PCS7 CFC Process Object View: Bulk-Edit Textual Connections

Overview

SIMATIC PCS 7 Continuous Function Chart (CFC) uses two distinct I/O attributes — Signal and Parameter — that govern how the Process Object (PO) view resolves a block interconnection. When an output of a block in CFC_A must drive the input of a block in CFC_B by a textual name (e.g., FC111_PV, PID_1173/SP), the receiving block I/O must be declared as Parameter. Declaring the same I/O as Signal forces the compiler to treat the entry as a memory address (DB bit / periphery address) rather than as a free-text connection target, which prevents the bulk-editing workflow that the PO view is designed for.

This reference explains the configuration steps to flip an I/O from Signal to Parameter, populate the Interconnection column in the PO view, and verify the link after CFC compilation. It is written for PCS 7 V9.0 SP2 through V10.0 with the Advanced Process Library (APL) V9.x or V10.0 master data, and is applicable to both AS-side CFC charts and OS-side runtime blocks where textual cross-chart references are required.

Prerequisites

• SIMATIC PCS 7 V9.0 SP2, V9.1, V9.1 SP1, or V10.0 with matching hotfixes installed on the Engineering Station (ES).
• PCS 7 APL Master Data Library installed (PCS7 APL V10.0 for V10.0 systems, PCS7 APL V9.0 for V9.0 SP2 systems). Older PCS 7 standard library blocks (FB100-class legacy types) do not expose the Parameter attribute on every I/O.
• SIMATIC Manager (for V9.x) or PCS 7 Engineering in the TIA Portal (for V10.0) configured with at least one S7-400 / S7-410 / AS 410 / AS 410E station in the plant hierarchy.
• Two CFC charts already created in the same or sibling hierarchical folders (e.g., Unit_1/Motor_CFC and Unit_1/Valve_CFC). The source block resides in chart A; the destination input resides in chart B.
• Read/write access to the PCS 7 project database. PO-view column editing requires the same Windows user permissions as standard CFC editing.
• Familiarity with CFC inter-chart signal routing rules and the difference between global DB interconnections and textual connections.

Signal vs Parameter I/O Attribute Semantics

Every block I/O in a CFC block type (FB) carries a configurable attribute declared in the block type's interface description. PCS 7 exposes two attributes that affect PO-view behaviour:

Process Object View Column Reference

The Process Object view (right-click chart folder → Process Objects) is a tabular editor that exposes one row per block pin across all selected CFC charts. The most relevant columns for cross-chart textual routing are:

The same physical pin appears in either the Signal tab or the Parameter tab depending on its attribute. PCS 7 hides columns that are not relevant to the current attribute to prevent accidental misuse.

Step-by-Step: Re-declare I/O from Signal to Parameter

1. Open the destination CFC chart (CFC_B) in the chart editor and click the destination block (e.g., CTRL_PID or MOT_SPEED).
2. Open Block Properties via right-click → Object Properties → tab I/Os.
3. Locate the input pin (e.g., SP, PV, LIOP) that will receive the textual connection. The Attributes column shows the current declaration.
4. Click the Attribute cell and select Parameter from the dropdown. Confirm with OK.
5. Save the chart. PCS 7 prompts for a delta download — decline if running only on the ES; accept if the AS is online.
6. Right-click the chart folder containing CFC_A and CFC_B, then choose Process Objects → Parameter tab.
7. The destination input now appears in the Parameter tab with an editable Interconnection column.

Bulk-Editing Workflow for Cross-Chart Textual Connections

1. Open the Process Object view of the parent hierarchy folder (e.g., Unit_1) so all relevant CFC charts are aggregated.
2. Switch to the Parameter tab. Sort by Block or apply a filter on the destination I/O name (e.g., *SP*) using the filter row.
3. Identify the source block output in CFC_A that must be referenced — note its chart-and-pin path, e.g., MOT_1203/AV.V or FC111/PCOUT.
4. For each row in the destination filter set, paste the textual reference into the Interconnection column. The format must be <chart_name>/<block_instance>.<pin> or <block_instance>/<pin> when the block resides in the same chart.
5. Press Enter after each paste; PCS 7 validates the string and color-codes the cell — green text indicates a resolvable reference, red text indicates an unresolved target.
6. To copy/paste a recurring pattern (e.g., the same signal routed to 30 instances), select the first validated cell, press Ctrl+C, select the remaining target rows with Shift+Click, and press Ctrl+V. The PO view pastes the interconnection into all selected rows.
7. Save the Process Object view. PCS 7 prompts to update the underlying CFC charts; confirm with Yes.
8. Run Charts → Compile on the affected S7 program. Verify that no warnings appear in the Logs window.

