Language

1. Use English language [+]
2. Observe valid characters [+]

Use English language

A PLC program (program code, variable names, comments etc.) is written entirely in English. American English is recommended here.

Observe valid characters

The names of program elements and variables may only contain the following characters, numbers and special characters:

• 0...9
• A...Z
• a...z
• Underscore character '_' as the only valid separator (more information below)

Double underscores ('__') should generally be avoided, because they are used for internal variables.

Use of the underscore character '_':

The underscore character '_' as the only valid separator is provided for the following designations:

• For objects between prefix and object name. Samples:

FB_GetData, ST_BufferEntry, I_CylinderControl, E_StandardColor 

• Optional to implement a sorting scheme of objects in the project tree