This standard specifies the product classification, technical requirements, test methods, inspection rules, and marking, packaging, transportation, storage, etc. of manual fat analyzers. This standard applies to manual fat analyzers (hereinafter referred to as "analyzers") for determining the fat percentage of fresh milk and sterilized milk. QB/T 1676-1992 Manual Fat Analyzer QB/T1676-1992 Standard download decompression password: www.bzxz.net

Light Industry Industry Standard of the People's Republic of China
Manual fat analyzer
1 Subject content and scope of application
QB/T 1676---1992
This standard specifies the product classification, technical requirements, test methods, inspection rules, as well as marking, packaging, transportation, storage, etc. of manual fat analyzers.
This standard applies to manual fat analyzers (hereinafter referred to as "analyzers") for determining the fat percentage of fresh milk and sterilized milk. 2 Reference standards
GB/T191 Pictorial markings for packaging, storage and transportation
GB/T998 Basic test methods for low-voltage electrical appliances
GB/T2421 General rules for basic environmental testing procedures for electrical and electronic products GB/T2423.4
Basic environmental testing procedures for electrical and electronic products Test Db: Alternating damp heat test method GB/T5009.46 Analytical methods for hygienic standards for milk and dairy products QB/T18 23 Method for compiling dairy machinery models 3 Product classification
3.1 Model
According to QB/T1823, the model of the measuring instrument is: Y
3.2 Basic parameters
Main parameters (number of samples measured per hour)
-Fat
Measurement and analysis
Dairy instruments
3.2.1 Power supply: AC 220±22V, 50Hz, DC 12V. 3.2.2 Working efficiency: (80~100) milk samples/h. 3.2.3 Milk sample dosage: 0.44mL for each measurement. 3.2.4 Dilution volume: 6.6 mL for each measurement. 4 Technical requirements
4.1 Working conditions
The ambient temperature is 5~40℃, and the relative humidity is ≤85%. 4.2
General requirements
The Ministry of Light Industry of the People's Republic of China approved the quasi-thermal test on January 15, 1993
Implemented on September 1, 1993
QB/T1676-1992
4.2.1 The measuring instrument shall comply with the provisions of this standard and be manufactured according to the drawings and technical documents approved by the prescribed procedures. 4.2.2 The components and devices in the circuit shall comply with the relevant national standards and have a product certificate. 4.2.3 The switch parts shall be flexible and have good contact; the circuit shall be free of defects such as false welding, leaking welding, and tin nodules. 4.2.4 The liquid pipeline part shall be well sealed and leak-free. 4.2.5 The materials of the parts used in contact with the diluent shall meet the requirements of anti-corrosion. 4.3 Technical performance
4.3.1 Self-test display value
The self-test display value is (5.00±0.10)%. 4.3.2 Repeatability
Repeatability standard deviation Si shall meet the following requirements: a.
When the fat content is (1～~5)%, it shall not be greater than 0.03%; when the fat content is (>5～8)%, it shall not be greater than 0.04%; when the fat content is (>8～13)%, it shall not be greater than 0.08%. 4.3.3 Accuracy
Accuracy standard deviation S2 shall meet the following requirements: when the fat content is (1～5)%, it shall not be greater than 0.06% relative to the Gottlieb-Roch method; b.
When the fat content is (>5～8)%, it shall not be greater than 0.10% relative to the Gottlieb-Roch method; when the fat content is (8~～~13)%, it shall not be greater than 0.20% relative to the Gottlieb-Roch method. 4.3.4
Cold insulation resistance should be no less than 20MQ
Withstand 50Hz, 1500V power frequency withstand voltage test for 1min, no breakdown or flashover. b.
