2 The heat meter should have a nameplate, which should indicate the factory name or registered trademark, caliber, model and number, [M mark, 9 measurement range, β measurement range, AG measurement range, maximum allowable working pressure, accuracy level, environmental level, manufacturing year and month, installation location (pipeline inlet or outlet), horizontal installation or vertical installation (if necessary). Note: The environmental level is
A-level environment (indoor installation)
The ambient temperature is (+5～+55): normal humidity; normal electrical and electromagnetic conditions.
B-level environment (outdoor installation):
Ambient temperature is (25～+55)C; normal humidity; 6.3
Usual electrical and electromagnetic environment.
Among the heat energy meters submitted for inspection, the newly manufactured heat energy meters shall have product certificates and instruction manuals; the heat energy meters in use and after repair shall have product certificates, instruction manuals and certificates of last calibration. 6.4 Display requirements for heat energy meters
6.4.1 The heat energy meter shall at least be able to display heat, cumulative flow, heat-carrying liquid inlet temperature and outlet temperature. The display unit of heat shall be J or W·h or its decimal multiple. The display unit of cumulative flow shall be m. The display unit of temperature shall be. The display unit shall be marked in a place where it is not easy to confuse.
6.4.2 The heat energy meter shall display heat without exceeding the range for 3000 hours at the maximum heat power, and the minimum digit of heat display shall step by at least one digit when working for 1 hour at the maximum heat power. 6.4.3 The visible height of the displayed digits shall not be less than 4mm. 6.4.4 Display resolution
Display resolution during use
Heat: 1kW·h or 1MJ; cumulative flow: 0.01m; temperature: 0.1℃.
Display resolution during calibration
For DN15 and DN20 heat meters, heat: generally 0.001kW·h or 0.001MJ; cumulative flow: generally 0.00001m; temperature: 0.1C.
1—10—6
1Heat meters that do not meet the above requirements shall be designed with interfaces and equipped with wiring. During calibration, the resolution can be improved to the above requirements. For heat meters of other calibers, the display resolution of heat and cumulative flow shall meet the requirements of calibration resolution. 6.4.5
The heat meter should enter normal operation after running smoothly for a few minutes after passing the heat-carrying liquid. When the heat-carrying liquid does not flow, the heat display value should remain unchanged.
The removable parts that affect the measurement of the heat meter should have a reliable seal. The seal must be effective.
Material and structure of the heat meter
All parts that constitute the heat meter should have a solid structure. Under the specified temperature conditions, the materials of the heat meter in contact with the heat-carrying liquid should have corresponding mechanical strength and sufficient wear resistance and can work normally. In the heat meter, the materials of all parts in contact with the heat-carrying liquid should be resistant to corrosion by the heat-carrying liquid and the atmosphere or have a reliable anti-corrosion layer. Measuring instrument control
Measuring instrument control includes initial verification, subsequent verification, in-use inspection, finalization and identification, and prototype testing. Appendix A specifies the items and test methods of finalization and identification and prototype testing. 7.1 Verification conditions
7.1.1 Main verification equipment
The main verification equipment is listed in Table 3, and the temperature field requirements of the thermostatic bath are listed in Table 4.
Component verification
General verification
Hot water flow
Standard device
Pressure test equipment
Second-class standard platinum
Resistance thermometer
Flow sensor paired temperature sensor
Hot water flow
Standard device
Pressure test equipment
Second-class standard platinum
Resistance thermometer
Calculator
Signal generator
Standard resistance box
4℃
Measurement rangeWorking area maximum temperature difference
Horizontal temperature field in working area
Constant temperature water tank
Constant temperature oil tank90～200
The expanded uncertainty of the hot water flow standard (coverage factor is 2) should be less than or equal to 1/3 of the maximum allowable error of the heat meter, and the expanded uncertainty of the standard resistance box (coverage factor is 2) should be less than or equal to 1/5 of the maximum allowable error of the heat meter. The standard heat meter can also be used as the standard, and the expanded uncertainty of the standard heat meter (benefit factor is 2) should be less than or equal to 1/3 of the maximum allowable error of the heat meter. The standard heat meter should be calibrated on the hot water device. For standard instruments based on other principles, if their uncertainty can meet the requirements, they can also be used.
The heat standard should have the function of measuring pressure loss. 7.1.4 Environmental and external requirements
Atmospheric temperature is generally (15~35)℃;
Atmospheric relative humidity is generally (15~85)%; Atmospheric pressure is generally (86~106) kPa; Power supply: Power supply voltage is (187~242)V; Power supply frequency is (50±1) Hz;
External magnetic field interference should be small enough to have negligible impact on the heat meter.
The heat meter to be tested should be stored in the laboratory for no less than 2h before the experiment. 7.1.5
7.2 Verification items
The verification items of the heat meter are listed in Table 5.
