The relationship between accuracy e and readability d of electronic balance

There is a big difference between the calibration scale graduation value e of the electronic balance and the actual scale graduation value d of the electronic balance
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(l) Relevant provisions of the calibration scale division value e ① The calibration scale division value is expressed in mass units, and it should take the following form: 1 x 10 to the k power or 2 x 10 to the k power or 5 x 10 to the k power Power where k is a positive integer, a negative integer, or zero
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② For balances with scales and no auxiliary devices, the calibration scale division value e is equal to the actual scale division value d
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③ For balances with scales and auxiliary devices, the calibration scale division value e shall be selected by the manufacturer according to Table 1 and the following rules: d For the balance of grade ① with d < 1mg, the manufacturer is allowed to choose the calibration points not according to the requirements of the above formula.
Degree value e
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Under normal circumstances, without the verification and approval of the verification department's type identification, the verification division value e should also obey the requirements of the following formula: e = 10 to the power of k (kg) In the formula: k - index, which is the positive adjustment, Negative integer or zero
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④ For non-automatic balances without scales, the calibration scale division value e shall be selected by the manufacturer according to the requirements in Table 1
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The above stipulations are the rigid stipulations of the "Non-automatic Balance Verification Regulations" of JJG98-1990
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(2) Different meanings ① d is the small scale or division value of the balance, and it is also called the small reading accuracy
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It is a small value of the balance itself, which can also be considered as precision
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According to the regulations, it is called the actual scale division value of the balance, and it is represented by the symbol "d"
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② e is the division value of the scale calibration scale of the balance, as the name implies, it is the division value used for calibration
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The division value used in this verification cannot be equal to the actual scale division value d of the balance.
It is not a fixed value like the d value, but a variable value that is artificially specified according to needs.

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can be specified
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e=10d, e=5d can also be specified, and even e=2d can be established.
As long as it does not violate the provisions of the national metrological verification regulations
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(3) Explain the actual scale division value d of the electronic balance, which indicates the small precision of the electronic balance, and the electronic balance calibration scale division value e is used to evaluate the technical indicators when the electronic balance is verified
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To be precise, the selection of the best accuracy of an electronic balance should not only depend on the d value, but also on the e value
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Especially in the departments of precise weighing, scientific experiments and value transfer, it is better to choose a balance based on the calibration scale graduation value e
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