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Industry standard of black and white video intercom system

August 21, 2023

Industry standard of black and white video intercom system

Foreword This standard provides technical requirements and experimental methods for the most basic one-to-one black and white Video Intercom System for Video Intercom products. Color video Intercom System and networked video intercom system can be used for reference.

Audio and video indicators are important technical performance of the video intercom system. On the basis of analyzing and summarizing the detection situation of the Louyu intercom system and black and white camera products, this standard puts forward the technical requirements and test methods of audio indicators based on the principle of practicality and reliability.

This standard was proposed by the Science and Technology Bureau of the Ministry of Public Security of the People's Republic of China.
This standard is under the jurisdiction of the National Technical Committee for Standardization of Security and Alarm Systems.
This standard was drafted by: Ministry of Public Security Safety and Police Electronic Product Quality Testing Center, Shenzhen Bailan Industrial Development Co., Ltd., Dongguan Weijun Electronics Co., Ltd.
The main drafters of this standard: Liu Jianfeng, Che Hongku, Zhang Dayong, Chen Jincheng.
This standard was first published in January 2001.
Public Safety Industry Standard of the People's Republic of China GA / T 269-2001
Black-white video doorphone system

1 Scope

This standard specifies the system composition, technical requirements, product classification, experimental methods, inspection rules and signs, packaging, transportation, and storage of black-and-white video intercom systems. It is the basic basis for the design, manufacture, and acceptance of black-and-white video intercom products.

This standard is applicable to the black and white video intercom system (hereinafter referred to as the system) for wired transmission.

2 Quote

Standards The provisions contained in the following standards constitute the provisions of this standard by quotation in this standard. At the time of publication, the editions indicated were valid. All standards will be revised, all parties using this standard should explore the possibility of using the latest version of the following standards.

GB-191-2000 Graphic symbol for packaging, storage and transportation GB / T 2828-1987 Sampling procedure and sampling table for batch-by-batch inspection (applicable to continuous batch inspection)
GB / T 2828-1987 Periodic inspection counting sampling procedure and sampling table (applicable to the inspection of the stability of the production process)
GB 4208-1993 enclosure protection level (IP code)
GB / T 12338-1990 Black and white general-purpose application TV camera measurement method GB / T 15211-1994 alarm system environmental test GB / T 16796-1997 safety precaution alarm equipment safety requirements and experimental methods GB / T 17626.2-1998 electromagnetic compatibility test and measurement Technology Electrostatic Discharge Immunity Test GB / T 17626.3-1998 Electromagnetic Compatibility Test and Measurement Technology RF Electromagnetic Field Radiation Immunity Test GB / T 17626.4-1998 Electromagnetic Compatibility Test and Measurement Technology Electrical Fast Transient Pulse Group Immunity Test GB / T 17626.4-1998 T 17626.11-1999 Electromagnetic compatibility test and measurement technology Voltage sag, short interruption and voltage change immunity test


3 Definitions This standard adopts the following definitions 3.1 video doorphone system
Intercom system showing real-time images of visitors 3.2 main unit
The video intercom system is installed at the entrance of the building with the functions of strobe, camera and intercom.
3.3 Extension auxiliary unit
The video intercom system is installed in the user room with functions such as image display and intercom.
3.4 Video channel
The image captured by the host is transmitted to the channel of the extension monitor.
3.5 calling channel
The channel from the input end of the host to the output end of the extension.

4 The composition of the system The video intercom system is composed of a host, extensions, transmission lines and other parts.

5 Technical requirements 5.1 Operating environment conditions Ambient temperature: Group I: -10 ~ + 55 ℃
Ⅱ: -25 ~ + 70 ℃
Ⅲ: -40 ~ + 70 ℃]
Relative humidity: 10% ~ 95%
Atmospheric pressure: 86 ~ 106KPa