Verification Items
Appearance Inspection
Operation Inspection
Sealing Inspection
Indication Error
Repeatability
Verification Category
First VerificationSubsequent VerificationIn-use Inspection
Indicates that verification is required; "
7.3 Verification Method
Total Verification Method
Indicates that verification is not required.
Heat meters verified by total quantity shall be verified in at least the following three cases. In each case, select the following: A temperature difference and flow point within a certain range and calibrate at a water temperature of (50±5)C. 1) 8min1.28min0.99q
2) 10≤8≤20 and 0.29≤g≤0.229,3) (0max-5)≤8≤0mx and q,≤q≤1.1g7.3.2 Component calibration method
7.3.2.1 Flow sensor
When calibrating the flow sensor, a flow point should be selected in each of the following flow ranges and calibrated at a water temperature of (50±5)C. 1) q≤q≤1.14;
2) 0.1g,≤q≤0.11g,
3) 0.9g,≤q≤1.0g,
If a type approval certificate and a test report that can explain the comparative performance of the flow sensor at room temperature and (50±5) are provided, the calibration can be carried out at room temperature.
7.3.2.2 Paired temperature sensor
Each temperature sensor of the paired temperature sensor should be calibrated in the same constant temperature bath at one temperature point in each of the following temperature ranges.
1)min～(min+10℃) (when 8min<20℃) or (35～45) (When min≥20)
2) (45～55)℃ (normal temperature type) or (75～85) (high temperature type)
3) (8max-5C)～8mx
Two temperature sensors of the paired temperature sensor should be calibrated at one temperature difference point in each of the following temperature difference ranges in two thermostatic baths with different temperatures.
1)min91.20min
2)10℃≤4020℃
3) (40max -5C) ≤40≤46max
1 When doing temperature difference test, the high temperature end temperature should be within the range of (8mx-5℃)~2max.
2 A0 min- is generally 3C.
7.3.2.3 Calculator
The calculator must be calibrated under the simulated temperature and temperature difference given in Table 6.
Table 6
min08min+5
8g= 8m ±5
mx - 5≤0,≤0mx
40min, 5, 20, 48e
A min，5,20
20, 40ref, A0max -5
9. is the outlet temperature; 6. is the inlet temperature. Grer =
Omin + Omax
Ae rer =
2The analog flow signal should not exceed the maximum value that the calculator can accept. 7.3.3 Calculation formula:
Heat relative error E, and E. Calculation formula: Qai= Gei × 100%
Where: Qdi, Qet
EQ= Eimax
represent the indicated value and the agreed true value of the first point, respectively. Repeatability E, calculation formula:
Va - Vei
×100%
Where Va and Vi
represent the indicated value and the agreed true value of the volume of the flow sensor at the flow rate of 9. The jth (j=1, 2, 3) calibration, respectively.
Emax = Ejmax
Emin = Ejmin
E, = Emax - Emin
7.3.4 Appearance inspection
Use visual inspection to inspect the appearance of the heat meter and check whether the relevant information is complete. Its structure shall comply with the provisions of Article 6. 7.3.5 Operation inspection
Install the heat meter on the heat standard device, and inspect it visually after passing water for a few minutes; then cut off the water flow and inspect it visually again. The result shall comply with the relevant provisions of Article 6.4.
7.3.6 Sealing test
Install the heat meter on the heat standard device, and pass hot water with a temperature of (601 -10-- 7
土10)C for more than 5 minutes. At the same time, adjust the pressure to the nominal pressure of the device, then close the water outlet valve, and inspect it visually after 10 minutes. The result shall comply with the relevant requirements of Article 5.1. 7.3.7 Total volume calibration of heat energy meter
7.3.7.1 During calibration, the temperature of the heat-carrying liquid, the temperature difference between the inlet and outlet, and the flow point shall comply with the requirements of 7.3.1.
7.3.7.2 The number of calibrations is generally 1. If the first E is greater than the maximum allowable error, 2 more tests are allowed, but the E of the next 2 tests should not exceed the maximum allowable error. The arithmetic mean of the 3 tests is used as the indication of the heat energy meter.
7.3.7.3 When a mass method flow standard device is selected, the heat energy meter shall be installed on the mass method heat standard device, and water shall be passed to allow it to run in a balanced manner for a period of time.
Use the flow control valve to adjust the flow base to the i-th point, and adjust the temperature of the heat-carrying liquid to the calibration temperature value. Through the constant temperature bath, adjust the temperature difference to the specified value, stabilize for 10 minutes, weigh out moi, ml; record the readings of the heat meter Qoi, Q1i, water temperature and room temperature. 7.3.7.5 The actual heat Qc and the heat meter display heat Qd are calculated according to formula (9) and formula (10) respectively.
