Brushless miniature D.C. blower,General specification for
Some standard content:
Military Standard of the Electronic Industry of the People's Republic of China FL5990
SJ20039—92
General specification for small brushless DC blower
Published on February 1, 1992
Approved by China Electronics Industry Corporation
Implementation on May 1, 1992
1 Scope
1.1 Subject Content Military Standard of the Electronic Industry of the People's Republic of China General Specification for Small Brushless DC Blower
Brushless miniature DC, blower,General specificationfor
SJ20039--92
This specification specifies the classification, general technical requirements, quality assurance regulations, and requirements for marking, packaging, transportation and storage of small brushless DC fans (hereinafter referred to as fans) with a blade diameter not exceeding 300mm. 1.2 Scope of Application
This specification applies to fans used as cooling devices in radar, communication and other military electronic equipment. Brushless DC fans with a blade diameter greater than 300mm can also refer to this specification. Other requirements and special requirements not specified in this specification shall be specified in the relevant detailed specifications (hereinafter referred to as detailed specifications). 1.3 Classification
1.3.1 Voltage Level
The rated voltage of the fan shall be selected from the following values: 4.5, 6, 12, 24, (28), 36, 48, 60V. 1.3.2 Model naming
The model of the fan consists of the following parts
1.3.2.1 Fan number
Derived code
Bearing type code
Performance parameter code
Product name code
Fan number
Military symbol
The fan number is expressed in millimeters of the fan blade diameter. 1.3.2.2 Product name code
The product name code is expressed by 34 uppercase Chinese phonetic letters, as shown in Table 1. China Electronics Industry Corporation issued on February 1, 1992 and implemented on May 1, 1992
Product name
Simple axial flow fan without drama DC network
Shaving DC propeller axial flow fan
Brushless DC centrifugal fan
1.3.2.3 Performance parameter code
SJ20039—92
Wind, shaft, no
Wind, shaft, propeller, no
Wind, centrifugal, no
The performance parameter code of axial flow fan is represented by 4 to 5 Arabic numerals, with a short stroke between the second and third Arabic numerals. The first Arabic numeral represents the voltage level, and its code is shown in Table 2: The second Arabic numeral represents the speed. Its code is shown in Table 3: The third and fourth Arabic numerals indicate the axial length and millimeter of the fan Table 2 Voltage level code
Voltage level code
Rated voltage V
Speed code
Nominal speed
Table 3 Speed code
The performance parameter code of the centrifugal fan is specified by the detailed specifications, 1.3.2.4 Bearing type code
"G" indicates a ball bearing structure fan, and "H" indicates an oil-containing bearing structure fan. 1.3.2.5 Derived code
Derivation includes structural derivation and performance derivation. The derived code is represented by the Chinese phonetic letters "A" "B"..., but the letters I and O shall not be used. The specific meaning and use of the letters are specified in the detailed specifications. 1.3.2.6 Example
J100FZW33-38G indicates a basic military brushless DC cylindrical axial fan with a fan blade diameter of 100mm, a rated voltage of 12V, a nominal speed of 3000~3999r/min, an axial length of 38mm, and a ball bearing structure. 1.4 Lead-out wires and terminals
1.4.1 The fan lead-out wires can be lead-out wires, lugs or threaded terminals. 1.4.2 Lead-out wire marking
The lead-out wires are red and black wires, and their length should not be less than 200mm. The red wire is connected to the positive pole of the power supply, and the black wire is connected to the negative pole of the power supply.
When using lugs or threaded terminals, there should be obvious "+" and "+" marks on the terminals. 2 Reference documents
GB2658--87
GB10069.1—88
General technical conditions for small AC fans
Determination method and limit of noise of rotating electrical machines
Noise engineering determination method
GJB179—86
GJB271-87
GJB360—87
GJB361—87
|3 Requirements
3.1 Detailed Specifications
SJ20039—-92
Counting Sampling Inspection Procedure and Table
Control Micromotor Packaging
Test Methods for Electronic and Electrical Components
Basic Technical Requirements for Control Micromotor
The requirements for each fan shall comply with the provisions of this specification and the relevant detailed specifications. If there is a conflict between the requirements of this specification and the requirements of the detailed specifications, the latter shall prevail. 3.2 Qualification Appraisal
The products submitted in accordance with this specification shall be products that have been qualified or approved for finalization. 3.3 Materials
The materials used in the fan structure shall comply with the requirements of its specifications and shall ensure that the fan can meet the performance and environmental requirements specified in this specification.