5.2 Appearance and structural requirements 5.2.1 The external dimensions of the main unit, extensions and Accessories should meet the requirements of product drawings.
5.2.2 The surface of the plastic shell should be smooth and smooth, without cracks, discoloration and permanent stains, and no obvious deformation and scratches.
5.2.3 The surface coating of the metal shell cannot expose the underlying metal, and there is no blistering, corrosion, nicks, burrs, pits, scratches, coating shedding and sand holes.
5.2.4 The operation of keys and switches is flexible and reliable, and the parts should be fastened without looseness.
5.2.5 After fixed installation, the terminals and jacks of the main unit and extensions should not be exposed on the touchable surface.
5.2.6 The terminal should have measures to prevent rotation and loosening. After 20 connections and 20 disconnection tests on the quick-connect terminal, apply a pulling force of 24.5N for 60s in the direction that is most easily broken. None of the columns should fall off.
5.2.7 Protection ability of the host casing

The protection ability of the main body shell is divided into two levels.
a) Level 1;
Comply with the provisions of IP33 in GB4208-1993. The enclosure should be able to withstand the 49N pressure test, and no permanent deformation or damage should be produced after the test. The shell should be able to withstand the impact strength test of a steel ball with a diameter of 50.8 mm falling freely from a height of 0.5m. After the test, there should be no permanent deformation or damage.

b) Level 2;
Comply with the provisions of IP33 in GB4208-1993. The enclosure should be able to withstand the 111N pressure test, and no permanent deformation or damage should be produced after the test. The outer shell should be able to withstand the impact strength test of a steel ball with a diameter of 50.8 mm falling freely from a height of 1.3m. After the test, no permanent deformation or damage should occur.

5.2.8 The protection capability of the enclosure of the extension is in accordance with the provisions of IP30 in GB4208-1993. The enclosure should be able to withstand the 49N pressure test, and no permanent deformation or damage should be produced after the test.

5.2.9 Anti-dismantling requirements for the shell of the main machine The shell of the main machine shall have protective measures against abnormal removal.

5.3 Basic functional requirements 5.3.1 Call function After the main unit and the extension are connected by a key, the two parties can communicate, the voice quality is clear, and there should be no ringing.
5.3.2 Monitoring function After the main unit and the extension are connected by a key, the image signal taken by the main unit can be viewed on the extension monitor, which is convenient for identifying the visitor.
5.3.3 Night vision function Under normal installation, the host can identify visitors on the extension monitor at night.
5.3.4 Anti-vandalism alarm function The visual intercom system shall have an anti-vandalism alarm output interface. When the host encounters abnormal disassembly, the extension should immediately give an alarm.
5.4 Main electrical performance index 5.4.1 Audio index 5.4.1.1 The audio response of the calling channel and answer channel is in the range of 500 ~ 3000Hz, and the amplitude change relative to 1000Hz should be within ± 3dB.
5.4.1.2 Under the condition that the audio output power of the calling channel and answer channel is 50mW, the harmonic distortion of the calling channel and answer channel should be no more than 5%.
5.4.1.3 Signal-to-noise ratio a) The signal-to-noise ratio of the response channel should not be less than 25dB;
b) The signal-to-noise ratio of the calling channel should not be less than 40 dB;
5.4.1.4 Channel input signal voltage a) The response channel input signal voltage should not exceed 40mV;
b) The input signal voltage of the calling channel should not exceed 30m V.
5.4.1.5 The ringing pressure should not be less than 70 dB (A).

5.4.2 Video index 5.4.2.1 The minimum illuminance of the system camera should not be greater than 0.1Lx.
5.4.2.2 The minimum illumination of the system camera should not be less than 4500 Lx.
5.4.2.3 The image brightness discrimination level on the system monitor is not less than 8.
5.4.2.4 The image resolution (center level) on the system monitor is not less than 320TVL.
5.4.3 Static power consumption

Static power consumption should meet the requirements of enterprise product standards.
5.5 Range of power supply voltage AC: 220V + 22-33vv
Or DC: 12V + 1.2? 1.8vv
The system should meet the requirements of 5.3 within the specified power supply voltage variation range.

5.6 Lighting or instruction requirements The host should provide lighting or instructions so that visitors can operate at night.