Qei = (m: - moi)× (hi:- ho:)(9)
Wherein: hii, ho-represent the specific melting value of the heat-carrying liquid at the temperature of the high-temperature thermostatic bath and the specific baking value at the set low-temperature thermostatic bath temperature.
Qdi - Q1- Qor
Calculation.
The indication error E of the heat meter at the i-th calibration point: Repeat 7.3.7.4 to 7.3.7.6 according to formula (3), adjust the flow rate and temperature difference to other points, and complete the entire calibration. The indication error E of the heat meter is calculated according to formula (4), and its 7.3.7.8
result should meet the requirements of 5.2.
7.3.8 Component calibration of heat meter (taking mass method flow standard device as an example)
Flow sensor
1) During calibration, the water temperature and flow point shall be in accordance with the provisions of 7.3.2.1. 2) Each flow point is generally calibrated once. If the first E is greater than the maximum allowable error, it is allowed to be re-calibrated twice, but the E of the next two tests should not exceed the maximum allowable error. The arithmetic mean of the three tests is used as the indication of the flow sensor.
3) Install the flow sensor on the device and let water flow to make it run in a balanced manner for a period of time.
4) Use the flow control valve to adjust the flow to the first flow point and adjust the water temperature to the calibration temperature range. Run it stably for 10 minutes, record the initial value Vo of the flow sensor and the initial value moii of the scale, start the commutator, switch the water flow, and let the water flow into the weighing container. When the indication of the scale reaches the predetermined value, switch the water flow, record the end value Vii of the flow sensor, the water temperature Ti; and the room temperature, and after the water surface fluctuation in the container stabilizes, record the end value m1i of the scale.
5) Calculate the volume Ve flowing through the flow sensor: 1—10—8
M; = myi - moi
pr(pb pa)
pb(p: - pa)
the mass of the heat-carrying liquid at the calibration point, kg; where M.
p:—-density of the heat-carrying liquid at the calibration point i, kg/m2 (can be checked in the table);
buoyancy correction coefficient at the calibration point i; density of the magnetic code used, kg/m2;
2.——air density, kg/m.
(6) The indication error of the flow sensor at each flow point is calculated according to formula (14).
Vai - Ve
×100%
Vae = Vhi - Voi
7) Repeat step 4) and adjust the flow until all flow points are calibrated.
8) The indication error of the flow sensor is calculated according to formula (16), and the result should meet the requirements of 5.2.
Ev =Eimax
9) The indication repeatability of the flow sensor is calculated according to formula (5) to (8), and the result should meet the requirements of 5.4. 7.3.8.2 Temperature sensor
1) The calibration point is selected according to the requirements of 7.3.2.2. 2) During the calibration, the temperature sensor should be inserted into the working area of the constant temperature water tank or oil tank, with an immersion depth of 300mm and stabilized for 15 minutes. The temperature change in the water tank or oil tank before and after the calibration should not exceed 0.1C. 3) The calibration of a single sensor is carried out in the same constant temperature, and the temperature of the constant temperature bath is controlled at the calibration point temperature. Each point is read at least two cycles, and each reading cycle is: standard platinum resistance overflow meter → sensor 1 → sensor 2- → standard platinum resistance thermometer; the calibration of the overflow difference of paired temperature sensors is carried out in two constant temperature baths, and the temperature is controlled according to the requirements of the temperature difference calibration point. Each temperature difference point is read at least two processes, and each reading process is: standard platinum resistance thermometer 1- → sensor 1 → standard platinum resistance thermometer 2 → sensor 2. 4) Error calculation method: For the calibration of a single temperature sensor, the difference between the arithmetic mean of the temperature displayed by the sensor under test and the arithmetic mean of the corresponding temperature value of the standard is taken as the error of the sensor; for the calibration of the temperature difference of paired temperature sensors, the difference between the arithmetic mean of the difference between the two displayed temperatures of the sensor under test and the arithmetic mean of the two corresponding temperature differences of the standard is taken as the error of the temperature difference of the paired temperature sensors. 5) The errors of single temperature sensors and paired temperature sensors should meet the requirements of Table 2.
7.3.8.3 Calculator
Use standard pulse generator and standard resistance box to provide simulated flow and temperature signals. The calibration points are set according to Table 6, and each calibration point is calibrated at least twice. The calculated indication error E is calculated according to formula (3) and formula (4), where Q. is the theoretical calculated value. The calibration result shall meet the requirements of E. in Table 2 of 5.2.2.
7.3.9 Repeatability calibration
7.3.9.1 Flow point selection and measurement times
Select 9, flow point, and repeat the measurement 3 times at (50±5)℃. 7.3.9.2 Calculate its repeatability E, according to formula (8). 7.4 Handling of verification results
For heat meters that meet the requirements of this regulation after verification, a verification certificate shall be issued; for heat meters that fail to meet the requirements, a verification result notice shall be issued, and the unqualified items shall be noted
7.5 Verification cycle
The verification cycle of heat meters shall generally not exceed 3 years. Appendix A Type Appraisal and Prototype Test
In addition to the tests required for the initial verification (see Article 7.2 of the main text of the regulations), the items specified in this appendix shall also be tested for the type appraisal items.
