How to evaluate the quality of electronic balance?

One: The definition of electronic balance:

Balances are weighed on the principle of electromagnetic force or electromagnetic torque balance.

Two: Classification of electronic balances: According to the structure of the use of sensors can be divided into three categories: strain sensor electronic balance, ceramic sensor electronic balance, electronic magnetic electronic balance. Strain-type electronic balance scales are small and accurate. Ceramic sensor electronic balance has a large range of low precision. Electromagnetic force balance uses the principle of electronic magnetic force has the characteristics of high accuracy and stability, but the range is not high.

Three: Measure the performance parameters of the electronic balance: stability, linear accuracy, repeatability, sensitivity, and service life.

1. Stability: Stability in electronic balances can be divided into: instantaneous stability and long-term stability (creep). Instantaneous stability refers to the value displayed by the electronic balance immediately after the balance is placed on the measured object and remains unchanged; long-term stability means that the electronic balance does not change much in the ambient temperature, and the same weight is maintained for a long time after the power is turned on. The difference in the change over time. The smaller the difference between the above parameters, the more stable the performance of the electronic balance.

2. Linear Accuracy: refers to the accuracy of each point in the weighing range of the electronic balance. (Note: The electronic balance consists of several weighing points within the weighing range. For example, an electronic balance of 300g consists of 0.1g, 0.11g, 0.12g, 0.13g, 0.14g, 1.00g, 1.13g, 5.00g, 10.00g , 20.01g ... to 299.99g, 300.00g and other points of composition). The more weighing points measured at the time of purchase, the better the electronic balance can be purchased. Poor quality electronic balances are only accurate at the weight calibration points, other weighing points may have large differences, and each weighing point can be measured using standard weights. The higher the accuracy level of the weight, the better the accuracy of the weighing point.

3, repeatability: In the electronic balance refers to the same measured object weight, multiple repeated weighing, each time the difference between the displayed values, the smaller the difference the better. Such as: 50.00g, 50.01g, 49.90g, 49.99g, 50.10g The smaller the difference between them is better.

4. Sensitivity: In the electronic balance refers to the time limit reflected by resolution and resolution. The resolution means that the smaller the value of the calibration index e or the display resolution d, the better (high sensitivity). To reflect the time limit, the electronic balance will increase the sensitivity, and the value will increase as soon as the value of a sensitivity value is shorter. The top equipment analysis expert believes that the electronic balance reflects fast and has high sensitivity.

5. Service life: The service life refers to the estimated period during which an enterprise uses fixed assets, or the quantity of products or services that the fixed assets can produce. The longer the life, the better. Customers can measure the lifespan of electronic balances by providing them with the characteristics of the electronic balances warranty period.