Working with plc's in electrical design software - The 5 basic rules

By Thor Vegge

Learn the 5 things you need to know in order to work with plc's quickly and effectively - in an advanced electrical design software as PCSCHEMATIC Automation.

When you have achieved a reasonable working knowledge in drawing electrical schematic diagrams, there are some extra facilities which might come in handy when documenting plc's. This will enable you to handle larger numbers of plc data in the documentation, and will give you a fast and efficient exchange of data with the plc software you use.

To phrase it in a popular way, you can say that there are 5 things you need to know, in order to achieve a fast and efficient workflow when documenting plc's in an electrical design software as PCSCHEMATIC Automation.

1. Get familiar with the options for using plc symbols

When documenting plc's, you need to know, that it is optional whether you apply large symbols for representing entire plc modules, or a number of small I/O symbols for representing the individual inputs and outputs on the plc. If you select the plc from a database, you can get an electrical symbol pickmenu, from which you can select whether to use the one type of symbols or the other.

You will save a lot of time by becoming familiar with the basic rules for working with plc's in PCSCHEMATIC Automation.

For those of the plc's, where this makes sense, they can already be addressed from the database. This can be done directly in the component manufacturer databases, or you can type in the data in your database once and for all.

2. Importing/Exporting plc I/O data

You can also save time by becoming familiar with how you can easily load plc I/O files from different plc programs. When you do so, the electrical design software will guide you through which consequences this will have. If you answer “Yes” to the import, the changes are transferred to all relevant places in the electrical documentation. Correspondingly, you can export plc I/O data from the electrical design software, PCSCHEMATIC, to the necessary plc programs.

3. Reference symbols for plc's

Especially when working with larger plc's, there can be a considerable amount of data attached to each individual plc. Therefore you should know, that when placing plc's, a so-called plc reference symbol is filled out, containing all data for this plc. When changes are made on the individual I/O symbols for the inputs and outputs on the plc, these changes are also displayed in the plc reference symbol.

When you make changes in the data via the plc reference symbol, these changes are also automatically transferred to the implied I/O symbols in the electrical documentation. When the address of an I/O symbol is changed, the other texts for this connection point is changed according to the information for this address in the plc reference symbol. When a plc I/O list is loaded, the survey symbols for the implied plc symbols are updated.

4. Changing data for plc's

Beyond how you apply plc reference symbols and import plc I/O data, it is good to have an overview of the other options for changing plc data in the program. This includes the so-called Object Lister, from which you can edit data for any type of objects in the electrical documentation, including plc I/O data.

You can also use the import/export functions in the program for editing plc I/O data via Microsoft Excel. Or you can save time by becoming familiar with the functions for automatic counting on project texts, e.g. connection names and addresses on plc's.

5. Text links and Text wrap

A final thing which makes importing plc I/O data considerably easier, is getting familiar with how to insert the so-called text links. When you, during import, change a plc information, which also occurs somewhere else in the project than next to the plc symbol, it is important that these texts are also updated throughout the project.

You can make sure that this happens by linking these texts with text links. When one of these texts are changed, the other linked texts are changed accordingly. Furthermore, it is practical to know how to specify that a text shall continue on a new line, when a specified text length is exceeded.

When importing plc I/O data this can be important for the appearance of the electrical documentation, because too long text lines will result in that you will have to clear up the mess in the documentation.

It is learned quickly

Learning these options does not necessarily require much of an effort on your part. A fast short-cut for also mastering this aspect of electrical documentation, could for instance be attending a course in the program, where you will also learn a lot of other program functions. The time spent in these courses, will pay back quickly in your daily work with the program.

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