3.4 Environmental Conditions for Use
3.4.1 The environmental conditions for the use of the fan shall be selected as specified in Table 4. Table 4
Environmental conditions
-55~125
Relative humidity
7412.5mmHg
14850m
15mmHg
26600m
31200m
10~55Hz
Double amplitude 1.5mm
10~500Hz
Low double amplitude
Peak acceleration
70m/s2
10~2 000Hz
Low frequency double amplitude
Peak acceleration
70m/s2
Impact acceleration peak
3.4.2 Under special circumstances, the temperature of various fan operating environment conditions can be selected from the following number systems: low temperature: -10, -25, 40, -55, -65℃; high temperature: 40, 5570, 85, 100, 125155.3.5 Appearance
The fan surface should not have rust, coating peeling, bumps, scratches, and fasteners should be firmly connected. The handwriting and content of the terminal board and nameplate should be clear and correct, and should not fall off. The lead wires and wiring belts should be intact and the color and markings should be correct. -3
3.6 Appearance and installation dimensions
SJ20039--92
The appearance and installation dimensions of the fan shall comply with the provisions of the detailed specifications. 3.7 Weight
The weight of the fan shall comply with the provisions of the detailed specifications. 3.8 Strength of lead terminals and wiring terminals
The fan lead terminals shall be able to withstand the lead terminal strength test specified in Article 2.3 of GJB361. After the test, the lead terminals shall not be loose or damaged, the lead wires shall not be broken, and the insulation layer shall not be permanently deformed. 3.9 Reference speed and direction
The reference speed (the stable speed measured before the wrinkle test) and direction of the fan shall comply with the provisions of the detailed specifications. The nominal speed specified in the detailed specifications is approximately equal to the reference speed. 3.10 Subsequent speed
The subsequent speed (the speed measured according to the provisions of this specification after measuring the reference speed) shall not be less than 95% of the reference speed specified in Article 3.9. However, the subsequent speed after the low temperature test shall not be less than 80%. 3.11 Working current
The working current of the fan shall comply with the provisions of the detailed specifications. 3.12 Starting current
The starting current of the fan shall comply with the provisions of the detailed specifications. 3.13 Low voltage starting
The fan shall be able to start and operate continuously at 75% of the rated voltage. 3.14 Aging
The fan shall be able to withstand the aging test under the extreme high temperature environment specified in the detailed specifications. After the test, the subsequent speed and working current shall comply with the provisions of Articles 3.10 and 3.11.
3.15 Power supply polarity branch protection
The fan shall be able to withstand the power supply polarity reverse connection protection test. After the test, the fan can operate normally at the rated voltage, and its subsequent speed and working current shall comply with the provisions of Articles 3.10 and 3.11. 3.16 Power supply voltage change
When the fan operates at 90% to 110% of the rated voltage, the fan shall operate continuously without failure. 3.17 Self-vibration
The effective value of the self-vibration force of the fan shall comply with the provisions of the detailed specifications. After the life test, its increase value shall not exceed 25% of the initial value.
3.18 Dynamic balance
The effective value of the dynamic balance of the fan shall comply with the provisions of the detailed specifications. 3.19 Dielectric withstand voltage
The fan shall be able to withstand the dielectric withstand voltage test of 500V DC voltage. There shall be no insulation breakdown or arcing during the test. The leakage current shall be less than 500uA.
