PLC Automatic Control Research Articles

Application of PLC Automatic Control Technology in Frequency Conversion Control

Application of PLC Automatic Control Technology in Frequency Conversion Control

Research on High Pressure Fine Mist Cultivation Equipment

Most of the existing aerosol cultivation equipments are bulky, simple-structured and poor in functional stability. Based on this, the author developed a set of automatic control high-pressure fine mist cultivation device, designed the PLC automatic control circuit, and simulated and tested the temperature and humidity change curves. The test results verify the simulation model and the overall device runs well, among which the spray atomization process, and the temperature field, humidity field and velocity field under three atomization modes are simulated. Three atomization schemes are analyzed, and in the end the optimal one is selected. In comparison, the side-by-side spray is completely covered; the atomization is more sufficient. The results show that the time when the humidity reaches 90% in the same position is different under different initial humidity conditions. The atomization humidity maintenance time in different environments is approximately the same, and can be maintained for 4 to 5 hours. It can be seen from the comparison of the results that the greater the humidity, the shorter the heat exchange time and the faster the heat exchange.

Design of Wireless Communication System in Mine

In order to improve the control efficiency of large equipment such as scraper, transporter and crusher, and reduction in personnel, increased security factor, based on PLC automatic control and wireless interconnection technology, a mine wireless communication system including wireless control host, wireless handheld and wireless relay substation is developed. The system carried out industrial experiments on the mining face in coal mine. The test results show that the system is easy to install and maintain, the equipment is stable, the wireless signal covers no blind areas, the call is clear, the data transmission is reliable, and the wireless remote control of the large equipment is achieved.

Based on the PLC Technology Automation Design of On-board Pump Station Oil Temperature Control System

Vehicle hydraulic pump station, often work environment is poor, the environment temperature difference is very big, the nature of the hydraulic oil is affected by temperature is very big, a lot of damage, PLC automatic control scheme and design of pumping station, the oil temperature automatic control system realized the automation of the oil temperature control, greatly improving the pump station of the outdoor environment to adapt to the performance.

Concentration of Nitrate in Main Anoxic Stage and PHA, TP Metabolism for Nitrogen and Phosphorus Removal in Single Sludge System with Continuous Flow

Based on test results and mass balance, PHA, TP metabolic regularity was revealed under different nitrate nitrogen concentrations in main anoxic stage [c(NO3)] for nitrogen and phosphorus removal in single sludge system with continuous flow, then the effectiveness of using c(NO3) as control parameter was proved from the perspective of the reaction mechanism. During experiment period, the influent COD, total nitrogen (TN), and total phosphorus (TP) concentrations were stabilized at (285.78±18.19), (58.13±3.79), and(7.14±0.51) mg·L-1, respectively. The experiment was carried out under the condition that the c(NO3) values were 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 and 4.0 mg·L-1 based on the feedback control structure using PLC automatic control system to control the nitrifying liquid flow with the water quality. The sludge load of COD was (0.253±0.071)kg·(kg·d)-1, the sludge load of TP in anaerobic stage was (0.006±0.001) kg·(kg·d)-1, the sludge load of TN in aerobic stage was (0.049±0.006) kg·(kg·d)-1, the hydraulic retention time (HRT) in bioreactor was 9h, the sludge recycle flow was 0.5, and the mixed liquor recycle was 1.0. The results showed that effect of c(NO3) value on PHA synthesis and storage rate in the ANS was conspicuous, and the percentage of PHA storage occupied 74% of COD removal when c(NO3) value was 2.5 mg·L-1.The impact of c(NO3) value on PHA degraded in the main anoxic stage was great, and the percentage of PHA degradation in the main anoxic stage occupied 55% of total PHA degradation when c(NO3) value was 2.5 mg·L-1. The phosphorus released in anaerobic stage changed along with increasing c(NO3), and the amount of phosphorus released obtained the maximum value 6.16 g·d-1 when c(NO3) value was 2.5 mg·L-1. In addition, under c(NO3) value of 2.5 mg·L-1, the amount of total phosphorus uptake and anoxic phosphorus uptake obtained the maximum values of 8.04 g·d-1 and 3.67 g·d-1, respectively. Then it was confirmed thatc(NO3) could serve as a run controlling parameter with the best value of 2.5 mg·L-1 from the perspective of PHA and TP metabolic mechanism.

