Operations Manual


Process Simulation Screens
Working Through The Menus
The Rung Editor






Psim has been designed to minimize the amount of typing required on the part of the student. To this end, most instructions are accessed by way of the IBM function keys F1 through F10. Throughout this documentation, a specific function key will be referred to as [F1], [F8] etc. The student should note the definition of each function key is displayed on the bottom 2 lines of the colour display. Function keys may take on different definitions depending upon what operation is currently being executed. Students are encouraged to maintain a watchful eye on the status lines to see how the [Fn] definitions change thus minimizing the frustration due to miss-hit keys. The various functions are grouped together in logical order ensuring a minimum number of key strokes.

Typing <PSIM> at the DOS prompt will result in the start-up of the PSIM simulation program. After a period of initialization the main PSIM introductory screen will appear which contains the copyright notice for the PSIM program and an animation of the PSIM logo. After the animation has completed one cycle, a momentary prompt will appear stating: 'Press Any Key To Continue'. Pressing a key at any time while the introductory screen is showing will cause the main PSIM menu to be displayed. The animation will continue, but the menu which lists the available choice of process simulations will remain displayed.

To select one of the process simulations, simply press the number key on your keyboard that corresponds to the menu entry you desire.



Process Simulation Screens

On each of the process screens the student will notice that beside each piece of equipment e.g.. The electric motor in the silo simulation is a label describing the device i.e.. "Motor" and a PLC I/O address associated with that device i.e.. "O:1/00". When writing a program to control pieces of hardware always ensure that the correct I/O address is used. Please note that all addresses used in this simulation software use the following convention; the first character is either an "I" (input) or an "O" (output), next is a ":" followed by a single digit, a "/" and finally two digits. This naming convention must be adhered to if the devices are to be controlled properly.



Working Through The Menus

First level [Fn] key definitions

Once any of the processes have been selected a new animated process will be displayed. On the status lines of any of these processes will appear the first of a series of layers of [Fn] key definitions. With only minor exceptions all these definitions are the same regardless of which process is being used. Fig. 2 is a representative sample.

Fig. 2 Process Simulation Menu

[F1],[F2],[F3]   These [Fn] keys represent normally open(NO) or normally closed(NC) momentary switches which may be used at the programmers discretion for such function as START and STOP buttons to control the operation of the process. In some processes there are two such switches and in others there are three.
[F5] Rung editor: Used to switch from the process display mode to the program writing mode. Programs are written in the program creation mode and the tested out in the process display mode.
[F6] Exit (Esc) Exit back to the main menu
[F7] Toggle Table Successive taps on this function key will display different areas of the PLC data table on the screen beside the process. This function is useful as a program debugging tool

Rung Editor

This function is invoked whenever program creation or modification is required. Do not forget to "SAVE" the program whenever any changes are made to the logic. Figs 3 through Fig. 8 depict the [Fn] key definitions used in the Rung Editor mode.

Fig. 3 Main Editor Menu

[F1], [F2] Append, Insert Rung Used to Append a new rung after the current cursor position or to Insert a new rung ahead of the current cursor position.
[F3] Modify Rung Used to modify an existing rung.(Fig. 8)
[F5] Delete Rung Used to delete a complete rung from a program.
[F6] Un-Del Rung Used to paste back into the program a rung that had previously been deleted. Used in combination with [F5] rungs may be moved a rung, in total, from one area of a program to an other.
[F7] Program Utility Sub-Menu used to save or to retrieve user programs.
[F8] Clear Memory Used to completely erase program memory so that a new program may be written.
[F10] Exit Editor Exit this menu, back to process mode.


Fig. 4 Input Instruction Menu

The menu in Fig 4 is activated whenever Append rung or Insert Rung is requested. The [Fn] definitions for this menu are:

[F1], [F2] XIC, XIO Basic input instructions( see Relay Logic Instructions).
[F3], [F4] Branch Start, close Used together to form a series of parallel instructions. Parallel instructions form a logical OR operation.
[F8] Output Instructions Sub-menu containing all output instructions.
[F10] Exit back to the main edit menu.

Fig. 5 Output Instruction Menu

The menu in Fig. 5 is activated whenever an output instruction is requested. The [Fn] definitions for this menu are as follows (these instructions are more fully described in "Relay Logic Instructions and Timers and Counters"):

[F1] OTE Output energize.
[F2] OTL Output latch
[F3] OTU Output unlatch.
[F4] TON Timer on delay
[F5] RTO Retentive timer
[F6] CTU Count up counter
[F7] CTD Count down counter
[F8] Res Reinitialize counters and retentive timers
[F10] Prev-Menu Return to main edit menu.

Fig. 6 Word Compare Menu

The menu in Fig. 6 is activated whenever a Compare Instruction is requested in the main edit menu Fig. 4. The [Fn] definitions for this menu are as follows (these instructions are more fully described in "Word Compare Instructions"):

[F1] EQU Word value is equal in value to a specified immediate value
[F2] NEQ Word value is not equal to a specified immediate value.
[F3] GRT Word value is greater than a specified immediate value
[F4] LES Word value is less than a specified immediate value.
[F5] GEQ Word value is greater than or equal to a specified immediate value.
[F6] LEQ Word value is less than or equal to a specified immediate value.
[F8] Output Instructions Used to select the output instruction menu
[F10] Prev. Menu Menu Used to return to the main Edit menu

Fig. 7 Utility Menu

The utility menu in Fig. 7 is activated whenever the unity request is made (Fig. 3). This menu provides basic functionality for program storage and retrieval. Program names are not required for these files. File names are assigned at storage time and these same names are used upon retrieval.

[F1] Save Program Used to save a program so that it may be retrieved at a later date. File names are assigned for each process. Files are saved in the default directory.
[F2] Load Program Used to re-load a program that has already been saved ([F1]).
[F3] Print Program Used to print a program to the DOS Device PRN:
[F4] Program Directory Used to display a directory of ladder programs saved to date.
[F10] Exit Utility Exit back to main edit menu.

Fig. 8 Rung Modification Menu

The menu in Fig. 8 is activated whenever a modify rung request is made from (Fig. 3). Modification implies that the rung already exists, and that some minor changes are required. The [Fn] key definitions for this menu are as follows:

[F1],[F2] Append, Insert Instruction Used to Append (Insert) a new instruction to the right (Left) of the instruction under the cursor.
[F3] Delete Instruction Used to Delete the instruction under the cursor.
[F4] Change Instruction Used to Change the instruction under the cursor. Modifications include changing the address of the instruction or changing the instruction itself.
[F10] Accept Instruction Used to accept the rung once all of the modifications have been completed






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