The balance is mainly divided into three categories: electronic analytical balance, electronic balance and mechanical balance, as follows:
First, the electronic analytical balance
There are many types of analytical balances: mechanical, electronic, manual, semi-automatic, fully automatic, and so on.
Calibration method of analytical balance: it can be divided into internal school type and external school type. The so-called internal calibration is that the electronic balance has an internal calibration weight, which is convenient to be retrieved at any time, and one-button calibration is performed. The external calibration type must be manually adjusted by pressing the calibration key and putting weights from the outside.
Second, Hunan electronic balance
1. Check and adjust the balance to a horizontal position.
2. Check in advance whether the power supply voltages match (if necessary, configure a voltage regulator), and power on according to the instrument requirements to warm up to the required time.
3． Turn on the balance switch after warming up for a sufficient time, and the balance will automatically adjust the sensitivity and zero point. After the stability mark is displayed, formal weighing can be performed.
4． When weighing, place a clean weighing bottle or paper on the weighing pan, close the side door, and press the tare key lightly. The balance will automatically calibrate the zero point, and then gradually add the substance to be weighed until the required weight.
5. The weight of the weighed substance is the actual value displayed on the display when the “→” mark appears in the lower left corner of the display.
6. The weighing bottle (paper) should be removed in time after the weighing is completed, the side door should be closed, the power should be cut off, and the use situation should be registered.
Third, mechanical balance
1. Slowly turn the lifting pivot button to turn on the balance and observe the swing range of the pointer. If the pointer swings to one side, you can adjust the zero adjustment screw on the balance beam.
2. Put the material to be weighed into the center of the left pan from the left door, and use the tweezers to grab the appropriate weight according to the initial weight first weighed on the tray balance. Lifting pivot button (because the mass difference between the two sides of the balance is too large, the lifting lever of full lifting may cause the lifting ear to fall off and damage the blade), depending on the deviation of the pointer, increase or decrease the weight. After the weights of the gram group have been tested, adjust the travel code. In the process of adjusting the balance of the balance with the travel code, the right door must be closed. At this time, all the lifting pivot buttons can be raised. After the pointer swing stops, the scale indicated on the label should be at or near zero