Configuring KTP700 Basic DP with S7-300 CPU 315-2DP via TIA

Overview

Integrating a SIMATIC KTP700 Basic DP (2nd generation) into a legacy CPU 315-2DP project originally built in STEP 7 V5.3 is a common migration scenario. The CPU 315-2DP (order number 6ES7315-2AG10-0AB0 or equivalent) communicates natively over PROFIBUS DP, and the KTP700 Basic DP (6AV2123-2GA03-0AX0) is the matching 7" panel with a PROFIBUS DP interface. The migration path is the Device Proxy PLC technique: a TIA Portal project acts as a placeholder for the STEP 7 V5.x CPU, while the actual CPU keeps running its original V5.x program. The HMI is fully engineered in TIA Portal and points at the proxy for tag resolution.

This article covers the full workflow: opening the V5.3 project, exporting source containers, building the TIA Portal project with a proxy PLC, configuring the KTP700 Basic DP hardware, and downloading both projects. It also covers the firmware prerequisites, GSD file handling, and typical compile-time corrections that appear when blocks move between the two engineering environments.

Prerequisites

Before starting, confirm the following hardware, software, and firmware requirements. Skipping these checks is the most common cause of proxy-PLC compile failures and "device not found" download errors.

Workflow Comparison: Three Migration Options

There are three legitimate engineering paths. Pick the one that matches your project size, runtime risk tolerance, and whether the V5.x program must stay untouched.

The remainder of this article focuses on Option A: Device Proxy PLC, which is the lowest-risk path described in the original query. Option B is covered in the troubleshooting section for users who attempt it.

Step 1: Prepare the STEP 7 V5.3 Project

Before exporting anything, the V5.3 project must be opened in STEP 7 V5.5 (V5.3 cannot export sources in the format TIA Portal imports cleanly). Siemens' own Application Example Combined configuration with WinCC (TIA Portal) and STEP 7 V5.x documents this exact workflow.

1. Open SIMATIC Manager with administrator rights.
2. File → Open → Browse to *.s7p project, click Open.
3. If prompted about a version upgrade, accept the conversion. The program logic is preserved; only the project container format changes.
4. Select the S7 Program container in the project tree.
5. Run Edit → Check Block Consistency from the menu. Resolve all reported errors before exporting. Most V5.3→V5.5 migration errors are address-scaling issues in FB/FC parameter types.
6. Run PLC → Compile and Download Objects with "Compile only" to verify the hardware configuration is consistent.

Step 2: Export Source Containers from STEP 7 V5.5

The Device Proxy PLC only exchanges the symbol table, DB layouts, and FB/FC/OB signatures with TIA Portal. It does not retranslate the V5.5 code. The HMI in TIA Portal binds to the same tag names that exist in the V5.5 symbol table.

1. In SIMATIC Manager, expand S7 Program → Sources.
2. Insert a new STL source: Insert → S7 Software → STL Source. Name it export_all.
3. Open the new source, then in the program editor select File → Generate Source → Export All Blocks to Source File.
4. Save the source. The container now holds every OB, FB, FC, DB, and UDT as STL text.
5. Right-click the source file → Export to External Source. Save with extension *.src in a known folder (e.g., C:\TIA_Migration\sources\).
6. Repeat for the Symbol Table: Options → Symbol Table → Export. Save as *.asc.

The exported files are plain text. You can open them in Notepad to verify they contain the FB/FC/DB declarations you expect. This is also a useful cross-check: if a block is missing from the export, it is not accessible to the TIA Portal HMI.

Step 3: Create the TIA Portal Project with Device Proxy PLC

1. Launch TIA Portal (V15.1+). Create new project → name it, set the project path, author, comment.
2. In the project tree, click Add new device → Controllers → SIMATIC S7-300.
3. Search for CPU 315-2DP. Select the exact order number that matches the physical hardware (e.g., 6ES7315-2AG10-0AB0). Using the wrong MLFB will cause firmware-mismatch warnings at download time.
4. Confirm the device view shows two interfaces: MPI/DP (X1) and DP (X2). Configure DP on the X2 port as PROFIBUS master with address 2 (the default CPU address is 2 on most S7-300 projects; change to match your V5.x project).
5. Convert the S7-300 CPU to a Device Proxy: right-click the CPU in the project tree → Cross-compiler → Initialize Device Proxy. A new DeviceProxy folder appears with placeholder I/O.
6. Browse to the STEP 7 V5.5 project file (*.s7p) and link it. TIA Portal reads the symbol table, DB structure, and FB signatures from the V5.5 project without altering it.

Step 4: Add the KTP700 Basic DP to the Project

1. In the TIA Portal project tree, click Add new device → HMI → SIMATIC Basic Panels.
2. If the KTP700 Basic DP is not listed, install the matching HSP from Options → Support Packages. Restart TIA Portal after installation.
3. Select KTP700 Basic DP with the correct MLFB (typically 6AV2123-2GA03-0AX0).
4. A new Devices & Networks editor opens. The panel appears with one PROFIBUS DP port.
5. Drag a PROFIBUS connection from the panel's DP port to the proxy CPU's DP port (X2). TIA Portal automatically creates a subnet named PROFIBUS_1.
6. Set the panel's PROFIBUS address to a free value (default 1 is usually fine; 1 is the engineering station, 2 is the CPU, 3 is the panel).
7. Open the panel's Properties → PROFIBUS interface → PROFIBUS profile and set the bus profile to DP with the highest supported baud rate (1.5 Mbps is a safe default; 12 Mbps works with shielded cable and short stubs).

