Migrating Siemens S5 CP1430 Sinec H1 to S7-400 CP443-1: Step-by-Step

This technical reference documents the field-proven procedure for replacing a Siemens S5-135 CP 1430 TF module and its Sinec H1 (Industrial Ethernet) infrastructure with an S7-400 CPU and a CP 443-1 communications processor. The guide covers physical layer conversion (thick coax / AUI to twisted pair), ISO transport connection re-creation in NetPro, FETCH/WRITE mode mapping, and WinCC v7.0 tag migration from the S5 Ethernet Layer (S5-L4) driver to the S7-TCPIP suite.

1. Migration Scope and Topology Assumptions

The reference migration replaces the following S5-side hardware:

• S5-135U / S5-155U CPU with a CP 1430 TF communications module (Siemens article numbers 6GK1143-0BA01 / 6GK1143-0BA02) configured for Sinec H1 (Industrial Ethernet IEEE 802.3, 10 Mbit/s).
• A 10BASE5 (yellow cable) or 10BASE2 (thin coax / "brown cable") Sinec H1 backbone terminated with repeaters and transceiver drops.
• A PC-based WinCC v7.0 station using a CP 1613 (6GK1161-3AA01) PCIe/ISA card with the WinCC S5 Ethernet Layer driver ("S5-L4").
• Multiple peer S5-135/155 stations using the same Sinec H1 bus for cross-CPU data exchange.

The replacement hardware is an S7-400 station (CPU 414/416/417) with a CP 443-1 (6GK7443-1EX11-0XE0, -1GX11-0XE0, or the 4-port variant 6GK7443-1UX11-0XE0). All migration decisions described below assume the existing Sinec H1 bus is being preserved during cut-over to avoid interruption of the peer S5 CPUs. Refer to the STEP 7 From S5 to S7 Conversion Manual for the broader S5 program conversion workflow that runs in parallel with this communications migration.

2. Sinec H1 vs Industrial Ethernet: Physical Layer Constraints

Sinec H1 is the historical Siemens name for IEEE 802.3 10 Mbit/s Industrial Ethernet using ISO transport services (RFC 1006 on top of TCP, plus the connection-oriented ISO-on-TCP variant). The physical media in the legacy plant is typically one of the following:

The CP 1430 TF exposes an AUI (Attachment Unit Interface, 15-pin D-Sub) port for the host CPU's external MAU (transceiver). The CP 443-1 exposes an RJ45 port. When the legacy Sinec H1 backbone uses 10BASE5 (yellow) or 10BASE2 (brown) cabling, the engineer must either replace the segment with twisted-pair Industrial Ethernet or insert a media converter. Replacing the backbone is faster and more reliable; preserving the legacy coax is acceptable when trenching or cable tray access is restricted.

3. Media Conversion Options: AUI-to-Twisted-Pair Bridges

Two viable approaches bridge an AUI DTE port onto a 100 Mbit/s twisted-pair switch:

3.1 Industrial Media Converter (Preferred for Field Use)

A DIN-rail mounted media converter with an AUI input and one or more RJ45 outputs lets the CP 1430 slot continue to communicate on the new bus without rewiring the segment. Examples include third-party AUI-to-UTP converters (Black Box LE180A-class devices) installed in the cabinet alongside the existing CP 1430. This option is recommended when the existing Sinec H1 segment must remain operational for peer S5 stations that are not being replaced at the same time.

3.2 Replace the Segment with a Scalance X Managed Switch

For a permanent migration, replace the legacy 10BASE5/10BASE2 backbone with a Scalance X-series Industrial Ethernet switch (e.g., Scalance X101 / XC100 / XC200) and run twisted-pair drops to each station. The repeaters previously used for Sinec H1 are decommissioned. The Scalance X101 supports 10/100 Mbit/s auto-negotiation and auto-crossover (MDI/MDIX), which simplifies drop cable wiring. The resulting bus operates at 100 Mbit/s, but the S5 peer stations continue to communicate using ISO transport at the protocol layer, which is fully compatible.

4. Selecting the CP 443-1 Variant

For a typical Sinec H1 replacement with 4-12 peer connections, the EX11 or GX11 variant is sufficient. For larger plants with many cross-CPU data exchanges, the UX11 4-port variant is preferred because it eliminates the need for an external switch at the rack and supports connection counts well above the S5 peer list.

Verify the installed STEP 7 version supports the CP firmware. SIMATIC Manager V5.5 SPx or TIA Portal V13+ is required for the V3/V4 firmware variants. Mismatched CP firmware and STEP 7 component version is a common cause of "Connection not established" errors after migration.