A.1 Test items
All the test items involved in this appendix are listed in Table A.1. Test procedure for heat meters and their components
Test items
Indication error
Durability
Dry heat test
Low temperature storage
Low temperature test
Wet heat storage
Temperature sensorFlow sensor
Change in power supply voltage
Change in power supply frequency
Power interruption
Electrical fast transient
Electrical surge
Electromagnetic field
Electrical static discharge
Static magnetic field
Power frequency electromagnetic field
Withstand voltage
Pressure loss test
The test should be carried out;
Only for flow sensors with electronic equipment; Table A.1
Calculator
The test should be carried out with the cable connected. The indication error
should be tested at room temperature, (50±5), (85±5)℃ and specified flow rate. The flow point selection should be in accordance with the following requirements:q;≤ q≤1.1qi
0.1gq0.11p
0.39p≤q≤0.31qm
0.94,≤q≤1.0qp
0.94.≤q≤1.0q
After the heat test, low temperature storage and wet heat storage test are all completed, the indication error test should be spot checked. The spot check test should be carried out at (50±5)℃ and at least two of the following flow points. 0.1qp0.1qp
0.9g,≤g≤1.0qp
A,3 Durability test
The durability of the heat meter is determined by an accelerated wear test. Flow sensor
When the flow rate is 9s and the temperature is at the upper limit of the heat-carrying fluid that the flow sensor needs to withstand, the test duration should be 300h. After the durability test, the indication error test should be carried out at (50±5)°C and the flow rate specified in 7.3.2.1 of the main text of the specification. The result should meet the requirements of 5.2 of the main text of the specification (if max<50℃, it should be carried out within the temperature range of (max-5℃) to max). A.3.2
Temperature sensor
The temperature sensor should be slowly (1min to 3min) inserted into the test device that has reached the upper limit temperature and kept at this temperature for a sufficient time to achieve thermal equilibrium. Slowly (1min to 3min) remove from the test device at the upper limit temperature, leave it at room temperature for a period of time, and then slowly (1min to 3min) insert into the test device that has reached the lower limit temperature and keep it at this temperature for a sufficient time to achieve thermal equilibrium. Finally, slowly (1min to 3min) remove from the test device at the lower limit temperature. This process should be repeated 10 times. After the temperature cycle, the resistance of the temperature sensor as a component should be tested under the following conditions. The insulation resistance between the sensor metal shell and each conductor connected to the sensor should be tested under reference conditions, using a test voltage not exceeding DC 100V. The polarity of the voltage should be reversed. The measured resistance should not be less than 100M. The measurement should be made when the sensor is at the highest temperature. The resistance between the metal shell of the sensor and each conductor connected to the sensor, the test voltage should not exceed DC 10V. The polarity of the voltage should be reversed. The measured resistance should never be less than 10Mn.
Dry heat test
Refer to GB2423.2-1989 "Basic Environmental Test for Electrical and Electronic Products: High Temperature".
Temperature (55±2)C; time 2h; during heating and cooling, the rate of temperature change should not exceed 1℃/min; the relative humidity of the test atmosphere should not exceed 20%.
After the dry heat test, the appearance of the heat meter or its components should not change significantly.
After heating to (55±2)C and reaching temperature stability, the calculator should be tested for indication error. The test conditions are as follows: the simulated outlet temperature is min and ef;
The simulated flow rate should not exceed the maximum value that the calculator can accept; 110—9
The simulated temperature difference is A0min and A0 ref
The test results should meet the requirements of EG in Table 2 of Article 5.2.2 of the main text of the regulations.
Low-temperature storage
Refer to GB2423.1-1989 "Basic Environmental Test for Electrical and Electronic Products: Low Temperature".
Grade A environment: temperature
(～15±3)℃, time 2h
Grade 13 environment: temperature (～30±3)℃, time 2hAfter the low temperature storage test, the appearance of the heat meter or its components shall not change significantly.
A.6 Low temperature test
Grade A environment: temperature (-5±3), time 2hGrade B environment: temperature (-25±3)C, time 2hDuring the cooling and heating process, the temperature change rate shall not exceed 1℃/min.
After cooling to the predetermined temperature and reaching temperature stability, the indication error test of the calculator shall be carried out. The test conditions are as follows: the simulated outlet temperature is 8min and 9rer; the simulated flow rate shall not exceed the maximum value that the calculator can accept; the simulated temperature difference is 48min and Amf
The test results shall meet the requirements of EG in Table 2 of Article 5.2.2 of the main text of the regulations.
