There are many people bought for micro-electronic of reflection, not many long time is broken, opened it and found that some parts was old, such electronic scale must be refurbished, and electronic scale buy to return, says things are not sell, a thing, you said if not, the somebody else find door scale, this is not well, so we hit business in the choice of electronic scale, must pay attention good the following:
A, about the electronic scale of calibration

Before using (you have to read through FangChan) in check (test) we found, for the first time in electronic scales measurement error when large proportion, investigate its reason, a department in a long time, the instrument in the distance without calibration, and thought that he can demonstrate zero directly weighing. (need to point out is, electronic scales boot shows zero, cannot explain the data accuracy of weighing electronic scale with test scale, can explain electronic scale zero not disorderly qualified. A balance due to measure whether or not qualified, still need to comprehensive consideration of the other technical indexes of compliance). For a long time storage, position, environmental change or move to obtain the accurate measurement, electronic scales before use general electronic scale error display should be calibrated to operate. Calibration method within and outside the calibration calibration is divided into two. This Wallace weighing apparatus series electronic scales even have calibration device. If use before don't read carefully FangChan very easily ignored "calibration" manipulation, cause bigger weighing error. Here in this Wallace weighing apparatus factory as an example to demonstrate how the electronic scale calibration.Methods: CAL lightly in a key when the display CAL-which let go, the display is a CAL 100 among them, "100" to flash code, says calibration farmar need 100 g of the scale of the Jordan farmar. This time put ready "100 g" calibration farmar to put on a plate, display that is called "-" wait for a long time, the state after a display 100.000 g, take to calibration farmar, a 0.000 g monitor should, if not for a zero, then the reset again, and repeat above calibration manipulation. (note: in order to obtain the correct calibration results best repeat the calibration)Second, choose electronic scale. Attention

(1) how to choose the electronic scale

Choose from the electronic scale should demonstrate absolute accuracy (dividing value e) up considering whether to comply with weighing accuracy. If choose the accuracy of the 0.1 mg balance or 0.01 mg precision balance, avoid by all means is not in general terms to one over ten thousand or one over one hundred thousand precision of the electronic scale, because foreign some manufacturer with relative accuracy is to measure the balance, or buy electronic scale with the needs of the user can't.
For example in practical work met such a situation, with a real ruler dividing value for 1 mg, verification d ruler dividing value e for 10 mg, the biggest weighing 200 g for the Mettler electronic balance, used to weigh 7 mg of objects, this is not the correct results in the JJG98-90 the automatic balance trial calibration regulations to be, the biggest error and promised to gauge verification indexing value "e" unified level, the number for the biggest promised to Taiwan electronic scale error for 1 e,Obviously can't weighed 7 mg objects; Weighing the object used the 15 mg balance also isn't the best choice, because of its relative error of the test results will be very big, should choose to a higher level of electronic scale, some manufacturer with a factory has defined a multimeter with minimal resistance measurement usually stand or fall of weighing values. So we in the choose and buy and use electronic scale precision grades have to be considered.
(2) the weighing range of requirements

Choice except to see its precision, electronic scales should also think the biggest whether the need of weighing content range. Usually take maximum load to add a few insurance coefficient can, is also used to relax some can, load is not the bigger the better.