The three beam balance was named because of its three scale horizontal bar scale. The three beam balance has three groups of riding codes, but no weights first use the maximum riding code if the pointer does not return to zero and then adjust the smaller scale. The three beam balance has three crossbars, each cross bar has different mass weights placed on it. The position of the mobile weight can be adjusted to the size of the balance pivot and the relative side resistance of the object. The items to be measured are filled in the weighing paper or in the weighing disc and then placed on the balance plate of the balance. When the gravity of the object is equal to the resistance of the weight, the position of the beam should be in a horizontal state. At this point the position of the scale at the tip of the most right side of the beam should be on the zero reading. Therefore, if the quality of a thing is to be measured correctly, the balance itself must remain in a state of level. Some scales can find the adjustment knob and bubble level indicator on its base. When weighing an object, the sum of the quantity displayed on the weight position on the three bars can be read when the balance has reached the horizontal position, which is the quality of the object to be measured. The three beam balance, which is commonly used in the general laboratory, has a precision of 10mg.
Since the balance bar is supported on the top edge of the tapered column at the top of the pole, it is necessary to light the object to be measured when using the balance, so as to avoid affecting the measurement accuracy due to accidental impact on the fulcrum. Most of the scales need to turn a spanner when they are not in use. After pulling it up, the bar can be lifted up and the wedge support is separated and locked to ensure the safety of the balance. When used, trigger the wrench first and return to the normal position.