5. Documenting Existing CP 1430 Connections with NCM COM 1430

Before removing any S5 hardware, extract every configured connection from each CP 1430 TF. The dedicated tool for this on the S5 side is NCM COM 1430 (Siemens part of the COM 1430 TF software package). Use it to read each CP's connection database and export:

• Ethernet MAC address of the local CP 1430.
• Connection type for each entry (SEND/RECEIVE, FETCH active/passive, WRITE active/passive).
• Partner MAC address and partner TSAP (Transport Service Access Point) for each remote station.
• Local TSAP (typically encoded with the rack/slot and connection number in S5 format).
• Data block references and length for SEND/RECEIVE.
• Cycle / timeout parameters.

Save the export as the master record. The same TSAPs and MAC addresses are re-entered into NetPro on the S7-400 side to keep the partner S5 stations from needing any modification at all.

6. Connection Type Mapping: S5 Active/Passive vs S7 Equivalents

The CP 1430 supports four connection roles. The CP 443-1 supports a superset, but the role pairing must be preserved or the partner CPU will reject the connection. The mapping is:

7. TSAP and MAC Address Handling

TSAPs on the S5 side are typically 2-byte hex values such as 01.01 (rack 0, slot 1 in COM 1430 notation), 02.05, or symbolic values such as S5-CPU1. The CP 443-1 accepts TSAPs in either numeric or ASCII form via NetPro. To minimise disruption on the partner S5 stations, keep the numeric TSAP strings identical. Example mapping:

Legacy CP 1430 entry:
  Local TSAP    : 01.01
  Partner MAC   : 08.00.06.01.02.03
  Partner TSAP  : 02.01
  Connection type: SEND/RECEIVE

NetPro entry on S7-400 CP 443-1:
  Local TSAP    : 01.01     (identical)
  Partner MAC   : 08.00.06.01.02.03   (identical)
  Partner TSAP  : 02.01     (identical)
  Connection type: ISO transport, SEND/RECEIVE

MAC addresses on the new CP 443-1 are assigned via the CP's DIP switches or via STEP 7 / TIA Portal hardware configuration. If the existing CP 1430 MAC address must be preserved on the bus (for example, because a partner CPU is hard-coded to that MAC), the CP 443-1 should be assigned the same MAC. CP 443-1 supports manual MAC override in the hardware properties.

8. NetPro Configuration on the S7-400

Open the S7 project in SIMATIC Manager (or TIA Portal), open the S7-400 station, and add the CP 443-1 to the hardware configuration at the slot corresponding to the position previously occupied by the CP 1430 (or any free slot in the rack that the STEP 7 hardware catalog allows for that CPU type). Then open NetPro (or "Devices & Networks" in TIA Portal) and create an ISO transport connection for each entry from the NCM COM 1430 export.

1. Right-click the CP 443-1 in NetPro and choose Insert New Connection.
2. Select Unspecified as the partner and pick ISO transport connection as the type.
3. Enter the partner MAC address exactly as recorded from the CP 1430 export.
4. Enter the local and partner TSAPs exactly as recorded.
5. Select the role: SEND/RECEIVE, FETCH passive, or WRITE passive according to the table in section 6.
6. Confirm the connection ID and slot. The S7-400 connection ID is a 16-bit word used by the program blocks (e.g., ID = W#16#0001).
7. Download the hardware configuration and the NetPro connection table to the S7-400 CPU. The CP 443-1 firmware boots with the new connection database.

9. SEND/RECEIVE Programming on the S7-400

Each ISO transport connection is consumed from the user program by an FC/FB that matches the role:

• FC5 / FC50 (AG_SEND) and FC6 / FC60 (AG_RECV) for SEND/RECEIVE role on ISO transport.
• FB7 (FETCH) and FB8 (WRITE) when CP 443-1 is active (rare for a migrated station because the legacy was likely the active partner).
• FB9 (FETCH passive server) and FB10 (WRITE passive server) when CP 443-1 is passive — the partner CPU initiates FETCH/WRITE.

A minimal S7-400 SEND example:

CALL "AG_SEND"  // FC5
   ACT     := TRUE
   ID      := W#16#0001          // NetPro connection ID
   LADDR   := W#16#0100          // CP 443-1 logical base address
   SEND    := P#DB100.DBX0.0 BYTE 200
   LEN     := 200
   DONE    := M10.0
   ERROR   := M10.1
   STATUS  := MW12
   NOP     := 0;

A minimal S7-400 RECEIVE example:

CALL "AG_RECV"  // FC6
   ID      := W#16#0001
   LADDR   := W#16#0100
   RECV    := P#DB110.DBX0.0 BYTE 200
   NDR     := M20.0
   ERROR   := M20.1
   STATUS  := MW22
   LEN     := MW24
   NOP     := 0;

Both blocks use the same ID as the connection row in NetPro and the logical base address LADDR from the CP 443-1 hardware configuration. Mismatched ID or LADDR yields STATUS = 0x8181 (connection not configured) or 0x8183 (partner not reachable).

