CPU connection program input device.
Twisted pair cable.
Remote I/O station.
According to the control requirements of the system, using the appropriate design method to design MITSUBISHI PLC program.
Procedures to meet the requirements of system control as the main line,
Write one by one to achieve the control function or the sub task of the program,
Gradually improve the functions specified by the system MITSUBISHI A7PU.
MITSUBISHI PLC initialization procedure A7PU
After MITSUBISHI PLC on power, the general need to do some of the initial operation,
In order to start making necessary preparations, to avoid the wrong operation of the system.
The main contents of the initialization program are: to some data area, counter and so on,
Data needed to restore some of the data area,
Set or reset some relays,
For some initial state display, etc MITSUBISHI A7PU. . Input and output points: 1024 points.
Input / output data points: 1024 points.
Program capacity: 14K.
Basic command processing speed (LD command) s:0.20.
Optical data communication line function (GI cable).
Integral type: the PLC components are installed together or a few pieces of printed circuit board,
And together with the power supply installed in the casing to form a single overall called the host or the basic unit, small, ultra small PLC using this structure MITSUBISHI A7PU.
Modular: PLC is the basic components of a separate module.
Medium and large PLC used this way. Easy maintenance.
Each scanning process. Focus on the input signal sampling. Focus on the output signal to refresh.
Input refresh process. When the input port is closed,
Program in the implementation phase, the input end of a new state, the new state can not be read.
Only when the program is scanned, the new state is read.
A scan cycle is divided into the input sample, the program execution, the output refresh.
The contents of the component image register are changed with the change of the execution of the program.
The length of the scan cycle is determined by the three.
CPU the speed of executing instructions.
Time of instruction.
Due to the adoption of centralized sampling.
Centralized output mode.
There exist input / output hysteresis phenomena, i.e., the input / output response delay.
User program storage capacitty: it is a measure of how much the user application can store the number of indicators A7PU.
Usually in words or K words as units. 16 bit binary number is a word,
Every 1024 words are 1K words. PLC to store instructions and data in words.
General llogical operation instructions each account for 1 words A7PU. Timer / counter,
Shift instruction accounted for 2 words. Data operation instructions for 2~4.