woodward 8402-319 touch human-machine interface operation screen

woodward 8402-319 touch human-machine interface operation screen

Several steps in programming
（1） Determine the actions and sequence required by the system.
When using programmable controllers, the most important aspect is determining the inputs and outputs required for the system. Input and output requirements:
(1) The first step is to set the number of system inputs and outputs.
(2) The second step is to determine the order of control, the corresponding relationship between each device, and the reaction to be made.

Number input and output devices
Each input and output, including timers, counters, built-in registers, etc., has a unique corresponding number and cannot be mixed.

（3） Draw a ladder diagram.
Draw a ladder diagram according to the action requirements of the control system.
Ladder diagram design rules
(1) The contacts should be drawn on a horizontal line and based on the principles of left to right, top to bottom, and the control path for the output coil.
(2) Branches that do not include contacts should be placed in a vertical direction to facilitate identification of contact combinations and control paths for output coils.
(3) When there are several series circuits in parallel, the series circuit with more contacts should be placed at the top of the ladder diagram. When there are several parallel circuits connected in series, the parallel circuit with the most contacts should be placed on the far left side of the ladder diagram. This arrangement results in a concise and clear program with fewer statements.

(4) Cannot draw contacts to the right of the coil.

（4） Convert the ladder diagram into a program
Convert the relay ladder diagram into the code of a programmable controller. After completing the ladder diagram, the next step is to compile its code into a program that the programmable controller can recognize.
This programming language is composed of serial numbers (i.e. addresses), instructions (control statements), and device numbers (i.e. data). Address is the location where control statements and data are stored or placed, and instructions tell programmable controllers how to use devices to make corresponding actions.

（5） Enter the program using the keyboard in programming mode.

（6） Programming and designing control programs.

（7） Test the control program for errors and make modifications.

（8） Save the complete control program.