Improvement Research PLC Automatic Control System Based on Small and Medium Logistics Classification

PLC automatic control classification system is based on commitment to increase express courier company and distribution center for the delivery of processing power, making it more efficient for the shipment have free processing capabilities. Based on the scientific method, prior to the courier company handling capacity estimates, and the company in shipment processing equipment capital investment to enhance the product in the industry's competitiveness. It is used of the existing two-dimensional code scanning recognition technology. Through the automatic identification of microcontroller programming combined ratio for the sensor to achieve classification. It works to reduce logistics costs in the classification of goods while improving the efficiency and accuracy of their goods classification.

Based on PLC the Automatic Constant Pressure Control Water Supply System Design

This article is based on PLC automatic control of variable frequency constant pressure water supply system in the application of beverage factory, the automatic water supply system of constant pressure control method and reasonable design. Analyses the composition of control system structure, working process and PLC ladder diagram control process and the touch screen man-machine interface design. The system is reliable in performance, convenient operation, high automatic degree, intuitive interface, has higher application value.

Automatic Control System of Stone Sawing Machine Based on PLC and Human-Computer Interface

This paper designs a PLC automatic control system in stone cutting. The author elaborated the stone cutting process, the system hardware/software design and the human-machine interface design process. This system is the collection of PLC, sensing detection, frequency converter, configuration control technology and advanced stone cutting process in an organic whole. The author designed optional automatic/manual function and parameters setting screen. The author added limit current protection and position protection, and designed function of automatic detecting cooling water shortage to protect the saw blade from damage. Also the designed equipment can automatic light and bell for alarm. Operation results show that, this system can meet the designed requirement, and can remarkably improve the quality of stone processing. This designed control system has high machining accuracy, high intelligence, full automation, perfect protection, friendly man-machine interface and simple operation.

PLC Automatic Controlling System of Flushing Toilet

A kind of PLC automatic control system which is used to flush toilet consists of programmable controller, proximity switch sensor and solenoid valve. By means of proximity switch sensor receiving input signal with the core PLC, PLC gives motion instruction to control solenoid valve carrying out flushing toilets automatically. In addition, this paper presents controlling procedure of ladder diagram. In the practical process of application, the system is of high sensitivity and good stability, at the meanwhile, the hardware circuit is simple and easier to be maintained. As far as the system is concerned, the system can be applied to different places with appropriate designs of procedure. Owning to the good universals and low cost there is better prospect for application.

Automatic Control System of Copper Pipe and Aluminum Pipe Butt Resistance Welding Machine

It becomes a tendency that the application of copper pipe and aluminum pipe welding joints in the field of refrigeration. Based on analysis of Cu-Al pipe welding process, a PLC automatic control system was developed to accurately control the resistance welding machine. The executive mechanism is composed of pneumatic components and controlled by the PLC system to complete the Cu-Al pipe welding process. Under the PLC control, the welding time parameter can be changed, according to the pip size. And the time error of the control system is limited in 0.01s. When the coil temperature rises up to 90°C or the network voltage fluctuates more than ±10%, the control system alarms the operator and the welding process can not be started.

김치생산용 알타리무 전처리가공시스템 개발 (IV) - 시작기의 자동화와 평가 -

An Altari radish pre-processing system, which feasible to process automatically such operations as leaf and root tail cutting and root peeling, for kimchi production was accomplished based on the foregone serial studies. In this study, the performances of the developed prototype machine, considered as a commercializing level, were analyzed and evaluated. The prototype machine attached Tiny PLC automatic control system was performed the sequent function as the rate of successful peeling was more than 98% for the Altari radish less than 70 mm diameter of a radish. The operating efficiency of this was 9 see/each, 128 kg/h, and it means as much as <TEX>$5{\sim}6$</TEX> times that of a woman labor's. The sanitation and taste of the mechanized-processed Altari radish kimchi was almost same as that of the handmade. And they were suitable for manufactory of kimchi as the both short term ripening and storing kimchi. Developed machinery with one peeling device and two peeling devices that compared with hand processing, it was analyzed that the break-even yearly working days were 28 days and 19 days, and the break-even yearly processing amount were 28,700 kg, 32,400 kg, respectively.