4.3.5 Current consumption
When the power supply voltage is 220V, the current consumption is not more than 0.6A. 4.3.6 Transportation and storage requirements
4.3.6.1 In the packaged state, the product shall be tested according to the conditions specified in Table 1 and Table 2, and the product performance shall comply with the provisions of this standard. Table 1 Transport and storage environmental conditions
Test items
High temperature test
Low temperature test
Warm test
High temperature and high humidity
Low temperature and high humidity
Temperature/℃
Test time
40±2℃.8h
—10±2℃, 8h
Test for two cycles according to the conditions specified in Table 2 Table 2 Wet heat test conditions
Relative humidity/(%)
30Rise to 40
40 Drop to 30
Time/h
Put the packaged products on a car and drive 100km at a speed of 20~40km/h on a third-level road. 4. 3. 6.2)
Check that the measuring instrument meets the requirements of this standard. 284
Quasi-thermal network
Standard theft chamber
5 Test method
QB/T 1676---1992
Unless otherwise specified, the test conditions of the measuring instrument shall comply with the provisions of "normal test atmospheric conditions" in Article 4.3 of GB/T2421. 5.2 The accuracy level of the electrical measuring instruments used in the various tests of the measuring instrument shall comply with the provisions of Table 3. Table 3 Accuracy level of instruments used in various tests
5.3 Self-test display value
Instrument name
Megohmmeter
Ammeter
Voltmeter
Other instruments
Factory inspection
Accuracy level (not less than)
Type inspection
Set the "measurement selection" switch to the "self-test" position, and the digital display value should be between (4.9 and 5.1)%. 5.4 Repeatability inspection
Set the "repeat" switch to the "repeat\" position, and take a milk sample in the fat content range of (1~5)%, (>5~～8)%, and (>8～13)%. Each milk sample is measured 10 times on the measuring instrument, and the measurement results are recorded each time. Calculate according to formula (1) Calculate the repeatability standard deviation: (x, —)2
Wherein: Si
repeatability standard deviation;
each measurement value, —1,2,3··10, yuan—arithmetic mean of multiple measurements;
-number of measurements.
The calculation result should meet the requirements of Article 4.3.2.
5.5 Accuracy check
Before performing the accuracy check, it is allowed to calibrate the accuracy and zero the measuring instrument. (1)
5.5.1 Take 10 For milk samples with fat content between (1~5)%, these milk samples should be distributed at intervals according to the fat content. 5.5.2 Determine the fat percentage of each milk sample according to the Terry-Rodriguez method in GB/T5009.46 as the reference value of the fat content of the milk sample.
5.5.3 Set the "repeat" switch to the "repeat" position and the "measurement selection" switch to the "I" or "II" position. Each milk sample is measured three times on the measuring instrument using the normal method, and the average value is taken as the determination result of the fat percentage of the milk sample. 5.5.4 Calculate the accuracy standard deviation according to formula (2): (Ar; - A)2
Where: S-accuracy standard deviation
-the measurement error of the fat content of a single milk sample;
the arithmetic mean of the measurement error of the fat content of the milk sample; the number of milk samples.
The calculation result should meet the requirements of Article 4.3.3a. n-1
5.5.5 Take 10 milk samples with fat content between >(5~~8)%. The fat content of these milk samples should be distributed at intervals. Test and calculate according to the methods of 5.5.2~5.5.4. The results should meet the requirements of 4.3.3b. 285
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QB/T 1676—1992
5.5.6 Take 10 milk samples with fat content between >(8~13)%. The fat content of these milk samples should be distributed at intervals. Test and calculate according to the methods of 5.5.2~5.5.4. The results should meet the requirements of 4.3.3c. 5.6 Insulation inspection
5.6.1 In the cold state, use a 500V megohmmeter to check the insulation resistance between the AC 220V terminal and the housing of the measuring instrument. It should meet the requirements of 4.3.4a.
5.6.2 Perform a power frequency withstand voltage test between the AC 220V terminal and the housing according to the methods required in 6.3.2 and 6.3.3 of GB/T998. The test shall meet the requirements of 4.3.4b. 5.7 Current consumption
When the power supply voltage is 220V, the total current consumption of the measuring instrument shall not exceed 0.6A. 5.8 High and low temperature working condition test
a. The measuring instrument is placed in a high temperature box at 40±2℃ for 2h, and the test is performed according to the method in 5.4. The test shall meet the requirements of 4.3.2; b. The measuring instrument is placed in a high temperature box at 5±2℃ for 2h, and the test is performed according to the method in 5.4. The test shall meet the requirements of 4.3.2. 5.9 Transportation and storage test
All transportation and storage tests of the measuring instrument are carried out in a completely packaged state. 5.9.1 High temperature transportation and storage test
Put the package in a high temperature box, raise the temperature to 40±2℃ at a rate of no more than 10℃/min, keep it for 8h, then let the package cool to room temperature and take it out of the high temperature box. Leave it under normal atmospheric conditions for 24h. Check that the performance of the measuring instrument meets the requirements of 4.3.2a and 4.3.3a.
5.9.2 Low temperature transportation and storage test
Put the package in a low temperature box, lower the temperature to -10±2℃ at a rate of no more than 1℃/min, keep it for 8h, then let the package slowly warm to room temperature and take it out of the low temperature box. Leave it under normal atmospheric conditions for 24h. Check that the performance of the measuring instrument meets the requirements of 4.3.2a and 4.3.3a.