Connection Editor Verification

Open Connections on the panel. The connection to the proxy CPU should be listed as S7ONLINE with a green status indicator. If the indicator is red, the proxy link in step 3 is broken — re-run Initialize Device Proxy and confirm the V5.5 project path has no spaces or special characters.

Step 5: Import Symbols and DB Layouts from V5.5

1. On the HMI side, open HMI tags in the project tree.
2. Select Import from STEP 7 V5.x. Browse to the *.asc symbol table exported in Step 2.
3. TIA Portal creates a flat tag list pointing at the proxy CPU. Tags with DB addressing are expanded into HMI-compatible structures based on the DB layout read from the V5.5 project.
4. Verify a sample of tags: open the Connections → S7ONLINE on the panel and click Test connection. Tags in the HMI tag table should resolve to the proxy without "address not found" errors.

If the symbol table import reports unresolved references, the most common cause is a renamed or deleted tag in the V5.5 project. Open the V5.5 symbol table in SIMATIC Manager and confirm the tag still exists with the same name and address.

Step 6: Engineer the HMI Screens

Use WinCC Basic (bundled with TIA Portal) to build the operator screens. The KTP700 Basic DP supports the standard Basic Panel object set: buttons, I/O fields, symbolic I/O fields, bars, gauges, date/time fields, alarm views, trend views, recipe views, and screen navigation. It does not support scripting (VBS, C), archives, audit, or Sm@rtServer. If any of these are required, upgrade to a Comfort Panel.

1. Create a Screen in HMIs → Screens. Start with the Root screen that loads at runtime.
2. Insert an I/O field bound to a tag from the imported symbol table (e.g., DB100.Motor_Speed).
3. Insert an Alarm view to surface bit-triggered alarms from the V5.5 program. The alarm class Errors and Warnings map 1:1 to the KTP700 color scheme.
4. Configure the Connection area: Connections → S7ONLINE → Properties → Mode: select Normal for the Device Proxy, Safety Integrated only for F-CPUs.

Step 7: Compile and Download

Two separate downloads are required: the V5.5 project to the CPU, and the TIA Portal project to the KTP700. The Device Proxy means there is no project conversion to perform on the PLC side — the CPU continues to run the same V5.5 program.

1. In SIMATIC Manager, select the S7 Program and PLC → Download to Target System → CPU 315-2DP. The CPU goes to STOP briefly, then RUN.
2. In TIA Portal, right-click the KTP700 Basic DP → Compile → Software (rebuild all). Resolve any warnings — "Address area not available in Device Proxy" typically means a tag references a slot the proxy could not read.
3. Right-click the KTP700 Basic DP → Download to device → PC Interface → select the PROFIBUS CP (e.g., CP5611 / CP5711) or Ethernet PN route.
4. Confirm the panel reboots and shows the root screen. The connection icon in the system bar should be green.

Full Migration (Option B) Notes

If you elect to convert the V5.x project to TIA Portal instead of using the proxy, the workflow is:

1. Open the V5.5 project in TIA Portal using Project → Migrate project. TIA Portal V15.1+ can read V5.5 projects directly; older TIA Portal versions require a *.zap archive.
2. Import the STL source container from Step 2: External Sources → Import. Right-click the imported source and Generate blocks from source.
3. Review the Compile log. The most common differences between V5.5 and TIA Portal are:
   • UPPER and LOWER bounds in FB parameter declarations behave differently in TIA Portal (TIA enforces strict typing).
   • Indirect memory addressing (OPN DB[MW0]) requires explicit PEEK/POKE rewrites.
   • SFB/SFC library versions are newer in TIA Portal; FBs that called SFB 0/1/2/3/4/5 in V5.5 will pull the latest versions automatically.
4. Add the KTP700 Basic DP using the same hardware configuration steps as above, but the connection target is now the migrated CPU — no proxy required.

Troubleshooting Matrix

Commissioning Verification Checklist

1. CPU 315-2DP in RUN, SF/BF LEDs off, DC5V on.
2. PROFIBUS DP segment: terminators ON at both ends, OFF on all middle nodes. Slave count matches TIA Portal configuration.
3. KTP700 Basic DP shows root screen within 30 s of power-on.
4. Connection status icon on the panel is solid green (not flashing yellow).
5. Touch a button on the panel; verify in STEP 7 V5.5 (online → monitor/modify) that the corresponding input bit changes.
6. Change a process value in the V5.5 VAT (Variable Table); verify the value updates on the HMI within the configured polling cycle (default 1 s for Basic Panels).
7. Force a PLC STOP from the panel (if configured): the panel should display "Connection to PLC interrupted" and the alarm should be logged in the alarm buffer.

References to Official Siemens Documentation

• Application Example: Combined configuration with WinCC (TIA Portal) and STEP 7 V5.x — Siemens Industry Online Support
• SIMATIC HMI Basic Panels 2nd Generation Operating Manual — DigiKey mirror of Siemens document
• Siemens Industry Online Support — search for "CPU 315-2DP" and "KTP700 Basic DP" for firmware, GSD files, and HSP downloads