Damp heat cycle
Refer to GB/T2423.4-1993 "Basic environmental test for electric and electronic products: alternating damp heat".
Damp heat cycle
Environmental level
Lower limit of temperature/C
Upper limit of temperature C
Relative humidity
Cycle cycle
Number of cycles
≥93%
12h+12h
≥93%
12h+12h
After the damp heat cycle test, the appearance of the heat meter or its components should not change significantly.
A.8 Power supply voltage change
The AC-powered heat meter or its components should be able to work in positive mode under the power supply voltage of 187~242V.
A.9 Power frequency change
The AC powered heat meter or its components shall be able to work normally under the power frequency of 47.552.5Hz.
A.10 Power interruption
This clause is only applicable to heat meters powered by the power grid. Refer to GB/T 17626.11-1998 "Electromagnetic compatibility test and measurement technology" for implementation.
The interruption time shall not be less than 50ms, and the time interval between two consecutive interruptions shall be (10±1)S. The voltage interruption shall be repeated 10 times. The heat meter shall be able to work normally in the power interruption test. 1—10-10
Electrical fast transient (pulse train)
Refer to GB/T17626.4—1998 "Electromagnetic compatibility test and measurement technology" for implementation.
For signal lines and DC power lines, the test voltage is (1±10%)×1.0kV. If the length of the signal line or DC power line is less than 1.2m, this test can be exempted.
For AC power line, the test voltage is (1 10%) × 2.0kv
The heat meter can still work normally after the electrical fast transient test. Electrical surge
Refer to GB/T 17626.5-1998 "Electromagnetic compatibility test and measurement technology".
For signal line and DC power line, the test voltage is 0.5kV. If the length of the signal line or DC power line is less than 10m, this test can be exempted.
For AC power line:
Test voltage (common mode): (1±10%) × 2.0kVTest voltage (differential mode): (1±10%) × 1.0kVThe heat meter should be able to work normally after the electrical surge test. A.13 Electromagnetic field
Frequency range: 26MHz～1000MHz; 3V/mThe heat meter should be able to work normally in the electromagnetic field test. A.14 Electrostatic discharge
Follow GB/T17626.2-1998 Electromagnetic compatibility test and measurement technology.
Discharge voltage: 8kV for air discharge or 4kV for contact discharge. The heat meter should be able to work normally after the electrostatic discharge test. A.15 Static magnetic field
During the test, a permanent magnet with an electromagnetic force of 100kA/m should be in contact with the flow sensor, the outer light of the calculator and the reading device of the heat meter at several locations. On the outer shell of the heat meter, at the position where the static magnetic field will affect the normal operation of the heat meter, it should be marked whether the test has been done, the error, the type of heat meter, the structure and (or) important historical records. Regardless of where the magnet is placed, the indication of the heat meter can be read. The duration of the test should be long enough to determine the error of the heat meter.
The heat meter should be able to work normally in the static magnetic field test. A.16 Power frequency electromagnetic field
Refer to GB/T 17626.8-1998 "Electromagnetic compatibility test and measurement technology".
Magnetic field intensity 60A/m.
The heat meter should be able to work normally in the power frequency electromagnetic field test. A.17 Pressure resistance
The flow sensor should withstand one of the following two conditions without leakage or damage:
(1) Start the test at a water temperature (10±5)°C lower than the upper temperature limit, and the water pressure is 1.6MPa or 1.6 times the maximum working pressure; (2) At a temperature 5°C higher than the upper temperature limit, the water pressure is equal to the maximum working pressure.
The duration of the test should be 15 minutes
A.18 Pressure loss test
When the flow rate is and the temperature is (50±5), the maximum pressure drop Ab should not exceed 25kFao
3 Flame value and density table of waterwww.bzxz.net
Appendix B
When = 0.60000MPa, the stew value and density of water are shown in Table B.1. Table B.1
Temperature indicative
Density/(kg*m2）
Give/(kJ·kg-1）
Temperature indicative
Density/(kgm-13）
Hot/(kj·kg-1)
1—10--11
110—12
Density/(kg2m=13)
Flame (ky·kg2l)
Temperature/C
Density/(kgm~13)
Melting/(kj-kg-)
When pressure = 1.60000MPa, the flame value and density of water are shown in Table B.2. Table B.2
Density/(kg~m23）
/(kJ-kg-1)6 Low temperature test
A-level environment: temperature (-5±3), time 2hB-level environment: temperature (-25±3)C, time 2hDuring the cooling and heating process, the temperature change rate should not exceed 1℃/min.
After cooling to the predetermined temperature and reaching temperature stability, the calculator should be tested for indication error. The test conditions are as follows: the simulated outlet temperature is 8min and 9rer; the simulated flow rate should not exceed the maximum value that the calculator can accept; the simulated temperature difference is 48min and Amf
The test results should meet the requirements of EG in Table 2 of Article 5.2.2 of the main text of the regulations.
