Connecting SINAMICS G150 to PC with STARTER: Commissioning Guide

Overview

The SINAMICS G150 is a Siemens air-cooled, cabinet-style low-voltage drive based on the SINAMICS S120 platform. It is designed for single-motor applications in the power range of 75 kW to 2700 kW (depending on the line voltage and cooling configuration). The drive is controlled by a CU320 or CU320-2 Control Unit that hosts the drive firmware, the parameter set, and the communication interfaces.

For service, diagnostics, and parameterization, Siemens provides the STARTER commissioning tool (later superseded by SINAMICS Startdrive in the TIA Portal). To bring the drive online, the engineer must select the correct physical interface, install the matching Support Package (SSP), set the correct protocol parameters (PROFIBUS address or Ethernet IP), and confirm firmware compatibility with the installed STARTER version.

This article covers the three most common paths for connecting a G150 (and the closely related S120) to a PC:

1. Service interface X127 (point-to-point Ethernet, recommended for commissioning)
2. PROFINET interface X150 with a CBE20 Communication Board (Option G33)
3. PROFIBUS interface X126 on the CU320-2 DP variant

It also clarifies why a PROFIBUS-to-RS232-to-USB chain is normally the wrong choice, how to identify the firmware version on the CF card, and how to recover from a PG/PC interface error when STARTER 4.5 is run on Windows 10.

Prerequisites

Before you start, gather the following hardware and software:

Identify the Control Unit and Firmware

Before you can pick a cable and a STARTER version, you must identify two things on the installed drive:

1. Control Unit variant — CU320 (legacy), CU320-2 DP, or CU320-2 PN.
2. Firmware version — the FW version is stored on the CF card; the same CF card label (or the Drive → Version overview page once online) shows a string such as V4.8.5, V5.2 SP3, or V6.0.

To read the CF card label:

1. Open the cabinet door with the line supply isolated and locked out.
2. Locate the CU320/CU320-2 module on the cabinet door; the CF card slot is on the front of the unit.
3. Push the eject button and remove the card. The label on the rear shows the order number and the firmware version, e.g. 6SL3054-0AA01-1AA0 / V4.7 SP6.
4. Re-insert the card before re-energizing.

Record the firmware version. It determines which Support Package (SSP) you must install inside STARTER. The current list is published on the Siemens Industry Online Support portal at support.industry.siemens.com under the entry for STARTER & SINAMICS Support Packages.

Interface and Cable Selection

The selection of cable depends entirely on which physical port you intend to use. The table below summarises the four physical interfaces on a CU320-2:

Why a PROFIBUS → RS232 → USB converter is the wrong choice

A PROFIBUS segment is an RS485 differential bus running at 9.6 kbit/s up to 12 Mbit/s, terminated at both ends, and is not addressable from a USB host without a PROFIBUS master (CP 5611 / CP 5711 / CP 5621) or a PROFIBUS-to-TCP gateway such as the Siemens PN/PN Coupler family or a third-party gateway. A passive RS232 converter cannot interpret PROFIBUS telegrams and will not enumerate as a PG/PC interface in STARTER. If the goal is pure point-to-point engineering, use the X127 service port and a plain Ethernet cable.

Recommended method: connect to X127 (service port)

For first commissioning of a standalone G150, the X127 service interface is the simplest path. It is a fixed-IP interface that does not require a DHCP server:

Configure the PC's network adapter to a free address in the same /16 subnet, e.g. 169.254.11.10, mask 255.255.0.0, no gateway. The X127 port is on the CU320-2 itself; on a CU320-2 PN the port is labelled X127 P1 / X127 P2 for internal switch.

Install STARTER and Support Packages

STARTER V5.1 SP1 or higher is required for Windows 10 support. The standalone version is delivered as STARTER_V5_6_xxx.exe (or older point releases). Modern projects should use SINAMICS Startdrive inside the TIA Portal (V15 and later) for any new G150 work, but STARTER remains fully supported for the S120/G150 firmware family up to V5.4.

1. Install STARTER with administrative rights; on Windows 10/11 the installer must be run as Administrator and any antivirus must allow the STARTER.exe process to open a TCP listener on port 5015 (default) and 49152/TCP for OPC.
2. Launch STARTER and open Help → Installed Software. Confirm the SINAMICS S120 support package is present and matches the G150 firmware. If a higher firmware SSP is missing, STARTER will report "No online connection — device description not found".
3. Download the matching SSP from the Siemens Industry Online Support portal. The naming convention is SSP_SINAMICS_S120_Vxxxx.zip matching the drive firmware (V4.7 → SSP V4.7, V5.2 → SSP V5.2 SP3, etc.).
4. Install the SSP from Options → Install Support Packages. Restart STARTER when prompted.