3.20 Insulation resistance
The insulation resistance of the fan winding to the casing shall not be less than 12MQ. 3.21 Airflow characteristics
The air volume of the fan at zero static pressure and static pressure specified in the detailed specifications shall comply with the provisions of the detailed specifications. 3.22 Temperature rise
SJ20039-92
The temperature rise of the fan winding shall comply with the provisions of the detailed specifications. 3.23 Electromagnetic Interference
When required by the detailed specifications of the fan, the electromagnetic interference of the fan shall comply with the provisions of Article 2.20 of GJB361. 3.24 Noise
The sound power level noise of the fan shall comply with the provisions of the detailed specifications. 3.25 Low Temperature
The fan shall be able to withstand the low temperature test under the extreme low temperature of the environment specified in Table 4 or the detailed specifications. During the test, the fan shall be able to start, and its subsequent speed shall not be less than 80% of the reference speed, and the operating current shall comply with the provisions of Article 3.11. 3.26 Low Pressure
3.26.1 Low Temperature and Low Pressure
The fan shall be able to withstand the test under the low temperature (or as specified in the detailed specifications) and low pressure specified in Table 4. During the test, the fan shall be able to start, and its subsequent speed shall not be less than 80% of the reference speed, and the operating current shall comply with the provisions of Article 3.11. 3.26.2 High temperature and low pressure
The fan shall be able to withstand the high temperature (or as specified in the detailed specification) and low pressure test specified in Table 4. After the test, the subsequent speed and working current shall comply with the provisions of Articles 3.10 and 3.11. 3.27 Vibration
The fan shall be able to withstand the vibration test of the severity specified in Table 4 or the detailed specification. After the test, the fan shall have no mechanical damage and loose or damaged parts, and the subsequent speed, working current, and self-vibration shall comply with the provisions of Articles 3.10, 3.11, and 3.17. 3.28 Impact
The fan shall be able to withstand the impact test of the severity specified in Table 4 or the detailed specification. After the test, the fan shall have no mechanical damage and loose or damaged parts, and the subsequent speed, working current, and self-vibration shall comply with the provisions of Articles 3.10, 3.11.3.17. 3.29 Constant acceleration
When the detailed specification requires, the fan shall be able to withstand the structural deformation caused by constant acceleration. After the test, the parts shall not be damaged. The subsequent speed, working current and self-vibration shall comply with the provisions of 3.10 and 3.11.3.17. The constant acceleration level should preferably be 196, 490 and 980m/s2. 3.30 Mixed heat
The fan shall be able to withstand the damp heat test with relative humidity specified in Table 4. After the test, the fan shall have no obvious deterioration of appearance quality and rust that affects normal operation. The subsequent speed, working current, insulation dielectric strength and insulation resistance shall comply with the provisions of 3.10, 3.11.3.19 and 3.20.
3.31 Salt spray
When required by the detailed specification of the fan, the fan shall be able to withstand the specified salt spray test. After the test, no obvious rust shall occur on any part of the fan, and the speed, operating current, dielectric strength and insulation resistance shall meet the requirements of 3.10, 3.11, 3.19 and 3.20.
3.32 High temperature life
The fan shall be able to undergo a 1000h life test at the extreme ambient high temperature specified in the detailed specification. After the test, the speed, operating current and self-vibration shall meet the requirements of 3.10, 3.11 and 3.17. 4 Quality assurance provisions
4.1 Inspection responsibility
Unless otherwise specified in the contract or order, the contractor shall be responsible for completing all inspections specified in this specification. If necessary, the ordering party5
SJ20039-92
or the superior appraisal agency has the right to conduct inspections on any of the inspection items described in the specification. 4.2 Inspection classification
The inspections specified in this specification are divided into identification inspection and quality consistency inspection. 4.3 Inspection conditions
4.3.1 Standard atmospheric conditions
The standard atmospheric conditions during the test shall comply with the provisions of Article 4.1 of GJB360.1. The temperature under the reference standard atmospheric conditions is 20℃.