Heat cycle
Refer to GB/T2423.4-1993 "Basic environmental test for electrical and electronic products: alternating damp heat" for implementation.
Wet heat cycle
Environmental level
Temperature lower limit/C
Temperature upper limit C
Relative humidity
Cycle cycle
Number of cycles
≥93%
12h+12h
≥93%
12h+12h
After the wet heat cycle test, the appearance of the heat meter or its components shall not change significantly.
A.8 Power supply voltage change
The heat meter or its components powered by AC power shall be able to work in positive mode under the condition of power supply voltage of 187~242V.
A.9 Power supply frequency change
The heat meter or its components powered by AC power shall be able to work normally under the condition of power supply frequency of 47.552.5Hz.
A.10 Power interruption
This clause is only applicable to heat meters powered by the power grid. Refer to GB/T 17626.11-1998 "Electromagnetic Compatibility Test and Measurement Technology".
The interruption time shall not be less than 50ms, and the time interval between two consecutive interruptions shall be (10±1)S. The voltage interruption shall be repeated 10 times. The heat meter shall be able to work normally during the power interruption test. 1-10-10
Electrical fast transient (pulse train)
Refer to GB/T17626.4-1998 "Electromagnetic Compatibility Test and Measurement Technology".
For signal lines and DC power lines, the test voltage is (1 10%) × 1.0kV. If the length of the signal line or DC power line is less than 1.2m, this test can be exempted.
For AC power lines, the test voltage is (1 10%) × 2.0kv
The heat meter can still work normally after the electrical fast transient test. Electric surge
Refer to GB/T 17626.5-1998 "Electromagnetic compatibility test and measurement technology".
For signal line and DC power line, the test voltage is 0.5kV. If the length of the signal line or DC power line is less than 10m, this test can be exempted.
For AC power line:
Test voltage (common mode): (1±10%)×2.0kVTest voltage (differential mode): (1±10%)×1.0kVThermal energy meter should be able to work normally after the electric surge test. A.13 Electromagnetic field
Refer to GB/T17626.3--1998 "Electromagnetic compatibility test and measurement technology".
Frequency range: 26MHz～1000MHz; 3V/mThermal energy meter should be able to work normally in the electromagnetic field test. A.14 Electrostatic discharge
Reference GB/T17626.2-1998 "Electromagnetic compatibility test and measurement technology" for implementation.
Discharge voltage: 8kV for air discharge or 4kV for contact discharge. The heat meter should be able to operate normally after the electrostatic discharge test. A.15 Static magnetic field
During the test, a permanent magnet with an electromagnetic force of 100kA/m should be in contact with the flow sensor, the calculator and the heat meter reading device at several locations. On the heat meter housing, at the location where the static magnetic field may affect the normal operation of the heat meter, it should be marked whether the test has been done, the error, the heat meter type, structure and (or) important historical records. Regardless of the magnet being placed in any of the above positions, the heat meter indication can be read. The test duration should be long enough to allow the error of the heat meter to be determined.
The heat meter should be able to operate normally in the static magnetic field test. A.16 Power frequency electromagnetic field
Refer to GB/T 17626.8-1998 "Electromagnetic compatibility test and measurement technology".
Magnetic field strength 60A/m.
The heat meter should be able to work normally in the power frequency electromagnetic field test. A.17 Compressive strength
The flow sensor should withstand one of the following two conditions without leakage or damage:
(1) Start the test at a water temperature (10±5)°C lower than the upper temperature limit, and the water pressure is 1.6MPa or 1.6 times the maximum working pressure; (2) At a temperature 5°C higher than the upper temperature limit, the water pressure is equal to the maximum working pressure.
The duration of the test should be 15 minutes
A.18 Pressure loss test
When the flow rate is and the temperature is (50±5), the maximum pressure drop Ab should not exceed 25kFao
3 Flame value and density table of water
Appendix B
When = 0.60000MPa, the stew value and density of water are shown in Table B.1. Table B.1
Temperature indicative
Density/(kg*m2）
Give/(kJ·kg-1）
Temperature indicative
Density/(kgm-13）
Hot/(kj·kg-1)
1—10--11
110—12
Density/(kg2m=13)
Flame (ky·kg2l)
Temperature/C
Density/(kgm~13)
Melting/(kj-kg-)
When pressure = 1.60000MPa, the flame value and density of water are shown in Table B.2. Table B.2
Density/(kg~m23）
/(kJ-kg-1)6 Low temperature test
A-level environment: temperature (-5±3), time 2hB-level environment: temperature (-25±3)C, time 2hDuring the cooling and heating process, the temperature change rate should not exceed 1℃/min.