Interconnection Naming Conventions

PCS 7 textual interconnections must comply with the S7 symbolic name rules: max 24 characters, must start with a letter, allowed characters A-Z, a-z, 0-9, _. The full path syntax used in the PO view is:

If the source and destination blocks are in the same CFC chart, the <chart_name>/ prefix may be omitted. Cross-chart references always require the chart prefix, and PCS 7 resolves the prefix against the plant hierarchy at compile time. Cross-AS references (one S7 program to another) are not supported through PO-view textual connections — they require either a Global DB link or an S7 connection routing via PUT/GET SFB calls.

Common naming patterns used in PCS 7 APL projects:

• <TAG>/V — process value (PV) of an analog tag
• <TAG>/SP — setpoint
• <TAG>/MV — manipulated variable output
• <TAG>/STA_RUN — running status bit
• <TAG>/MOUT.V — motor control output value

Compilation Behaviour and DB Generation

When a textual interconnection is compiled:

1. PCS 7 enumerates every textual connection and generates a corresponding S7_connection entry in the chart's runtime DB.
2. The compiler creates per-chart instance DBs (typically DB 1–DB 999) for blocks whose pins carry Signal attribute interconnections.
3. For Parameter-attribute connections, no instance DB bit is allocated. Instead, the symbol is referenced by name, and the OS runtime map resolves the connection during OS download.
4. If the textual reference cannot be resolved (target chart missing, pin name changed, or attribute still on Signal), the compiler emits warning W: 'X' unresolved textual interconnection and the affected connection is excluded from the runtime DB.

To inspect the compiled textual connections, open Charts → Cross References and filter by Textual Connections. This lists every textual inter-chart link and its resolved target.

Verification Checks

1. After bulk-editing, run Charts → Compile → All on the affected S7 program. The compile log must report zero unresolved textual interconnections.
2. Open Charts → Cross References → Textual Connections and confirm each edited row appears with a green resolved icon.
3. Download the S7 program to the AS (full download for first-time connection additions; delta download for incremental edits).
4. On the OS, perform Download → Entire WinCC Project to refresh the runtime database. The block icon for the destination block must show the live value of the source output within one OS update cycle (default 1 s, configurable in OS Project Editor → Picture Update).
5. In the CFC online view, place PCS 7 in Test Mode and watch the destination pin — its value must track the source output in real time.
6. Open the Process Object view, select the affected rows, and verify the Value column shows non-default runtime values.

Troubleshooting Matrix

Field-Proven Caveats

• Legacy block types: PCS 7 standard library blocks predating APL V8.0 do not expose Parameter on every I/O. For those, either upgrade to APL or create a derived block type with the attribute overridden in the type FB interface.
• Cross-AS: The PO view cannot resolve references between separate S7 programs. Use an S7 Global DB or BSEND/BRCV pairs with the source block's value written to a shared DB area.
• Type FB vs Instance DB: For multi-instance projects (common in unit templates), confirm that the destination block is an instance of a type FB, not an instance of an instance DB. Parameter routing through instance-of-instance chains can fail silently.
• OS block icon re-link: When the destination block's name changes, every OS block icon referencing it must be re-linked. PO view does not automatically update the OS-side wiring.
• Compile order: In multiproject setups with several AS stations, always compile the source-side AS first, then the destination-side AS. PCS 7 validates cross-chart textual references only after the source S7 program is compiled.
• Documentation in PDF manuals: The official procedure is documented in the PCS 7 Engineering Manual, section "Working with the Process Object View," available via the Siemens Industry Online Support portal at support.industry.siemens.com.

FAQ