4.3.2 Test power supply
The ripple voltage of the test power supply shall not be greater than 2% of the rated voltage, and the voltage regulation rate shall be ±2%. 4.3.3 Test equipment
The accuracy of the instruments and equipment used in the test shall not be less than Class 1 for Group A inspection of quality consistency, and shall not be less than Class 0.5 for identification inspection and Group B and C inspection of quality consistency. 4.3.4 Test status
4.3.4.1 Operating status
Except for the airflow characteristic test, other performance tests refer to the fan being carried out in a free state at rated voltage. 4.3.4.2 Preheating
In the identification inspection and the inspection of Group B and Group C for quality consistency, the fan shall be preheated by applying the rated voltage before the speed, current, self-vibration and airflow characteristics tests. The winding temperature is measured once every minute. If the difference between 5 consecutive readings is less than 0.5℃, the fan is considered to have reached thermal equilibrium, that is, the preheating process is completed. Fans with intermittent cycle operation should be preheated according to their normal working cycle. If the time interval between the two tests does not exceed 3h, no preheating is required. 4.4 Identification Inspection
The 6 fan prototypes manufactured according to the detailed specification requirements shall be inspected in Table 5. The satisfactory completion of the identification inspection is the basis for obtaining the identification approval. If there is any non-conformity in the identification inspection, it shall be handled in accordance with the provisions of Article 4.6.1. After the sample is submitted for identification, no changes in materials, design or manufacturing process are allowed without the approval of the superior identification agency. Table 5 Identification test
Test items
Group 1 (6 prototypes)
Appearance and installation dimensions
Lead wire and terminal strength
Reference speed and direction
Working current
Starting current
Low voltage starting
Power supply polarity reverse protection
Requirement clause
Method clause
Test items
Power supply voltage change
Self-vibration
Dielectric withstand voltage
Insulation Resistance
Group II (2 Prototypes)
Airflow Characteristics
Electromagnetic Interference
Low Air Pressure
Constant Acceleration
Group (4 Prototypes)
High Temperature Life
4.4.1 Retention of Qualification
SJ20039—92
Continued Table 5
Requirement Clauses
Method Clauses
In order to maintain the qualification, the Contractor shall submit a report to the superior appraisal agency every 12 months. The superior appraisal agency shall determine the date of the first submission of the report. The contents of the report are as follows: a. A summary of the results of the tests conducted by the Group A and Group B inspections for quality consistency, at least indicating the number of qualified batches and the number of unqualified products, and the retest results of all repaired batches shall be noted and explained. b. A summary of the results of the tests conducted by the Group C inspection for quality consistency, at least indicating the number of unqualified products in each group. The test results summary shall include the test results of all verification tests conducted on completed batches during the 24-month period. If the test results summary indicates that the product does not meet the requirements of the specification and corrective measures agreed to by the superior appraisal agency are not taken, the product may be disqualified from appraisal.
Failure to submit a report within 30 days after the end of the 24-month period may also result in the product being disqualified from appraisal. In addition to submitting inspection data regularly, the contractor shall immediately report to the superior appraisal agency if the inspection data indicates that the product does not meet the requirements of this specification.
4.5 Quality consistency inspection
The quality consistency inspection shall include three groups of inspections, A, B, and C, and the inspection procedures shall be carried out in the order listed in Tables 6, 7, and 9. 4.5.1 Group A inspection
Group A inspection consists of the inspections listed in Table 6. The fans produced in Group A inspection shall be inspected according to the general inspection level in GJB179 and SJ20039-92-1, and the acceptable quality level (AQL) shall be shown in Table 6. Failure of Group A inspection shall be handled in accordance with the provisions of Article 4.6.2.
The inspection batch shall consist of fans of the same design, material, process and produced under basically the same conditions and submitted at the same time. Table 6 Group A inspection
Test items
Overall dimensions
Insulation dimensions
Starting current
Working current
Reference speed and directionwww.bzxz.net
Insulation resistance
Dielectric pressure
Dynamic balance
4.5.2 Group B inspection
Requirement clause
Method clause
Group B inspection consists of the inspections listed in Table 7. Group B inspection shall be conducted by randomly selecting samples from the batch that has passed the Group A inspection. The number of samples submitted for Group B inspection shall be as specified in Table 8. If the inspection fails, it shall be handled in accordance with the provisions of Article 4.6.2. Table 7 Group B inspection
Test items
Low voltage start
Power supply voltage change
Power supply polarity reverse protection
Air flow characteristics
Lead wire and terminal strength
Batch of fan
40 and below
41~110
111~300
301~500
501~800
801~3200
More than 3200
4.5.3 Group C inspection||tt ||Requirement clause
Table 8 Sampling number for Group B inspection
Number of prototypes
Number of qualified judgments
Method clause
Number of unqualified judgments
SJ20039---92
Group C inspection consists of the inspections listed in Table 9. At least two fan prototypes should be selected from the batch that has passed the Group A inspection for Group B inspection. If two prototypes are selected, one will be subjected to Group 1 and Group 1 inspections, and the other will be subjected to Group 2 inspection; if three prototypes are selected, Group 1, Group 1 and Group 2 inspections will be carried out on prototypes respectively. For Group C and Group 1 inspections, they are conducted once every full year, and reorganization inspections are conducted once a year. Delivery according to the contract or order shall not be delayed due to the failure to obtain the results of Group C tests, and fans that have passed Group C inspections shall not be delivered according to the contract or order. If the prototype inspection fails, it shall be handled in accordance with the provisions of Article 4.6.2. The fan shall not be allowed to be delivered before the contractor takes the necessary repair measures and proves to the superior appraisal agency that the measures taken are effective.