After cooling to the predetermined temperature and reaching temperature stability, the calculator should be tested for indication error. The test conditions are as follows: the simulated outlet temperature is 8min and 9rer; the simulated flow rate should not exceed the maximum value that the calculator can accept; the simulated temperature difference is 48min and Amf
The test results should meet the requirements of EG in Table 2 of Article 5.2.2 of the main text of the regulations.
Heat cycle
Refer to GB/T2423.4-1993 "Basic environmental test for electrical and electronic products: alternating damp heat" for implementation.
Wet heat cycle
Environmental level
Temperature lower limit/C
Temperature upper limit C
Relative humidity
Cycle cycle
Number of cycles
≥93%
12h+12h
≥93%
12h+12h
After the wet heat cycle test, the appearance of the heat meter or its components shall not change significantly.
A.8 Power supply voltage change
The heat meter or its components powered by AC power shall be able to work in positive mode under the condition of power supply voltage of 187~242V.
A.9 Power supply frequency change
The heat meter or its components powered by AC power shall be able to work normally under the condition of power supply frequency of 47.552.5Hz.
A.10 Power interruption
This clause is only applicable to heat meters powered by the power grid. Refer to GB/T 17626.11-1998 "Electromagnetic Compatibility Test and Measurement Technology".
The interruption time shall not be less than 50ms, and the time interval between two consecutive interruptions shall be (10±1)S. The voltage interruption shall be repeated 10 times. The heat meter shall be able to work normally during the power interruption test. 1-10-10
Electrical fast transient (pulse train)
Refer to GB/T17626.4-1998 "Electromagnetic Compatibility Test and Measurement Technology".
For signal lines and DC power lines, the test voltage is (1 10%) × 1.0kV. If the length of the signal line or DC power line is less than 1.2m, this test can be exempted.
For AC power lines, the test voltage is (1 10%) × 2.0kv
The heat meter can still work normally after the electrical fast transient test. Electric surge
Refer to GB/T 17626.5-1998 "Electromagnetic compatibility test and measurement technology".
For signal line and DC power line, the test voltage is 0.5kV. If the length of the signal line or DC power line is less than 10m, this test can be exempted.
For AC power line:
Test voltage (common mode): (1±10%)×2.0kVTest voltage (differential mode): (1±10%)×1.0kVThermal energy meter should be able to work normally after the electric surge test. A.13 Electromagnetic field
Refer to GB/T17626.3--1998 "Electromagnetic compatibility test and measurement technology".
Frequency range: 26MHz～1000MHz; 3V/mThermal energy meter should be able to work normally in the electromagnetic field test. A.14 Electrostatic discharge
Reference GB/T17626.2-1998 "Electromagnetic compatibility test and measurement technology" for implementation.
Discharge voltage: 8kV for air discharge or 4kV for contact discharge. The heat meter should be able to operate normally after the electrostatic discharge test. A.15 Static magnetic field
During the test, a permanent magnet with an electromagnetic force of 100kA/m should be in contact with the flow sensor, the calculator and the heat meter reading device at several locations. On the heat meter housing, at the location where the static magnetic field may affect the normal operation of the heat meter, it should be marked whether the test has been done, the error, the heat meter type, structure and (or) important historical records. Regardless of the magnet being placed in any of the above positions, the heat meter indication can be read. The test duration should be long enough to allow the error of the heat meter to be determined.
The heat meter should be able to operate normally in the static magnetic field test. A.16 Power frequency electromagnetic field
Refer to GB/T 17626.8-1998 "Electromagnetic compatibility test and measurement technology".
Magnetic field strength 60A/m.
The heat meter should be able to work normally in the power frequency electromagnetic field test. A.17 Compressive strength
The flow sensor should withstand one of the following two conditions without leakage or damage:
(1) Start the test at a water temperature (10±5)°C lower than the upper temperature limit, and the water pressure is 1.6MPa or 1.6 times the maximum working pressure; (2) At a temperature 5°C higher than the upper temperature limit, the water pressure is equal to the maximum working pressure.
The duration of the test should be 15 minutes
A.18 Pressure loss test
When the flow rate is and the temperature is (50±5), the maximum pressure drop Ab should not exceed 25kFao
3 Flame value and density table of water
Appendix B
When = 0.60000MPa, the stew value and density of water are shown in Table B.1. Table B.1
Temperature indicative
Density/(kg*m2）
Give/(kJ·kg-1）
Temperature indicative
Density/(kgm-13）
Hot/(kj·kg-1)
1—10--11
110—12
Density/(kg2m=13)
Flame (ky·kg2l)
Temperature/C
Density/(kgm~13)
Melting/(kj-kg-)
When pressure = 1.60000MPa, the flame value and density of water are shown in Table B.2. Table B.2
Density/(kg~m23）
/(kJ-kg-1)3--1998 "Electromagnetic Compatibility Test and Measurement Technology".
