The types and functions of weighing instruments are very many, and because it is an electronic product, it is also necessary to be extra careful when selecting, and the following points should be noted when selecting:
1. Weighing instruments belong to trade settlement instruments, so the national strong inspection table series also includes such instruments. In practical applications, it should be considered whether the purchase of weighing instruments is used for trade settlement or only requires ordinary process weights; If it is used in trade settlement, then it is necessary to consider the verification scheme of the weighing instrument and the measurement of the accuracy level; If it is just an ordinary process, it is only used in the production workshop, you can not consider the problem of compulsory verification, but the accuracy still needs to be measured according to your actual situation.
2. The measuring accuracy of the weighing instrument has a relatively large impact on the price of the instrument, so the selection of the weighing instrument should be made according to its own accuracy requirements; Now the country for the general provisions of the trade scale when the precision of one thousand, there is no clear requirements for the process scale, generally determined by the owner, the conventional process scale of the system accuracy of one thousand can basically meet the requirements. The accuracy of the weighing instrument is related to the precision of the weighing sensor and whether the installation of the weighing sensor is standard.
3. There are also requirements for explosion-proof selection of weighing instruments; The equipment installed in the site of the weighing system must meet the corresponding explosion-proof requirements for the occasion of explosion-proof on-site requirements for the weighing sensor, weighing instrument and weighing junction box; If the weighing instrument is installed in the place of the principle sensor, then its explosion-proof grade can sometimes be lower than the explosion-proof grade of the weighing sensor, but the specific situation can be determined according to the actual situation on the site.
4. Weighing instruments are generally divided into two types, weighing display instruments and weighing control instruments, and the price gap between these two types is also very large; Weighing display instrument only weight display, signal transmission these requirements are not; However, many industrial occasions generally require weighing instruments to send weighing data to the DSC system for display control, according to the requirements of the scene, pay attention to the choice of signal transmission methods, generally choose analog or RS485, RS232, Modbus and other communication methods, the price of these requirements of the instrument is also different. When choosing, we should communicate with the manufacturer to determine the communication method before the manufacturer can conveniently select the quotation.
5, weighing instrument in the selection should also pay attention to the size of the on-site power supply, the instrument power supply is divided into 220V and 24V, different power supply for different sites, if the choice of wrong may burn the internal circuit board of the weighing instrument and can not be repaired.
6, in the selection of weighing instruments should also consider the installation of on-site instruments, instruments are generally divided into desktop, embedded and track; Table instrument can be placed on any surface for weight display, display instrument mostly, in the use of weighing can be seen at any time after the weight changes; The embedded and track instruments are generally placed in the stainless steel control box, and it should be noted that the size of the instrument should be confirmed with the manufacturer when selecting these two instruments, so as to prevent the opening error and the installation cannot be carried out on the site.