Table 9 Group C inspection
Test items
Group 1 (two years)
Low pressure
Constant acceleration
Group 1 (two years)
Reorganization (years)
High temperature life
4.6 Rejection and retest
4.6.1 Appraisal test||tt| |Request Clauses
Method Clauses
Unless otherwise specified, any rejected fan may be repaired or have parts replaced to repair defects, and be resubmitted for inspection. A detailed report on the rejection and measures taken on the original test sample shall be submitted to the superior inspection agency before resubmission for inspection test, and the inspection can only be re-conducted after approval by the superior inspection agency. Fans that have been rejected twice due to the same defect cannot be submitted again without the special approval of the superior inspection agency. 4.6.2 Group A, Group B and Group C Inspection
Rejected fans may be repaired or have parts replaced to repair defects, and then be resubmitted for Group A, Group B and Group C inspection. Before the rejected fan is resubmitted, a detailed report on the failure of the original test and the repair measures taken on the original test sample shall be provided to the superior inspection agency. Report. Fans that have been rejected twice due to the same defect shall not be submitted again without the special approval of the superior appraisal agency. 4.7 Inspection method
4.7.1 Appearance
Visually inspect the fan processing quality, cleanliness and the firmness of all fits, which shall comply with the provisions of Article 3.5. 4.7.2 Appearance and installation dimensions
Use measuring tools that can ensure accuracy to check the appearance and installation dimensions of the fan, which shall comply with the provisions of Article 3.6. 4.7.3 Measurement
Weigh the weight of the fan with a scale with a sensitivity of 1%, which shall comply with the provisions of Article 3.7. 4.7.4 Strength of lead wires and terminals
The fan lead wires and terminals shall be inspected in accordance with the provisions of Test Condition A in Article 3.4 of GJB361, and the tensile force applied to each lead wire or terminal is 10N. ||tt| |SJ20039-92
The fan terminal is inspected according to the provisions of test condition E in GJB360.21. After the test, the strength of the fan lead wire and terminal shall comply with the provisions of Article 3.8. 4.7.5 Reference speed and direction
The fan is applied with rated voltage, and its reference speed is measured with a tachometer with an accuracy of ±2% and the direction of the fan blades is observed. The fan reference speed and direction shall comply with the provisions of Article 3.9. 4.7.6 Working current
The fan is applied with rated voltage, and the working current is measured with a DC ammeter. Its value shall comply with the provisions of Article 3.11. 4.7.7 Starting current
The fan is applied with rated voltage, and tested with a fast-response instrument that can monitor the transient starting current of the DC motor (such as an eight-wire oscilloscope, a slow-scan oscilloscope). The maximum starting current of the fan shall comply with the provisions of Article 3.12. 4.7.8 Low voltage start
When the fan is in a stationary state, apply voltage to 75% of the rated voltage at a rate of 1V/s. The fan should be able to start and run continuously.
4.7.9 Aging
Place the fan in a high temperature box. The box temperature is the maximum high temperature specified in the fan detailed specification, with a temperature difference of ±2°C. The fan is applied with rated voltage and runs continuously for 48 hours. After the test, the fan should comply with the provisions of Article 3.14. 4.7.10 Power supply polarity reverse connection protection
Connect the positive lead or terminal of the fan to the negative pole of the power supply, and the negative lead or terminal to the positive pole of the power supply, and apply rated voltage. After the test, the fan should comply with the provisions of Article 3.15. 4.7.11 Power supply voltage change
Apply 90% and 110% of the rated voltage to the fan, and run for 2 hours each. The fan should comply with the provisions of Article 3.16. 4.7.12 Self-vibration
The method for determining the self-vibration of the fan shall comply with the provisions of Article 3.10 of GB2658, among which "fan installation" shall comply with the provisions of Article 5.1 of GB10069.1. The self-vibration value shall comply with the provisions of Article 3.17. 4.7.13 Dynamic balancing
4.7.13.1 Installation
The fan shall be elastically fixed on the mounting bracket so that the fan can vibrate along all axes. The weight of the bracket shall not exceed 15% of the total weight of the accelerometer connection block and the fan. The displacement caused by the stretching or compression of the elastic support due to the weight of the fan and the bracket shall not be less than the value calculated by the following formula, and the elastic support is allowed to bend. 622×105
Where: 6--minimum stretching or compression displacement, mm: n-nominal speed of the fan, r/min.