10. WinCC v7.0 Tag Migration: S5-L4 → S7-TCPIP

The PC-based WinCC v7.0 station must migrate from the legacy S5 Ethernet Layer driver ("S5-L4", tied to the CP 1613 and Sinec H1) to the S7-TCPIP channel that ships with every WinCC v7.0 installation. The tag database is rewritten; the wire-level protocol is the same ISO transport, so the WinCC side simply needs new driver entries and updated tag addresses.

10.1 Add the S7-TCPIP Channel

1. In WinCC Explorer, right-click Tag Management → Add New Driver → select SIMATIC S7 PROTOCOL SUITE → TCP/IP.
2. Right-click TCP/IP → System Parameters and configure the unit IP address, rack, and slot of the S7-400 CPU.
3. Disable or remove the legacy S5 Ethernet Layer driver once the new tags are online.

10.2 Address Conversion: S5 → S7 Format

WinCC S5-L4 tags use data block / word / bit notation tied to S5 absolute addressing (e.g., DB 100 DW 0). The S7-TCPIP driver uses S7-conformant addressing (DB100.DBD0, DB100.DBW0, DB100.DBX0.0). Use the WinCC tag export to a CSV and rewrite the address column. A typical conversion:

11. End-to-End Migration Procedure

1. Inventory: Document all CP 1430 connections with NCM COM 1430. Record MAC, TSAP, role, DB references.
2. Topology: Decide whether to replace the Sinec H1 backbone or insert AUI-to-UTP media converters. For permanent migration, replace with a Scalance X switch.
3. Hardware prep: Install the S7-400 rack, CPU, and CP 443-1 alongside the existing S5 rack. Power up. Assign an IP/MAC address on the same subnet (or none, if ISO-only).
4. Configure CP 443-1: In STEP 7 / TIA Portal, add the CP 443-1 in the hardware config, set its MAC address to match the legacy CP 1430 (if MAC preservation is required), set the IP/subnet (for diagnostics).
5. Recreate connections in NetPro: For each CP 1430 entry, create a matching ISO transport connection on the CP 443-1, copying MAC and TSAP values.
6. Download to S7-400: Download hardware config and NetPro to the CPU. The CP 443-1 will start to listen on the listed TSAPs.
7. Program SEND/RECV: Add FC5/FC6 calls in the OB1 cycle with the correct ID and LADDR.
8. Migrate WinCC tags: Add the S7-TCPIP driver, configure the unit, convert tag addresses, set byte order, and remove the S5-L4 driver.
9. Parallel run: Keep both racks powered. Verify that the S5 partner CPUs and the WinCC station are receiving identical data from the new S7-400 as from the legacy CP 1430.
10. Cut-over: After the agreed soak period (typically 24-72 hours), decommission the CP 1430 and remove the legacy S5-135 rack from the bus.

12. Verification and Commissioning Checklist

13. Troubleshooting Matrix

14. Reference Documents and Tools

• STEP 7 From S5 to S7 Conversion Manual — Siemens Industry Online Support, document number 45531547.
• CP 443-1 manual entry on Siemens Industry Online Support: search for "6GK7443-1EX11" or "CP 443-1 Operating Instructions" for the full connection ID / status code reference.
• STEP 7 / SIMATIC Manager online help: Communication > Industrial Ethernet > ISO Transport Connections.
• WinCC Information System: Communication > S7-TCPIP Channel > Configuring the Unit.

15. Field Notes and Common Pitfalls

• Preserving the legacy MAC address on the new CP 443-1 is sometimes the only way to avoid reconfiguring dozens of partner S5 stations. Use the CP 443-1 hardware property "MAC address" to set it manually.
• The CP 443-1 supports both ISO transport and ISO-on-TCP. The legacy CP 1430 only uses ISO transport. Use ISO transport for full protocol compatibility; ISO-on-TCP will be rejected by the CP 1430.
• CPU 416 / 417 with multiple CPs may exceed the maximum number of simultaneously active ISO connections per CP. Verify the firmware release notes for the chosen CP 443-1 firmware version.
• If the plant later upgrades WinCC to v7.4 or v7.5, the S7-TCPIP channel name and configuration dialog changes but the underlying ISO transport stays the same; tag addresses do not need re-entry.
• Document every tag, DB reference, and TSAP in a migration register. The single most time-consuming part of any S5-to-S7 migration is reconstructing undocumented tag names after the S5 program has been archived.