One of the efficient ways of effectivety of blast smelting is switching to pulverized fuel. The effectiveness of replacing coke pulverized fuel in the blast smelting depends largely on the equitable distribution of fuel in the coal lance of the blast furnace. Only if there is continuous monitoring parameters pulverized plants may implement regulation thermal treatment furnace and thus reduce fuel consumption. To that end, technological equipment must be equipped with an automated control system using innovative technical tools and solutions in schemes of automation systems - microcontrollers and micro-computers. The reason is that the flexibility of microprocessor systems provides a radical expansion of functional technical means of automation, particularly in relation to information which serves increasing production of organization, uninterrupted operation of the plant under optimal conditions, improving safety, etc.
To create an effective system of governance an important issue is to develop subsystems automatic data input from sensors in computers. Under automation of installations for insufflation of coal fuel different types of sensors are used, both with discrete electrical output signal and analog. The sensors are scattered in space and located at a distance of approximately 1000 meters from the control room furnace. Therefore when developing the system of management one of the stages is solving the problems.
The combination of sensors with computer management system presupposes the existence of complex devices andcertain rules that provide those or other types of compatibility: the presentation of information, special. This means that properties signals of primary information of sensor should be brought into line with the characteristics of normalized entrance to the mainframe.
To this end, a special device - a data adapter (APD) of primary information from sensors in computers has been developed(Fig 1). Adapter device, is universal it can be connected to either analog digital, or simultaneously discrete and analog gauges. Data input from sensors in the Microcontroller is carried out through the harmonization of BS block, where: the transformation of current analog signals from the sensors into a signal voltage; is carried out being isolated lines of communication adapter contact sensors; Microcontroller adapter protection from possible surges in the lines connecting sensors is implemented.
Fig 1. A data adapter (APD) of primary information from sensors in computers.
The main element is Microcontroller adapter, which receives information from sensors, processes and stores data in memory, and also controls the transfer of data to the mainframe.
To transfer data from the microcontroller to a central computer a special adapter contains a transmitting unit - transmitter serial interface standard RS485. Standard RS-485 provides with information for us both parties agreed on symmetrical lines. The transmitter has a login manager, converting its exits into high impedance state in which they are actually disconnected from the line of communication. This makes it possible to connect up to 32 adapters to the same line length not exceeding 1200 m, that meets the operational requirements to the system of control. The adapter has a unique power supply, which provides the necessary level of tension elements of the device.
The principle of the adaptor is: when receiving a request from a computer to obtain information on the controlled parameter, Microcontroller adapter implements poll and putting in signals from the analog or discrete sensor. Processing occurs in Microcontroller and, if necessary, the accumulation of current values of a controlled setting. The information is transmitted to the computer at the remote controller.
The adapter is placed directly at the sensor and is connected to a computer separate twisted pair cables and is working continuously.
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