Electronic balance works:
The electronic balance uses the principle of electromagnetic force balance to achieve weighing. Before the weighing plate is loaded, the balance is in an initial equilibrium state. After the weighing pan is loaded, the balance is in an unbalanced state. Under the action of the weight of the weighed object, the light shielding plate moves downward, so that the light-emitting diode D2 senses the light emitted by D1, and the light signal is converted into a voltage signal by the photoelectric detection circuit . The voltage signal is adjusted by PID to provide a moving coil (movable coil) with a current proportional to the mass of the weighed object. Under the action of the magnetic field of the permanent magnet, the moving coil will generate an upward force F to move the light shielding sheet upward. After the light-shielding plate is moved upward, the output voltage of the photoelectric detection circuit is reduced, and the PID integration link causes the current flowing through the moving coil to continue to increase until the light-shielding plate returns to the initial equilibrium position, and automatic electromagnetic force compensation is realized.
The use environment of electronic balance:
To use the electronic balance well, you must have a suitable location and environment.
1 Choose the right weighing platform
It should reduce vibration as much as possible; do not tilt when working; have anti-magnetism; have anti-static protection; place on the ground or fixed on the wall, but do not use both methods at the same time; if conditions permit, it is better to use the vibration damping special for balance station.
2 Choose the right place
Avoid direct sunlight and keep away from the interference of heating, air conditioning and no detectable airflow; the workbench should be placed in the corner of the room, away from magnetic fields, or choose the strongest and least vibration place in the building.
3 Choose the right work environment
Although the laboratory electronic balance has not strict requirements on the working environment temperature and humidity, it is best to control the temperature between 15 ° C and 30 ° C. Humidity is in the range of 50% to 70% RH.
Electronic balance maintenance:
The electronic balance manufacturer introduces you that the correct care and maintenance have a great effect on the life of the balance and the correctness of the weighing result.
(1)The electronic balance should be kept and maintained by a special person, and a technical file bag should be set up to store the instruction manual, verification certificate, test records, and regular records of maintenance and repair.
(2) The electronic balance room should be kept clean, tidy and dry to prevent dust or other debris from entering the housing of the electronic balance.
(3) Do not open the cover arbitrarily, so as to avoid desoldering or short circuit of the electronic circuit, which will affect the work of the electronic balance and even damage the components. The load on the weighing pan must not exceed the rated limit, so as not to overload the balance and cause damage to the balance.
(4) Clean the weighing pan, casing and air hood frequently. Generally use a clean silk cloth with a little ethanol to wipe gently. After the balance is cleaned, a non-corrosive desiccant should be placed in the frame and replaced regularly.
(5) The measurement performance of the balance should be checked and calibrated regularly. If the electronic balance fails, it should be repaired in time, and it should not work with "illness".