Where to Find the Meaning of PCS 7 APL Faceplate Symbols
Use the documentation for the installed Advanced Process Library, matching both the symbol's shape and the faceplate area in which it appears. Siemens' APL Operator Guide provides consolidated tables for signal status, group displays, interlocks and tracking indications. Its documented V8-era examples are a useful reference, but an unspecified installed release must be checked against its own help. A symbol's color alone is insufficient to identify its meaning or prescribe a repair.
Table of Contents
- Match the Library and Display Area
- Use the Documented Symbol Tables
- Verification
- Limitations and Operational Precautions
- Engineer FAQ
- Technical References
- Related Articles
- Related Tags
Match the Library and Display Area
Record the APL version and the block/faceplate type. Capture the symbol and its location without including private plant information. Determine whether it belongs to signal quality, a group-message display, an interlock indication or another operating-state area.
The opened APL Operator Guide, Operating Manual, 05/2011, discusses APL block icons and faceplates with V8.0 examples. Its chapter 4 describes faceplate operation. Configuration work belongs to the applicable library help and Style Guide rather than an operator-symbol table.
Use the Documented Symbol Tables
Open the APL Operator Guide and use these relevant sections:
The signal-status table distinguishes Bad, device related from Bad, process related, and likewise distinguishes the two uncertain-quality categories. It also lists simulation/function-check and maintenance-required indications. Do not compress these into a single generic fault.
For example, the guide uses a sensor wire break to illustrate device-related bad quality. That example is not proof that any particular displayed symbol is caused by a wire break.
Verification
As an engineering identification procedure:
- Match the actual icon against the illustration in the applicable section and installed library edition.
- Read its accompanying meaning, including device/process distinctions.
- Compare the identified category with the measurement-point diagnostics and current operating state.
- If the illustration or faceplate layout differs, stop assigning a meaning from that edition and obtain the correct library reference.
Successful identification means the exact illustration, context and definition agree. It does not establish a root cause or authorize simulation, bypassing or a device reset.
Limitations and Operational Precautions
The installation's library version is unspecified, so the historical guide is not a universal dictionary for every later faceplate. A reported red spanner should be matched visually to its applicable table rather than diagnosed from the word red.
The reported availability of a question-mark help button in every faceplate was not independently established. Use installed context help where the actual faceplate provides it, without assuming a particular button layout.
Inspect diagnostics before acting. Do not bypass interlocks, enable simulation or acknowledge away a condition simply to remove an unfamiliar symbol. No fault repair is prescribed by this identification article.
Engineer FAQ
Are all red symbols equivalent? No. Interpret the exact symbol and its display category.
Does bad quality identify the failed component? It is a diagnostic category; establish the cause with the actual signal path.
Can an operator guide replace configuration instructions? No. It explains the displayed operation and meanings.