5.7 Safety requirements 5.7.1 Insulation requirements 5.7.1.1 Insulation resistance The insulation resistance between the power plug or power inlet terminal and the shell or bare metal parts of the shell should not be less than 100 MΩ under normal environmental conditions, and not less than 5 MΩ under humid and hot conditions .
5.7.1.2 Electric strength a) For systems with AC 220V power supply, the power plug or power inlet terminal and the shell or bare metal parts of the shell should be able to withstand an AC effective value of 1.5kV test voltage for 1min of electric strength test, There shall be no breakdown or arcing during the test.
b) For the system with DC 12V power supply, the power plug or power inlet terminal and the shell or the exposed metal parts of the surgery should be able to withstand the test voltage of 0.5kV effective voltage for 1min, and there should be no breakdown during the test And flashover.
5.7.2 Overcurrent protection 5.7.2.1 If there are short-circuiters or fuses in the primary circuit of the transformer, their rating should be compatible with the maximum input rating of the product.
5.7.2.2 For terminals that do not require polarity discrimination, short-circuit or reverse connection in pairs with adjacent terminals, or touch the power supply terminal, neither the product nor the internal circuit should be damaged.
For terminals that require polarity discrimination, the polarity sign should be kept closest to the terminal.
5.7.3 Flame retardant requirements For products with open holes in the casing and a fire hazard, the casing should be burned 5 times with flames for 5 seconds each time.
5.7.4 Ignition due to human faults Products without overload protection should not have the risk of electric shock or burning when they cause the most severe circuit faults.
5.7.5 Overvoltage operation requirements The product should be able to work normally when the power supply voltage is 115% of the rated value.

5.8 Environmental adaptability requirements 5.8.1 According to the severity of its environment, it is divided into three groups:
Group Ⅰ: It can withstand occasional light vibrations, can adapt to moderate high and low temperature and humidity changes, and is used under general indoor conditions.
Group Ⅱ: It can withstand a sudden drop or withstand a large degree of vibration and shock during frequent movement, and can adapt to a wide range of high and low temperature and humidity changes.
Group Ⅲ: In addition to the conditions of Group Ⅱ, it has been used under severe cold weather.
5.8.2 Climate and environment adaptability requirements The products are tested according to the conditions specified in Table 1. After each test, they should be able to work normally.

5.9 Anti-interference requirements 5.9.1 The system is tested under the conditions of the contact discharge test level 4 specified in GB / T 17626.2, which meets the requirements of 5.3.1 and 53.2.
5.9.2 The system is tested under the condition of the test level 1 of GB / T 17626.3, which meets the requirements of 5.3.1 and 5.3.2.
5.9.3 The system powered by AC 220V is tested under the test level 1 specified in GB / T 17626.4, which meets the requirements of 5.3.1 and 5.3.2.
5.9.4 The system powered by AC 220V is tested under the conditions of 40% Ut, 10 cycles of voltage sag and 0% Ut, 10 cycles of short-term interruption specified in GB / T 17626.11, which meets 5.3.1 And the requirements of 5.3.2.
5.10 Stability requirements The video intercom system should work continuously for 7 days under normal climatic conditions. There should be no failures, and the sound quality of the call is clear, and the image signal is stable.
5.11 Reliability requirements Under normal operating conditions, the mean time between failures (MTBF) should not be less than 5000h.

6 Product classification According to the protection ability of the system shell and the severity of the use environment, the products are divided into A, B, C and D four grades.

7 Test methods 7.1 Test conditions 7.1.1 Unless otherwise specified, all tests shall be conducted under the following normal atmospheric conditions:
Temperature: 15 ~ 35 ℃
Relative humidity: 45% ~ 75%
Atmospheric pressure: 86 ~ 106Kpa
7.1.2 Power supply voltage: AC 220V ± 4.4V
AC 12V ± 0.1V
7.1.3 The test of electrical performance should generally be carried out under the combination of the basic unit (including one main unit and one extension, and the transmission line connecting the main unit and the extension is 10m long).
7.1.4 The measurement of electrical performance parameters is that the microphone cannot be connected.
7.2 Appearance and structure inspection 7.2.1 Appearance inspection a) Check the product dimensions with calipers and other measuring tools against the drawings, visually inspect the appearance, and inspect the control mechanism by hand, all should meet the requirements of 5.2.1 ~ 5.2.5;
b) The test sample is fixed in the normal position, the lead wire is connected according to the product manual, and the tensile force is gradually applied to the sample along the lead wire to the value specified in 5.2.6, maintaining 60s ± 2s, and the lead wire and terminal are checked after the test The test results should meet the requirements of 5.2.6.

