Application of PLC in the plate vulcanizing machine control system: since 1969, the first programmable controller (PC) in the United States, has been widely used in industrial control. In recent years, our country in the petroleum, chemical, machinery, light industry, electricity, electronics, rubber, plastic processing industries such as electrical control of process equipment, more and more, it adopts PC computer control, and has obtained the remarkable effect, is popular among industries.
Our factory was started in 1988 the application of programmable controller in the vulcanization machine, usage has been good so far. Below to omron company's C200H programmable controller.it, for example, talk about the application of PC in the vulcanization machine.
1 the characteristics of the welding mechanism by C200H programmable controller.it
(1) the system is flexible.
(2) high reliability, strong anti-jamming ability, good adaptability to the environment.
(3) the function is strong.
(4) the instruction is rich, speed, fast, easy programming.
(5) fault diagnosis ability is strong, has the self-diagnosis function.
(6) a variety of communications functions.
2 on the [vulcanizing machine] an advantage of using the programmable controller
(1) to simplify the input device and its wiring, such as universal change-over switch, button from the complex of the combined group is simplified to a single set of combinations. Limit switches, buttons, and other wiring can receive only a set of points (normally open or normally closed), another state by PC internal identification, which greatly reduce the peripherals connection name.
(2) use the software instead of the relay connection. Change control is convenient. PC machine adopts microcomputer as the core of the electronic circuit, is the combination of a variety of electronic relays, timers and counters, and the attachment (that is, the internal connection between them through the instruction with programmer. If in accordance with the requirements for the change control mode, modify the control line, just a programmer to modify instruction can, is very convenient.
(3) using semiconductor devices will relay contact control to PC contactless control, greatly improved. J on the phase stability, the original relay control at fault, such as relay coil, coil adhesion, burn out lines cabinet and not tight and contact falls off, the relay itself fault eliminate.
(4) to expand I / 0 hunger, there are two power supply model options: (1) the use of 100 ~ 120 ~ 240 vac or 200 vac power; (2) using a 24 VDC power supply. Input devices such as buttons, select switch, trip switch, pressure regulator and other available 24 VDC power supply as the signal source, which can avoid the production environment temperature is too high and cause short circuit phenomenon such as trip switch, pressure regulator, improved the security of the maintenance workers, reducing the maintenance port. Output can be driven directly by 200 ~ 240 VDC power supply solenoid valve, contactor output load, etc.
(5) in addition to the CPU, battery errors, scanning time, memory errors, Hostink, remote I/O errors such as fault self-diagnosis functions and can judge the PC itself, corresponding to the I/O each point has the signal light, indicating the I / 0 0 n/OFF state, depending on the I/O lights display can be accurately and quickly determine the PC peripheral equipment failure.
(6) according to the control requirements, can be easily constitute the most appropriate system, and is easy to extend. If vulcanizing machine to increase and improve the peripheral control system, in the main CPU and extension elements, after the equipment to be connected to the Internet, can be easily constitute a system.
3 how to vulcanizing machine programming
(1) the whole process of [vulcanizing machine] is normal operation must do the action, as well as the relationship between them.
(2) determine the trip switch, button, etc. As the input signal is sent to the PC input devices required input points; Solenoid valve, contact the output equipment of such as receiving signals from PC output the desired output points. Then assigned to each input and output points a I / 0, at the same time distribution of "internal relay" (IR) or work and timer/counter.
(3) according to the relationship between the output device and the order of the control object must be action (or time), and draw the ladder diagram.
(4) if you use the GPC (graphics programmer), FIT intelligent terminal (factory) or LSS (IBMXTAT programming software) can use ladder diagram logic program PC directly, but if you use ordinary programmer, must put the ladder diagram is converted into a mnemonic (composed) address, instructions and data.
(5) using the programmer or GPC test program, and correct errors, and commissioning program, and to observe the operation of vulcanizing machine, is consistent with our requirements, and then modify the program, until the most perfect program.
4 the common faults of vulcanizing machine control system
It adopts PC computer control vulcanizing machine failure rate is low, the fault generally occurs mainly in the following aspects.
(1) input devices
Like trip switch, button, switch after repeated action, will produce the phenomenon such as loose, no longer, or even damage.
(2) the output device
Due to environmental humidity and pipeline leak phenomenon, make the electromagnetic valve water, short-circuit, burn out electromagnetic valve. The phenomenon of light also often have burn out.
Due to the output device many times short circuit, a high current, impact within the PC output relay, and make the output relay contact melt and adhesion together, damage the relay.
The maintenance and maintenance
(1) in the installation of the PC machine, it must be from the following environment: corrosive gas; Rapid changes in temperature; Direct sunlight. Dust, salt and metal powder.
(2) use must be checked regularly at ordinary times, like some wearing parts (such as insurance, relay and batteries, etc.) often need to change.
(3) the unit output by 220 vac output in each group, must be at least a 2 a250vac fuse, burn out when the insurance, be sure to check the group if there is a different output devices. If you don't check immediately changed into new insurance and is easy to damage to the relay output unit.
(4) to watch battery alarm light at ordinary times, if the warning lights flashing, you must replace the battery in a week (replacement battery should be finished within 5 min), battery life expectancy for 5 years (under room temperature 25 ℃).
(5) when the CPU and the expansion of the power removed, when install the wiring must connect to, otherwise it is easy to burn out the CPU and the expansion of power supply.