Create the Project and Insert the Drive

1. Launch STARTER and choose New Project. Save it locally on the PC disk; network drives are not recommended because STARTER writes lock files.
2. From the project tree, right-click the drive icon and select Insert SINAMICS G150. In the Insert Single Drive Unit wizard, pick the device version that matches the order number visible on the cabinet nameplate (e.g. 6SL3710-1LE32-1AA0 for a 110 kW / 400 V unit). The order number encodes the rated power, voltage class, and option list.
3. If the firmware on the CF card is newer than the version bundled in the SSP, STARTER will offer to upgrade the device description at this point. Accept the upgrade only if the new firmware is supported on the cabinet hardware revision; otherwise the upgrade will brick the unit.
4. Open Set PG/PC Interface from the project tree. Select the Ethernet adapter you have connected to X127 and assign the S7ONLINE access point to it. The default access point for service is S7ONLINE (STEP7) → TCP/IP.

Establish the Online Connection

1. Right-click the drive and select Connect to target system → Online. The first handshake performs a wink command — the green READY LED on the CU320 blinks rapidly. If it does not wink, the connection failed at the TCP layer.
2. Once online, the bottom status bar shows Online — running and the drives tree turns yellow.
3. Open Drive → Version overview and confirm the FW version matches the one printed on the CF card. If it does not, you are looking at the wrong drive in the project or the CF card was swapped after the cabinet was energised.
4. Use Load to PG to upload the current parameter set from the drive into the STARTER project. The upload typically takes 30–120 s for a fully-parameterised G150.

Set the Ethernet IP for X150 (PROFINET)

If the drive is integrated into a PROFINET controller network, you must also configure the X150 interface. By default the IP on X150 is 0.0.0.0 — no address is assigned. The IP is set either by the PROFINET controller during device startup, or manually from STARTER:

1. Open Communication → PROFINET interface on the drive tree.
2. Set Device name (e.g. g150-cab-001), IP address (e.g. 192.168.1.108), and Subnet mask (e.g. 255.255.255.0).
3. Click Assign IP via the controller or use Online → Accessible nodes to push the address to the drive.
4. Save with Copy RAM to ROM so the address survives a power cycle.

Set the PROFIBUS address on X126

If the drive is a PROFIBUS DP slave on a SIMATIC controller, the PROFIBUS node address must be unique on the segment and is set as follows:

1. Locate the DIP switches on the CU320-2 DP (a rotary switch on the front of the module) — the high digit is the upper switch, the low digit is the lower switch. Valid range is 1 to 126; 0 = master.
2. Set the rotary switches to the desired address, e.g. 04.
3. Alternatively, the address can be written via parameter p0918 in the drive expert list. The parameter must then be saved to the CF card with Copy RAM to ROM.
4. Re-energise the control electronics so the new address is read at boot. Cycle the 24 V supply to the CU320 if the rotary switches were changed while the unit was live.

Verification

After going online, run the following checks to confirm a healthy installation before any motor is connected:

Troubleshooting Matrix

Field-Commissioning Notes and Edge Cases

The following points are not always obvious from the manual and have caused repeated service calls on SINAMICS G150 cabinets:

• Multiple service laptops on the same cabinet: only one PC can hold a productive online connection to X127 at a time. STARTER will silently close the first connection when a second STARTER instance opens an online link.
• Empty project vs. existing project: if the drive has been commissioned previously and the STARTER project on the laptop does not match the parameters on the CF card, an Upload from drive is safer than a Download to drive. The latter will overwrite the running parameter set.
• Encrypted CF cards (V5.2 SP3 and later): SINAMICS S120/G150 V5.2 SP3 introduced a 4-byte license key on the CF card. STARTER will prompt for the password when first going online; the default OEM password is on the project documentation supplied with the cabinet.
• Firmware downgrade risk: downgrading firmware from V5.x to V4.x wipes the parameter set and can render the drive inoperable on a CU320-2 if the hardware revision does not support the older FW. Always check the release notes in the SSP ZIP before changing firmware.
• PROFINET name assignment: an unconfigured PROFINET device in a controller network will not respond to its IP until a PROFINET name is written by the controller. Use Online → Accessible nodes → Edit PROFINET device name if the controller is not online yet.
• Service interface X127 on CU320-2 PN: although the label looks identical to a PROFINET port, X127 is a fixed-IP service interface and is never used for cyclic PROFINET communication. Connecting it to the plant network will not pass process data.
• USB-to-serial adapters on RS232 X140: the legacy X140 RS232 port is supported only on firmware V4.4 and older. On V4.7+ the interface is hidden by default. Use X127 instead.

Migration to SINAMICS Startdrive (TIA Portal)

For new projects, Siemens recommends migrating commissioning to SINAMICS Startdrive inside the TIA Portal. The migration preserves the parameter set (exported as a .par file from STARTER, then imported into Startdrive) and adds the benefit of integrated PLC and HMI engineering. The IP and PROFIBUS rules above are unchanged — X127 is still 169.254.11.22 and X150 still defaults to 0.0.0.0.

Use Startdrive V15.1 or later for G150 firmware V5.2 SP3 and later; use V14 SP1 for older firmware. The full compatibility matrix is included in the TIA Portal installation README.

Frequently Asked Questions