4.7.13.2 Test Instruments
A calibrated accelerometer system is used, and its output must be fed through an appropriate filter. The filter should be adjusted to read the vibration at the operating speed of the fan. A low-pass filter can be used to eliminate low-frequency vibrations below the operating speed. The output of the filter should not affect the amplitude of the input signal of the accelerometer system. If the input signal amplitude changes, the measured frequency and voltage values should be corrected. The output of the filter is fed to an effective value voltmeter, which has sufficient damping (not exceeding 10s) to limit accidental or transient amplitude distortion, and the input impedance should not be less than 1M2. 4.7.13.3 Measurement
The accelerometer sensing axis is placed on the plane of the bearing housing end cover perpendicular to the motor rotation axis. If this cannot be installed, the vibration can be measured on the fan end plane or bracket plane perpendicular to the rotation axis. The accelerometer can be equipped with a sharp pointer or screw, and the needle tip is pointed at the fan. The reading of the voltmeter can be calculated using the effective value acceleration in units of effective millivolts, and the dynamic balance effective value is calculated using the following formula. Vrmm=9550a/n
Wherein, Vrms dynamic balance effective value, mm/s; a---effective value acceleration, m/s\;
it fan speed, r/min.
The measured fan dynamic balance effective value shall comply with the provisions of Article 3.17. 4.7.14 Dielectric Withstand Voltage
A DC voltage of 500-2V is applied between the lead wire and the casing of the fan, and the effective value of the DC voltage pulsation component shall not exceed 5%. The test voltage is increased slowly from zero to 500V for not less than 3s, maintained at 500V for 1min, and then slowly reduced to zero for not less than 3s. At the same time, the fan leakage current is measured. This current should not include the capacitive current of the equipment. During the test, the fan should comply with the provisions of Article 3.19.
4.7.15 Insulation resistance
The fan insulation resistance is tested in accordance with the provisions of Article 3.14 of GJB361, using a 500V megohmmeter, and its value should comply with the provisions of Article 3.20.
4.7.16 Airflow characteristics
The fan airflow characteristics are carried out in accordance with the provisions of Article 3.13.1 of GB2658, and its value should comply with the provisions of Article 3.21. 4.7.17 Temperature rise
The fan temperature rise is carried out in accordance with the provisions of Article 3.12.2 of GB2658, and its value should comply with the provisions of Article 322. For fans with intermittent cycle operation, the temperature difference of the motor windings in at least six consecutive working cycles shall not exceed 0.5℃, the fan is considered to have reached a stable temperature rise.
4.7.18 Electromagnetic interference
The electromagnetic interference of the fan shall be tested in accordance with the provisions of Article 3.21 of GJB361, and its value shall comply with the provisions of Article 3.23. 4.7.13 Noise
The fan shall be tested for noise in accordance with the provisions of Article 8.2 of GB10069.1, with a measurement radius of 1m. Its value shall comply with the provisions of Article 3.24. 4.7.20 Low temperature
Put the fan in a low temperature box without power, the box temperature is the extreme low temperature specified in the detailed specification of the fan, the temperature difference is ±3℃, and keep it in the box for 16 hours. Then apply the rated voltage to the fan in this low temperature environment, measure the speed within the initial 5 minutes of applying the rated voltage, and turn off the power after the fan runs continuously for 8 hours. Repeat the above test cycle once. The fan shall comply with the provisions of Article 3.25. 4.7.21 Low pressure
The low temperature low pressure and high temperature low pressure tests of the fan shall be carried out in accordance with the provisions of Article 3.26 of GJB361. However, the low temperature, high temperature and low pressure values shall be in accordance with the provisions of Article 3.26. After the test, the fan shall comply with the provisions of Article 3.26. 4.7.22 Vibration
The vibration test of the fan shall be carried out in accordance with the method specified in GJB360.13. The vibration frequency and acceleration peak value shall be in accordance with Table 4 or the detailed specifications. After the test, it shall comply with the provisions of Article 3.27. 11
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