PLC IN THE ELEVATOR IN THE
APPLICATION OF ELECTRIC CONTROL
ABSTRACT
Elevator, with the high-rise building construction and developed a kind of vertical transport. However, the complexity of the elevator control system, so that relay contact control system wiring complexity of the possible use of hundreds of kinds of relays, by a number of conductors connected in complex ways, so that if a relay damaged or contact their connections will affect the normal operation of the whole system. As science and technology development and wide application of computer technology, people elevator safety, reliability, have become increasingly demanding, relay control weaknesses on the increasingly apparent. Given all the advantages of PLC, at present, the elevator relay control method has gradually been replaced by PLC control. At the same time, due to motor AC inverter technology, elevator drag ways have the original DC drive gradual transition to a communication speed. Thus, PLC control technology increases frequency control industry has become a hot topic in modern elevator. PLC automatic control technology applied to lift a very good solution to the elevator control system is too complex issues.
As a general-purpose industrial control computer, (PLC) can be programmed using the memory used in its internal memory implementation of the logical operations, sequence operations, timing, counting and arithmetic operations such as instruction, and can be digital or analog input and output to control various types of machinery or production process.
After years of application of PLC has been continuously developed, with significant advantages. Due to the internal circuitry to an advanced anti-jamming technology, with high reliability. PLC development today has formed a series of all sizes, product can be used for occasions of all sizes to industrial control. PLC logic with memory logic, instead of wiring, greatly reducing the control equipment external wiring, so that control system design and construction of the cycle is much shorter, while maintaining them becomes easier. It also has a small size, light weight, low power consumption advantages. Because of these advantages PLC technology has a wide range of industrial control applications in various fields, this four-story elevator in the PLC technology to achieve automatic control is a good example.
The system design is to use Mitsubishi PLC (FX2N) as an elevator control device.