1. When printing a ladder diagram, why aren't the comments printed?
To print a ladder diagram with comments LSS must be set to print in one of two graphics modes. To check this, go to the SETUP menu and select the PRINTER option. From this there are three settings that may be made - to print comments one of the two graphic modes must be selected.
2. When printing a ladder diagram in one of the graphics modes, the lines are not printed correctly. Why?
When LSS is set to print in one of the two graphics modes (see the PRINTER option in the SETUP menu) it uses the IBM graphic character set to print the lines and symbols that make up the ladder diagram. To print correctly the printer must support and be set to print with this character set. Depending on the printer you are using this may be achieved by using software parameters or DIP switches on the printer. For example, with the HP LaserJet III printer the symbol set needs to be set to PC-8.
3. How can I delete vertical lines?
Place the cursor at the bottom right of the vertical line you want to delete. Make sure you are in write mode (F2) then press F6 (for vertical line) then press the backspace key. The line should now have been deleted.
4. How do I connect a contact to an instruction that requires more than one input (such as KEEP and CNT)?
Place the cursor to the immediate right of the contact you wish to connect to the instruction. Press [CTRL] L (this is a short-cut key for the PROGRAMMING menu option, CONNECT LINE). Now place the cursor on the instruction where you want the line to be connected and press [RETURN]. LSS will now draw a line connecting the contact to the instruction.
5. When I try to save a ladder diagram the error Wrong data disk is given.
The reason for this error message is that a library file does not exist in the LSS directory. LSS saves all ladder diagrams, data memory settings, etc. in library files. LSS creates library files as PGC2000.DAT or PGC500.DAT, depending on the model PLC you are programming for.
To create a library file go to the UTILITY menu and select the CREATE LIBRARY FILE option. From this select the library size you require and the library type. For the library type there are 3 options - C2000H, C500 or both C2000H and C500. For C20, P-type, C120 or C500 select C500, otherwise select C2000H. If you select the "both" option then 2 library files will be created. Once a library file has been created you will be able to save ladder diagrams.
6. Can LSS have more than 1 library file?
Yes. Normally LSS creates library files as PGC2000.DAT or PGC500.DAT, depending on the model PLC you are programming for (see the answer to question 5 for more details). Once a library file has been created you can use the DOS RENAME command to rename the library file from PGC2000/500.DAT to any other valid DOS filename. The only requirement is that you keep the .DAT file extension.
7. When I try to insert a new instruction into an existing rung the message "Set Error" is given. Why?
The usual reason for this error is that there is not enough space in the ladder diagram to put the new instruction. To get round this, place the cursor where you want the new instruction, make sure you are in write mode (F2) then press [PAGE UP] 2 or 3 times. This will create some blank space in which you will be able to place the new instruction.
PRODUCT: LSS version 3.02.
WHAT IT DOES: LSS (Ladder Support Software) is a software package used for writing and documenting ladder programs for the C-series PLCs. LSS will run on any IBM PC or 100% compatible under DOS 3.20 or higher. The installation program supplied on the LSS discs is used to install LSS to the hard disc of your PC.
PROBLEM: Problems with installing and/or running LSS for the first time.
This helpsheet describes some problems that can occur when installing LSS or running LSS for the first
time. For details on how to install LSS see Helpsheet LSS_0001.
Some resident device drivers and programs may be incompatible with the LSS installation program or with LSS itself. For example, the first phase of LSS installation checks your system configuration. This should normally take only a few seconds, but if the process appears to be taking some time then the installation program has probably failed because of an incompatibility with resident programs. Such programs can include software such as multimedia, network drivers and CD-ROM drivers that are loaded by CONFIG.SYS and AUTOEXEC.BAT. Further, LSS requires between 530 and 590 Kbytes of conventional memory to run (this amount varies according to the size of the ladder program created). If your CONFIG.SYS and AUTOEXEC.BAT load several drivers or memory-resident programs then there may not be enough conventional memory left for LSS. If you use MS-DOS version 5 or higher then you can check how much memory there is available by typing MEM at the DOS prompt and looking at the line Largest executable program size on the returned information.