7.2.2 Enclosure protection capability test a) The tested samples are tested for enclosure protection level according to the test method specified in GB4208, and the test results should meet the requirements of 5.2.7 and 5.2.8;
b) The test sample shall be subjected to the shell pressure test and impact strength test according to the test method specified in GB / T15211. The test results shall meet the requirements of 5.2.7 and 5.2.8;
c) When the receiving sample machine is in the waiting state, the shell of the host machine is abnormally disassembled, and there should be an alarm prompt.

7.3 Basic function check The basic function test method adopts the actual operation on site to check the functions of each control mechanism and the functions of call and monitoring. The inspection results should meet the requirements of 5.3.
7.4 Main electrical performance test 7.4.1 Audio index test 7.4.1.1 Audio response test The output power at the output end of the call is the rated output power (50mW). Then gradually increase the frequency of the input signal from 500Hz to 3000Hz (keep the input voltage unchanged), and measure the change of its output amplitude relative to the amplitude at 1000Hz, expressed in dB. The test result should meet the requirements of 5.4.1.1. The test schematic is shown in Figure 1.

b) Audio response test of the calling channel Input a 1000Hz sine wave signal at the output of the host microphone, adjust the amplitude of the input signal, so that the output rated output power (5mW) of the extension receiver output. Then gradually increase the frequency of the input signal from 500 Hz to 3000 Hz (keep the input voltage unchanged), and measure the change in the output amplitude relative to the amplitude at 1000 Hz, expressed in dB. The test result should meet the requirements of 5.4.1.1.

Input a 1000Hz sine wave signal at the output of the extension microphone, adjust the amplitude of the input signal to make the output power of the host's receiving output be the rated output power (50mW), and measure the distortion of its output voltage with a distortion meter. Adjust the signal generator to 500 Hz and 3000 Hz, and repeat the above test. The test results shall meet the requirements of 5.4.1.2. The test schematic is shown in Figure 1.

B) Harmonic distortion test of the main call channel Input a 1000Hz sine wave signal at the output of the host fax machine to adjust the amplitude of the input signal so that the output power of the extension's receiving output is the rated output power (5mW). Use a distortion meter Measure the distortion of its output voltage. . Adjust the signal generator to 500 Hz and 3000 Hz, and repeat the above test. The test results shall meet the requirements of 5.4.1.2.

7.4.1.3 Signal-to-noise ratio test a) Answer-channel signal-to-noise ratio test Input 1000Hz sine wave signal at the output of the extension microphone, adjust the amplitude of the input signal, so that the output power of the host's receiver output is the rated output power (50mW ), Then remove the input signal, connect the output terminal of the extension microphone in parallel with a well-shielded resistor (the resistance value is the same as the output impedance of the signal generator), use a millivolt meter to measure the noise voltage at the output terminal of the host, and calculate the signal voltage The difference between the decibel and the noise voltage shall be in accordance with the requirements of 5.4.1.3.a.

B) The signal-to-noise ratio test of the main call channel: input a 1000Hz sine wave signal at the output of the host microphone, adjust the amplitude of the input signal to make the output power of the host's receiving output be the rated output power (5mW), and then remove the input signal , Connect the output end of the extension microphone in parallel with a well-shielded resistor (the resistance value is the same as the output impedance of the signal generator), use a millivolt meter to measure the noise voltage at the output end of the extension receiver, and calculate the decibel of the signal voltage and the noise voltage Difference, the result should meet the requirements of 5.4.1.3.b.

7.4.1.4 Channel input signal voltage test Input a 1000Hz sine wave signal at the output of the extension microphone, adjust the amplitude of the input signal to make the output power of the host's receiver output at the rated output power (50mW), measured with a millivolt meter The voltage of its input signal. Adjust the signal generator to 500 Hz and 3000 Hz, and repeat the above test. The test result shall meet the requirements of 5.4.1.2a.

Input a 1000Hz sine wave signal at the output end of the host microphone, adjust the amplitude of the input signal to make the output power of the host's receiving output end be the rated output power (50mW), and measure the voltage of the input signal with a millivoltmeter. Adjust the signal generator to 500 Hz and 3000 Hz, and repeat the above test. The test results shall meet the requirements of 5.4.1.2b.

