The weighing instruments used in electronic weighing instruments belong to the category of precision instruments. The installation, use and maintenance of the weighing instruments must be done according to the requirements of the instructions in order to ensure the safety, normal and accurate of the instruments. Otherwise it may lead to instrument damage or shorten its service life.
1. installation: general should choose clean, dry, ventilated, suitable environment for the placement of meters. Instrument position should be fixed, do not move frequently, otherwise it may lead to signal cable plug internal lead shedding and failure.
2. Power supply: Weighing instruments (such as 8142, 8530 series) mostly use 220 volts AC power supply, voltage allowable range is generally 187 volts - 242 volts. After changing the power supply line, remember to measure whether the voltage meets the requirements before power on the instrument. If the 380 volt power is sent to the meter by mistake, it may cause damage. When the power supply voltage fluctuates greatly, it should be equipped with a good regulator (such as CW AC parameter regulator) to ensure the normal use of the instrument. Do not use the same power socket with strong interference sources (such as motors, bells, fluorescent lamps), so as to avoid instability of instrument display value. Some instruments (such as HAWK watch, etc.) are AC and DC. When loading dry batteries, it should be noted that the leakage of the battery will damage the instrument. Batteries should be removed when battery is not supplied for a long time.
3. Grounding: Weighing instruments should be connected with independent and good grounding wire (grounding resistance < 4 ohms, grounding lead should be as short as possible). Grounding wire has two functions: it not only protects the operator's personal safety, but also has an important anti-interference effect. It can ensure the instrument to work steadily. Grounding wire is connected to the instrument power socket. If the instrument ground wire is connected to the public strong electric protection ground wire, it may produce power interference to the instrument and make the instrument work stably. The display value fluctuates. Regularly check whether the ground connection points are in good contact. Because after a long period of time, the connection point oxidation, rust and other conditions will make the instrument actually does not work.
4. Sunscreen: Should avoid direct sunlight on the black shell of the instrument, otherwise it may cause damage to the working environment of the instrument beyond the rated temperature range.
5. Waterproof: In general, although the humidity of the working environment of the instrument can reach 95%, it is stipulated that no condensation can occur. Special stainless steel case with waterproof function.
6. Anti-corrosion: Corrosive material can not penetrate into the instrument, otherwise it will corrode the circuit board components and the circuit board itself, a long time, may make the instrument scrap. Even if the instrument with anti-corrosion function is not strict enough, it will have the same result.
7. Lightning Protection: Electronic weighing instruments belong to weak-current system, which are vulnerable to lightning attacks and damage components. Lightning enters the instrument mainly from two aspects: from the power line and from the weighing platform through the signal cable. In normal weather, the operator only needs to operate the power switch, but in case of close lightning strike, the instrument power plug and the scale signal cable plug must be unplugged. Lightning protection measures should be adopted, for example, surge protection devices should be added to the instrument power supply circuit.
8. Anti-strong electricity: 220 volts above the power line unexpectedly set up to the scale platform or use the scale platform as the ground wire, welding operation on the scale platform may damage the instrument.
9. Cleaning: In the industrial environment, there will be ash or contamination on the instrument shell, must be often wiped with a wet rag when power is off. However, it should be noted that alcohol and other solvents can not be used to wipe the display window, this will make the transmission of light deterioration, display blurred.
10. antistatic: once the meter is damaged, it must be repaired. Some units in order to speed up the transmission back and forth, like to instrument PCB board removed, using express mail, which produces an anti-static problem. When you take the PCB board, you must hold the four corners of the plate, and do not touch the place with the integrated block pin. Because it is easy to damage the integrated block by static electricity. Removal of the PCB board should be immediately packed in a shielding bag, in the absence of a shielding bag can be wrapped in ordinary newspapers. If you put the board on the high insulation desktop, you may damage the PCB board. When you receive the repaired PCB board and need to reload the meter, you should pay attention to static electricity as well.
11. Anti-vibration: When the instrument is transported, it is better to put it in the original packing box or take appropriate anti-vibration measures.
12. Explosion-proof: If the instrument is used in composite or intrinsically safe explosion-proof system, the relevant provisions of explosion-proof should be followed.
Responsibilities: Electronic weighing instrument is a relatively advanced weighing system, which should be specially operated and maintained by trained personnel. At present, most weighing instruments determine the function and performance of the weighing instrument by setting and correcting the parameters on the software. Once these parameters are arbitrarily changed, it may affect the accuracy and function of weighing (such as not printing or not communicating, etc.). Therefore, it is very important to determine the responsibilities of operators and maintenance personnel.