5.9.3 Wet heat test
The test chamber shall comply with the requirements of Chapter 2 of GB/T2423.4. Test the packaged product according to the conditions specified in Table 2 for two cycles, and then place it under normal atmospheric conditions for 24 hours. Check that the performance of the measuring instrument complies with the requirements of Articles 4.3.2a and 4.3.3a. 5.9.4 Transportation test
After the automobile transportation test is carried out according to the requirements of Article 4.3.6.2, check that the performance of the measuring instrument complies with the requirements of Articles 4.3.2a and 4.3.3a. 6 Inspection rules
6.1 Inspection classificationwwW.bzxz.Net
Product inspection is divided into factory inspection and type inspection. 6.2 Factory inspection
Each measuring instrument must undergo factory inspection before leaving the factory. After the product is qualified, the product certificate must be filled out before it can leave the factory. The factory inspection items are as follows:
General requirements inspection,
Self-test display value inspection;
Repeatability inspection [only check the fat content (1～5)% range]; c.
Accuracy inspection [only check the fat content (1～5)% range]; e.
Insulation inspection,
Consumption current inspection.
6.3 Type inspection
6.3.1 The items of type inspection shall be carried out in accordance with all the requirements of Chapter 4. 286
QB/T 1676—1992
After the product is finalized, the type inspection shall be carried out once a year. The sampling quantity shall be 1% of the annual output, but not more than 3 units. 6.3.2
When the product has any of the following conditions, the type inspection shall be carried out. 6.3.3
Trial production and identification of new products or old products transferred to the factory for production; after formal production, if there are major changes in structure, materials, and processes that may affect product performance; when the product is resumed after one year of suspension; when the factory inspection results are significantly different from the last type inspection; when the national quality supervision agency proposes a type inspection requirement. If there are unqualified items in the type inspection, two times the sample should be re-drawn and then the type inspection should be carried out again (double inspection). If the double inspection is qualified, 6.3.4
the type inspection can be considered qualified. If there are unqualified items, the type inspection is considered unqualified. 7 Marking, packaging, transportation, storage
7.1 Marking
7.1.1 Product marking includes:
Manufacturer name;
Product name;
Trademark;
Product model,
Product factory date and batch number.
7.1.2 Packaging Marks
The outside of the packaging box should be marked with:
Manufacturer name and address;
Product name and mark;
Trademark,
Packaging box dimensions, gross weight, net weight; Packaging storage and transportation diagrams drawn according to GB/T191. 7.2 Packaging
7.2.1 The measuring instrument should be packed in a dedicated packaging box. 7.2.2 The packaging box should contain the following documents:
A. Instruction manual;
B. Product certificate;
C. Packing list.
7.2.3 The structure of the packaging box should be able to withstand the various transportation tests required by this standard. 7.3 Transportation
The ambient temperature during transportation shall not be lower than -10℃. 7.4 Storage
The tester should be stored in a warehouse with an ambient temperature of 5-40℃ and a relative humidity not exceeding 85%, and avoid coexistence with corrosive substances. Additional remarks:
This standard was proposed by the Technical Equipment Department of the Ministry of Light Industry. This standard is under the jurisdiction of the National Dairy Machinery Standardization Center. This standard was drafted by the 5705th Factory of the Chinese People's Liberation Army. The main drafters of this standard are Lu Qiang and Zhan Jicheng. 287
Standard material fee is one-fold4 Storage
The measuring instrument should be stored in a warehouse with an ambient temperature of 5-40℃ and a relative humidity not exceeding 85%, and avoid coexistence with corrosive items. Additional remarks:
This standard was proposed by the Technical Equipment Department of the Ministry of Light Industry. This standard is under the jurisdiction of the National Dairy Machinery Standardization Center. This standard was drafted by the 5705th Factory of the Chinese People's Liberation Army. The main drafters of this standard are Lu Qiang and Zhan Jicheng. 287
Standard material fee is one-fold4 Storage
The measuring instrument should be stored in a warehouse with an ambient temperature of 5-40℃ and a relative humidity not exceeding 85%, and avoid coexistence with corrosive items. Additional remarks:
This standard was proposed by the Technical Equipment Department of the Ministry of Light Industry. This standard is under the jurisdiction of the National Dairy Machinery Standardization Center. This standard was drafted by the 5705th Factory of the Chinese People's Liberation Army. The main drafters of this standard are Lu Qiang and Zhan Jicheng. 287
Standard material fee is one-fold
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