Frequency range: 26MHz～1000MHz; 3V/mThe heat meter should be able to work normally in the electromagnetic field test. A.14 Electrostatic discharge
Refer to GB/T17626.2-1998 "Electromagnetic Compatibility Test and Measurement Technology".
Discharge voltage: 8kV for air discharge or 4kV for contact discharge. The heat meter should be able to work normally after the electrostatic discharge test. A.15 Static magnetic field
During the test, a permanent magnet with an electromagnetic force of 100kA/m should be in contact with the flow sensor, the calculator and the heat meter reading device at several locations. On the outer shell of the heat meter, at the position where the static magnetic field will affect the normal operation of the heat meter, it should be marked whether the test has been done, the error, the heat meter type, the structure and (or) important historical records. Regardless of the magnet placed in any of the above positions, the heat meter indication can be read. The duration of the test should be long enough to allow the error of the heat meter to be determined.
The heat meter should be able to operate normally in the static magnetic field test. A.16 Power frequency electromagnetic field
Refer to GB/T 17626.8-1998 "Electromagnetic compatibility test and measurement technology".
Magnetic field strength 60A/m.
The heat meter should be able to operate normally in the power frequency electromagnetic field test. A.17 Pressure resistance
The flow sensor should withstand one of the following two conditions without leakage or damage:
(1) Start the test at a water temperature (10±5)°C lower than the upper temperature limit, and the water pressure is 1.6MPa or 1.6 times the maximum working pressure; (2) At a temperature 5°C higher than the upper temperature limit, the water pressure is equal to the maximum working pressure.
The duration of the test should be 15 minutes
A.18 Pressure loss test
When the flow rate is and the temperature is (50±5), the maximum pressure drop Ab should not exceed 25kFao
3 Flame value and density table of water
Appendix B
When = 0.60000MPa, the stew value and density of water are shown in Table B.1. Table B.1
Temperature indicative
Density/(kg*m2）
Give/(kJ·kg-1）
Temperature indicative
Density/(kgm-13）
Hot/(kj·kg-1)
1—10--11
110—12
Density/(kg2m=13)
Flame (ky·kg2l)
Temperature/C
Density/(kgm~13)
Melting/(kj-kg-)
When pressure = 1.60000MPa, the flame value and density of water are shown in Table B.2. Table B.2
Density/(kg~m23）
/(kJ-kg-1)3--1998 "Electromagnetic Compatibility Test and Measurement Technology".
Frequency range: 26MHz～1000MHz; 3V/mThe heat meter should be able to work normally in the electromagnetic field test. A.14 Electrostatic discharge
Refer to GB/T17626.2-1998 "Electromagnetic Compatibility Test and Measurement Technology".
Discharge voltage: 8kV for air discharge or 4kV for contact discharge. The heat meter should be able to work normally after the electrostatic discharge test. A.15 Static magnetic field
During the test, a permanent magnet with an electromagnetic force of 100kA/m should be in contact with the flow sensor, the calculator and the heat meter reading device at several locations. On the outer shell of the heat meter, at the position where the static magnetic field will affect the normal operation of the heat meter, it should be marked whether the test has been done, the error, the heat meter type, the structure and (or) important historical records. Regardless of the magnet placed in any of the above positions, the heat meter indication can be read. The duration of the test should be long enough to allow the error of the heat meter to be determined.
The heat meter should be able to operate normally in the static magnetic field test. A.16 Power frequency electromagnetic field
Refer to GB/T 17626.8-1998 "Electromagnetic compatibility test and measurement technology".
Magnetic field strength 60A/m.
The heat meter should be able to operate normally in the power frequency electromagnetic field test. A.17 Pressure resistance
The flow sensor should withstand one of the following two conditions without leakage or damage:
(1) Start the test at a water temperature (10±5)°C lower than the upper temperature limit, and the water pressure is 1.6MPa or 1.6 times the maximum working pressure; (2) At a temperature 5°C higher than the upper temperature limit, the water pressure is equal to the maximum working pressure.
The duration of the test should be 15 minutes
A.18 Pressure loss test
When the flow rate is and the temperature is (50±5), the maximum pressure drop Ab should not exceed 25kFao
3 Flame value and density table of water
Appendix B
When = 0.60000MPa, the stew value and density of water are shown in Table B.1. Table B.1
Temperature indicative
Density/(kg*m2）
Give/(kJ·kg-1）
Temperature indicative
Density/(kgm-13）
Hot/(kj·kg-1)
1—10--11
110—12
Density/(kg2m=13)
Flame (ky·kg2l)
Temperature/C
Density/(kgm~13)
Melting/(kj-kg-)
When pressure = 1.60000MPa, the flame value and density of water are shown in Table B.2. Table B.2
Density/(kg~m23）
/(kJ-kg-1)
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