The dosage scale completes the weighing and proportioning of the main material and various ingredients. After mixing and blending the ingredients, they are grouped and categorized for filling. It realizes the measurement of dosage scale sub-filling, adopts DCS centralized control mode, and selects Siemens S7-300 PLC to constitute the data acquisition and control system, which is modularized design and economical and practical. The human-machine interface monitoring software adopts the leading configuration software "Configuration King" in the field of industrial control, which has the advantages of good openness, easy maintenance and secondary development. All process control data and equipment operation status can be centrally managed, recorded in real time, and printed and consulted at any time. The structure and function of dosage scale is composed of computer, cabinet and peripheral equipment (weighing reactor, pneumatic control valve, transfer pump, etc.).

The dosage machine has the functions of human-computer interaction, communication, display and storage, printing, etc. The weighing module also has data and graphic display, status monitoring, data input, information storage and other functional screens related to operation. The system can realize real-time process data monitoring, simulation display of process flow, real-time data record access, system operator privilege setting, process parameter setting, setting of running process event alarm and manual and automatic control switching. In the monitoring system, the on-site control instrument displays real-time flow rate, load, totalized value, temperature and so on. Temperature indication through the field temperature display instrument, pressure indication through the field pressure display instrument and motor current through the field display instrument is transmitted to the centralized display in the control room. The frequency converter is equipped with automatic switching switch and communicates with the main control computer.

The automatic weighing control unit is mainly a 10-inch screen weighing and dosage meter (equivalent to 10 weighing and dosage meters), PLC as an auxiliary control system, computer human-machine interface displaying dosage parameters (formula) and monitoring and recording real-time data. In automatic control mode, click the automatic dosage "start" button in the screen, or the control cabinet "start" button, the weighing control instrument will open the weighing valve of 10 scales according to the set recipe. If the system detects that the dosage valve of a scale is not closed, an alarm occurs and the system enters the pause state. Each scale has an advance according to the weighing speed. When the control instrument detects that the weighing weight of the scale reaches the set value, the advance will be subtracted and the control instrument will close the feeding valve. The amount of advance can be corrected manually or automatically, so that the control instrument can control the dosage scale every time the dosage accuracy reaches the set target value.

The automatic Dosage system is to put the weighed raw materials into the mixing scale in a certain order, and the weighing instrument turns on the mixing and heating at the same time. This control process is accomplished by the temperature control meter and PLC. The temperature control meter controls the upper temperature limit and the heating is controlled by PLC. Automatic batching has two kinds of control methods: fixed order and programmable. In the fixed-order mode, the order of discharging all kinds of raw materials is fixed and cannot be changed. In programmable mode, the feeding order of all kinds of raw materials can be set artificially on the human-machine interface according to the recipe.