7.4.1.5 Ringing pressure test When ringing, in an environment with an ambient noise of not more than 60dB (A), use a sound level meter to measure 500mm directly in front of the center axis of the speaker.
7.4.2 Video index test 7.4.2.1 Minimum illuminance test The tested samples are subjected to the minimum illuminance test according to the method specified in 5.3 of GB / T12338-1990. The test results shall meet the requirements of 5.3.3 and 5.4.2.1.
7.4.2.2 Maximum illuminance test The tested samples are tested for maximum illuminance according to the method specified in 5.3 of GB / T12338-1990. The test results shall meet the requirements of 5.3.2 and 5.4.2.2.
5.4.2.3 Brightness discrimination level test The tested samples shall be tested for the extension monitor brightness discrimination level according to the method specified in 5.3 of GB / T12338-1990. The test results shall meet the requirements of 5.4.2.3.
7.4.2.4 Resolution test The tested samples shall be subjected to the extension monitor resolution test according to the method specified in 5.3 of GB / T12338-1990. The experimental results should meet the requirements of 5.4.2.4.4.
7.4.3 Static power consumption test When the system is in the waiting state, measure the system power consumption with a power meter at the power supply end. The measurement result shall meet the requirements of 5.4.3.
7.5 Power supply voltage adaptability range test Adjust the power supply voltage of the tested sample to 85% of the rated value and 110% of the rated value, and check the basic functions of the system according to the method of 7.3. The test results should meet the requirements of 5.5.
7.6 Illumination or indication function experiment Use actual operation and visual methods to check whether the host has illumination or indication function. The result should meet the requirements of 5.6.
7.7 Safety test 7.7.1 Insulation performance test 7.7.1.1 Insulation resistance test According to the provisions of 4.4.4 in GB16796-1997, the test results shall meet the requirements of 5.7.1.1 of this standard.
7.7.1.2 Electric strength test According to the provisions of 4.4.3 in GB16796-1997, the test results shall meet the requirements of 5.7.1.2 of this standard.
7.7.2 Overcurrent protection test According to the provisions of 4.4.9 and 4.4.11 in GB16796-1997, the test results shall meet the requirements of 5.7.2 of this standard.
7.7.3 Flame retardant test According to the provisions of 4.6.2 in GB16796-1997, the test results should meet the requirements of 5.7.3 of this standard.
7.7.4 Ignition test for man-made faults According to the provisions of 4.4.11 in GB16796-1997, the test results shall meet the requirements of 5.7.4 of this standard.
7.7.5 Overvoltage operation test Adjust the power supply voltage to 115% of the rated value, and take 10s ringing, 30s monitoring and talking as one working cycle, and 50 working cycles. The test results shall meet the requirements of 5.7.5.
7.8 Environmental adaptability test After the following environmental tests, all shall meet the requirements of 5.8.
7.8.11 Climate and environment adaptability test a) The low temperature test shall be carried out according to the conditions and methods specified in Table 1 and 5.2 in GB / T15211-1994;
b) The high temperature test is carried out according to the conditions and methods specified in Table 1 and 5.1 in GB / T15211-1994;
c) The constant damp heat test is carried out according to the conditions and methods specified in Table 1 and 5.6 in GB / T15211-1994;
7.8.2 Mechanical environment adaptability test a) Vibration test is carried out according to the conditions and methods specified in Table 2 and 5.4 in GB / T15211-1994;
b) The impact test is performed according to the conditions and methods specified in Table 2 and 5.3 of GB / T15211-1994;
c) The free drop test is carried out according to the conditions and methods specified in Table 2 and 5.12 in GB / T15211-1994;
7.9 Anti-interference test 7.9.1 Electrostatic discharge anti-interference test The tested sample shall be tested according to the method specified in GB / T17626.2, and the test result shall meet the requirements of 5.9.1.
7.9.2 Radio frequency electromagnetic field radiation immunity test The tested sample is tested according to the method specified in GB / T17626.3, and the test result should meet the requirements of 5.9.2.
7.9.3 Electrical fast transient pulse group immunity test The tested sample is tested according to the method specified in GB / T17626.4, and the test result should meet the requirements of 5.9.3.
7.9.4 Immunity test for voltage sag, short-term interruption and voltage change The tested sample is tested according to the method specified in GB / T17626.11, and the test result should meet the requirements of 5.9.4.
7.10 Stability test The samples that have been initially tested shall work continuously for 7 days under normal environmental conditions, and at least three basic functional tests shall be carried out each day. The test results shall meet the requirements of 5.10.

