PLCs (Programmable logic controllers) are contributing a more significant function as the systems they run develop larger and more complex. Nowadays users are challenging PLCs with reduced software development cost, higher performance, more sophisticated functions, and high reliability. This article describes on the PLCs of MELSEC QnA series built to meet these requirements.
Background
The QnAS and QnA series have been planned to raise the user program development. Efficiency and improve execution performance this was reached by initiating enhancements number to the previous corporation PLC products:
1. Support for prearranged programming lets multiple designers to do on a project.
2. Programs can be consistent.
3. Easily studied user interface pursue the commercial software packages model.
4. All of the performance has been scaled up throughout improvements in the networking interface processor units, and data bus.
5. Extensive device capacity and program memory simplicity program design restrictions.
6. Products of compact QnAS Series are existing for embedded applications. MELSEC QnAS packed in PLCs; other requirements are the same with the QnA Series.
System Configuration
The QnA Series PLC basic components a: CPU modules with high-performance, there are fifteen memory cards, network interface modules considered to match closely with the modules of CPU, a CPU base unit of high-speed access that increases all of the performance and a software package offering total program development support. The new series preserve toward the back compatibility with accessible MELSEC A Series CPU base units, modules of power-supply, most special-function units and I/O units.
Features
CPU modules for both series utilize dedicated processors built at Mitsubishi Electric. The top-end CPU module provides double the performance of its predecessor with an operating speed of 0.075µs. There are four CPU modules for the two for the QnAS Series and QnA Series, let’s processing the capability and capacity memory to be in the range to the application. The CPU module of high-speed admission provides double the data through of previous tool, and the memory cards which offer access of high-speed to support complicated systems such as real time control.