Electronic balance is an instrument that uses the principle of electromagnetic force balance for high-precision weighing. Its core is to achieve accurate measurement through the interaction between electromagnetic force and object gravity. The following is a detailed analysis of its working principle:

1. Electromagnetic force balance mechanism: When the measured object is placed on the scale, its gravity causes the coil in the sensor to shift or deform. The position detector inside the sensor will capture this change and generate a weak signal. After feedback from the amplifier, the signal increases the current in the coil. This current generates an electromagnetic force opposite to the direction of gravity in a constant magnetic field until the two reach equilibrium.

2. Signal conversion and processing: During the balancing process, changes in coil current are transmitted to the measuring resistor (Rm) and converted into voltage signals. Subsequently, the signal undergoes filtering and analog-to-digital conversion (A/D) to convert the analog signal into a digital signal, which is then processed by a microprocessor. The monitor will display the mass value of the object in real time.

3. Closed loop control system: PID regulation technology is used to perform proportional, integral, and derivative control on signals to ensure fast and stable system performance. For example, one signal enters the feedback coil to maintain dynamic balance, while the other is used for quality calculation, forming a closed-loop control.

Precautions for using electronic balance:

1. Environmental requirements

-Avoid vibration, airflow, direct sunlight, and corrosive gases, and choose a stable and level countertop.

-The room temperature should be uniform to avoid drastic changes in temperature and humidity that may affect accuracy.

2. Operating standards

-When weighing, move gently and open the balance door gently to avoid impacting the sensor.

-Overloading is strictly prohibited, and the temperature of the object being weighed must be consistent with room temperature.

-Use tweezers or gloves to pick up and place items to prevent contamination or corrosion of the balance.

3. Maintenance and upkeep

-Regularly replace desiccants (such as color changing silicone) and keep the box clean and dry.

-When not in use for a long time, preheat the instrument for 2 hours every week to maintain its performance.

-Clean up the residue on the scale plate in a timely manner to avoid cross contamination.

4. Other details

-The same experiment should use the same balance and matching weights to reduce errors.

-Mechanical reinforcement requires step-by-step operation to avoid collisions; When moving the balance, it is necessary to disassemble key components to prevent damage.

By following the above precautions, the measurement accuracy of the electronic balance can be ensured and the service life of the equipment can be extended. The specific operation needs to be adjusted according to the instructions of different models.