8 Inspection rules 8.1 Inspection classification Product inspection sub-identification inspection and quality consistency inspection.
8.1.1 Appraisal inspection Appraisal inspection should be carried out during design and production finalization. Appraisal inspection should be carried out after the main design, process, materials and components (parts) are replaced or production is resumed after shutdown.
8.1.2 Quality consistency inspection Group A inspection (batch-by-batch): full inspection (small batch) when the product is delivered.
Group B inspection (batch by batch): when the products are delivered, sampling inspection.
Group C inspection (period): It is conducted every six months, and the tested samples are randomly selected from the acceptance inspection batches.
Group D inspection (period): annually.

8.2 Test items The test items, test methods, technical requirements and unqualified classification of various inspections shall be as specified in Table 4.

8.3 Group batch and sampling rules 8.3.1 Group batch rules The group batch for inspection shall consist of products of the same production batch.
8.3.2 Sampling rules 8.3.2.1 The test samples for identification and inspection are 3 sets (3 mainframes, 3 extensions).
8.3.2.2 Quality consistency inspection Group A inspection is full inspection. The samples of Group B inspection are randomly selected from the qualified batch of Group A inspection by the quantity specified in GB / T2828.
The samples of Group C and Group D are randomly selected from the qualified batches of A and B inspection according to the quantity specified in GB / T2829.

8.4 Judgment rules 8.4.1 Determine whether the sample is qualified according to the test items, technical requirements, test methods and unqualified classification specified in Table 4, if there is an item that does not meet the requirements, it is judged as unqualified product.
All samples tested should be qualified. If the number of unqualified samples is less than or equal to the number of qualified judgments, the batch is qualified; if the number of unqualified is equal to or greater than the number of unqualified judgments, the batch is rejected.
8.4.2 Unless otherwise specified, GB / T 2828-1987 inspection level II is generally adopted. In Group B inspection, the qualified quality level (AQL) of Class B non-conforming product is 1.5, and the qualified quality level (AQL) of Class C non-conforming product is 4. The qualified quality level (RQL) of qualified products is 20, and the qualified quality level (RQL) of unqualified products is 25.
8.4.3 Strictness adjustment of sampling plan In the batch-by-batch inspection of continuous batches, if the quality level remains good or poor, the relaxation or tightening inspection should be carried out according to the transfer rules stipulated in GB / T2828.

8.5 Disposal of non-conforming product 8.5.1 The non-conforming product in the qualified batch shall be replaced or repaired by the factory to a qualified product.
8.5.2 When the inspection of Group B, Group C or Group D fails, the representative batch of products should stop the inspection, analyze the reasons, eliminate the unqualified factors and then submit the inspection.
8.6 Resubmission of batches If the batch inspection fails, after repair, commissioning, and inspection are passed, the specified number of samples are randomly selected again for inspection.
If it is still unqualified, it can be rejected. After checking the reasons and taking measures to pass the new cycle test, the normal production and delivery test can be resumed.

9 Signs, packaging, transportation and storage

9.1 Marks 9.1.1 Marks should be clear, not misunderstood, and not easy to erase.
9.1.2 The product should be marked:
a) Manufacturer's name (or registered trademark), address, and maintenance phone number;
b) Product name or model;
c) The nature of the power supply: the symbol for communication is "~"; the symbol for DC is "-" or "=";
d) Rated power supply voltage or voltage range;
e) Product grade.
9.2 Packaging 9.2.1 Individual 9.2.2 Choose suitable packaging box according to product size. The packing box shall have the signs of "Handle with care", "Moisture-proof" and the name of the manufacturer, product model and name, quantity, date of manufacture and weight, etc. in accordance with GB191.
9.3 Transportation and storage 9.3.1 The packaged product should have the product manual (including circuit diagram, printed circuit diagram and assembly wiring diagram), certificate of conformity, warranty card and other accessories in the box. It should be able to withstand the transportation of cars, trains, ships and airplanes.
9.3.2 During transportation, attention shall be paid to protection from rain, dust and mechanical damage.
9.3.3 The packaged products should be stored in ambient temperature I-10 ~ + 40, relative humidity not more than 80%, no corrosive gas, well ventilated indoor or warehouse.

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