In order to overcome problems such as those described above, a basic configuration can be used. Helpsheet LSS_0001 gives example CONFIG.SYS and AUTOEXEC.BAT files that should allow LSS to install and run successfully. However, if your PC is not dedicated to PLC programming then it may not be convenient to swap from your standard configuration to the basic one whenever LSS is required.
MS-DOS version 6 and higher provides the facility to choose different configurations via a menu within the CONFIG.SYS file. The following example shows how to convert a single configuration into a dual-purpose one.
The lines shown below should be inserted at the beginning of CONFIG.SYS, with the existing lines in the file immediately following the label [standard]:
menuitem = standard, Standard Configuration
menuitem = LSS, Configuration for LSS
menudefault = standard
Append existing lines of CONFIG.SYS here
The lines shown below should be added to your AUTOEXEC.BAT file. All the lines except for :End should be inserted above the existing lines:
loadhigh c:doskeyb uk,,c:doskeyboard.sys
Insert existing lines of AUTOEXEC.BAT here
The above example is a suggested solution to the problem of needing multiple configurations. It is suitable for a 386 (or better) computer with at least 1 MB RAM. If you have installed LSS in a directory other than C:LSS you should substitute your directory name in the path statement shown above.
For more information on multiple configurations consult your MS-DOS manual or type HELP MULTI-CONFIG on your computer at the DOS prompt.
Installing LSS and backing-up discs: W237-E1-1A, pages 40-51
Running LSS: W237-E1-1A, pages 52 on
PRODUCT: LSS version 3.02.
WHAT IT DOES: LSS (Ladder Support Software) is a software package used for writing and documenting ladder programs for the C-series PLCs. LSS will run on any IBM PC or 100% compatible under DOS 3.20 or higher.
PROBLEM: When trying to print the ladder diagram in one of the graphics modes the ladder diagram lines are not printed correctly.
When LSS is set up to print in one of the graphics modes (see the LSS SETUP menu, PRINTER option) and a ladder diagram printed the ladder diagram may not be printed out correctly. For example, horizontal lines may appear as rows of ....... or with the Hewlett Packard LaserJet IIIP or 4L.
The reason for this is that the correct Symbol Set has not been selected (Symbol Set is Hewlett Packard terminology for a specific collection of alphabetic, numeric and special symbols in a font). When LSS prints a ladder diagram in graphics mode it uses the IBM graphic character set to build vertical and horizontal lines. Using this graphic character set, the ASCII code for a horizontal line character, i.e. , is 196. One Hewlett Packard symbol set that supports this is PC-8. If the symbol set is set to Roman-8 then ASCII code 196 will be printed as an and if set to Windows it will be printed.
Another setting to make on the printer is to ensure that a compressed font has been selected. This will usually be a 17 character per inch font, although the Hewlett Packard printers set this to 16.67 cpi.
So, it is important to ensure that the correct symbol set and font size have been selected. With the HP LaserJet IIIP this is easy as you can select them from the menu buttons on the printer. With printers such as the HP LaserJet 4L it is not as straightforward since there are no such menu buttons and any settings must made by sending commands to the printer via the PC.
One way of making these commands is to create an ASCII text file and send this file to the printer by using the DOS COPY or PRINT commands. The following has been tested on an HP LaserJet 4L and DeskJet 1200C. Using the MS-DOS EDIT program, create a text file containing the following codes, then use the DOS COPY or PRINT commands to send the file to the printer. The codes required are:
Set symbol set to PC-8
Set compressed font
Set line spacing to 8 lines per inch (note that the "l" in this code is a small letter "L").
Save the file and print it out. Next, run LSS and try printing a ladder diagram.