Configuring SINAMICS S110 CU305 with PM240-2 in SCOUT

The SINAMICS S110 is a single-axis servo drive from the Siemens SINAMICS family, built around the CU305 Control Unit. Unlike the SINAMICS S120, which uses a multi-axis DC-bus architecture, the S110 is intended for a single servo axis. The S110 typically pairs the CU305 with PM340 power modules in the blocksize format. The PM240-2 power module—originally designed for the SINAMICS G120/G120C drives—can be used with the S110 CU305 PN, but only with the correct firmware and SSP (Support Package) combination. When the wrong combination is installed, the PM240-2 does not appear in the SIMOTION SCOUT device catalog and the project cannot be configured offline. This article documents the compatibility matrix, the SSP that resolves the missing device, and the online commissioning workflow that SCOUT enforces for this combination.

1. Problem Statement: PM240-2 Power Module Not Listed in SCOUT

Engineers commissioning a SINAMICS S110 with PM240-2 frequently encounter the following scenario in SIMOTION SCOUT V4.4.0.6:

• The CU305 PN is added to the SCOUT project.
• The PM240-2 power module is not visible in the device catalog under the S110 V4.4.3 option.
• PM340 also disappears from the catalog after the S110 V4.4 SSP is installed.
• Offline configuration of CU305 PN + PM240-2 is rejected by SCOUT.

This blocks the project before any parameterization can begin. The root cause is not a project bug, but a firmware and toolchain compatibility constraint introduced when the PM240-2 was added to the S110 device family. The fix is to install the matching Support Package (SSP) and to use the online upload workflow that SCOUT enforces for this hardware combination. The official configuration entry is documented in the Siemens Industry Online Support entry 109474890.

2. Root Cause Analysis

The CU305 PN + PM240-2 combination is supported from SINAMICS S110 firmware V4.4 SP3 onward. The required changes are not present in earlier S110 firmware versions (V4.3, V4.4 without SP3, or V4.4.0.x of SCOUT alone). Two specific gaps cause the missing device in SCOUT:

1. Device description (DSD/DD) gap. SCOUT V4.4.0.6 contains the device description files for the PM340 only. The PM240-2 device description is delivered through the S110 V4.4 SP3 SSP. Without the SSP installed, SCOUT has no offline representation of the PM240-2 component and refuses to insert it into the project tree.
2. Offline configuration restriction. Even after the SSP is installed, SCOUT does not allow offline configuration of the CU305 PN + PM240-2 combination. The drive is configured only by performing an online upload of the connected drive's actual configuration into the SCOUT project. The drive's auto-commissioning macro, executed at first power-up, supplies the topology and basic parameters that SCOUT then reads back.

This restriction is by design. The PM240-2 power module is a shared component across the SINAMICS G120, G120C, and S110 platforms. SCOUT (which is a SIMOTION-oriented tool) carries only a subset of the SINAMICS device descriptions. STARTER remains the full-feature commissioning tool for SINAMICS drives and can configure the same combination offline.

3. Affected Hardware, Firmware, and Software Combinations

4. Prerequisites

Before applying the resolution, confirm the following are present at the engineering workstation and on the machine:

• SIMOTION SCOUT V4.4.0.6 (or later V4.4.x) installed.
• SINAMICS S110 SSP 4.4.3 (or matching version) installed, visible in the SCOUT device catalog.
• A valid license for the SCOUT engineering tool.
• Ethernet interface to the CU305 PN (PROFINET) with TCP/IP reachable to the drive's IP address.
• CU305 PN with firmware V4.4 SP3 or higher (verify on the CF card or startup banner).
• PM240-2 power module with the appropriate frame size (FSA, FSB, FSC, FSD, FSE, or FSF) and line voltage class (3AC 400 V or 3AC 230 V variants).
• DRIVE-CLiQ cable between CU305 PN and PM240-2 (the PM240-2 has a DRIVE-CLiQ interface for the CU connection).
• 24 V DC control supply for the CU305 PN at terminal X124, minimum 1 A.
• Line filter for frame sizes FSD–FSF (required to meet EMC class limits per the manual).

5. Step-by-Step Resolution

The resolution has three distinct phases: install the SSP, perform an online upload to populate the project, and verify the configuration. The SSP install fixes the catalog gap; the online upload is the only path SCOUT exposes for this combination.

5.1 Install the S110 V4.4 SP3 SSP

1. Close SCOUT before starting the install to avoid locked files.
2. Run the SSP installer (e.g., SINAMICS_S110_SSP_V4_4_SP3.exe or the equivalent downloaded from the Siemens support portal). The SSP adds the device description (DSD) for the PM240-2 to the SCOUT catalog.
3. Confirm the SSP version in the SCOUT Help → Installed Software menu. The build number must match the S110 firmware on the CU305 PN.
4. Rebuild the SCOUT device catalog if the new entry does not appear immediately.
5. Restart SCOUT to load the new device description.

5.2 Build the SCOUT project (online only)

1. Create a new SIMOTION SCOUT project with the correct DCC version.
2. Add the CU305 PN as the SINAMICS device. Use the V4.4 SP3 catalog entry.
3. Do not attempt to insert the PM240-2 from the offline catalog—this path is blocked by design.
4. Configure the PROFINET device name and IP address on the CU305 PN. The default is 192.168.0.2, but the field installation usually reassigns this.
5. Compile and download the project to the CU305 PN.

5.3 Power up and run the auto-commissioning macro

1. Apply 24 V control voltage to the CU305 PN at terminal X124.
2. Apply line voltage to the PM240-2 power module through the line filter (FSD–FSF) or directly (FSA–FSC).
3. Observe the LED sequence on the CU305. The RDY (Ready) LED flashes green during the startup macro; the auto-commissioning macro executes at first power-up. This macro identifies the connected power module and writes the basic topology to the drive.
4. Wait until the CU305 reports a stable operating state: RDY LED solid green, no active fault on the SF LED, and the drive's parameter view shows the PM240-2 as the recognized power section.

5.4 Upload the configuration from the drive

1. In SCOUT, right-click the SINAMICS device → Target system → Upload device configuration to PG (or the equivalent "Upload to project" function in your SCOUT build).
2. SCOUT reads the actual topology, motor data, and power module identification from the CU305 and updates the project tree with the PM240-2 entry.
3. If the install is corrupted, the upload produces explicit error messages. A clean upload completes without errors and the PM240-2 appears as a child of the CU305 in the project tree.
4. Save the project to commit the uploaded configuration.

6. Online Commissioning Workflow

The online upload is not a one-time step; it is the central workflow for any S110 + PM240-2 project in SCOUT. The general flow is:

The diagram above shows the practical sequence: SCOUT establishes PROFINET to the CU305 PN, which executes the auto-commissioning macro on first power-up. The macro identifies the PM240-2 and writes the topology. SCOUT then performs the upload and inserts the PM240-2 into the project tree. From this point, the drive is parameterizable: motor data, encoder selection, current/voltage limits, ramp-function generator, and (if equipped) safety functions.

7. DRIVE-CLiQ Topology and Topology Rules

The PM240-2 power module connects to the CU305 PN through the DRIVE-CLiQ interface. The PM240-2 has a single DRIVE-CLiQ port labelled X200 on the front of the unit, which is wired directly to the CU305 PN port X100 or X101 with a shielded DRIVE-CLiQ cable. The CU305 has two DRIVE-CLiQ ports to support an optional Sensor Module (SMC) for external encoders.

Topology rules for the S110 with PM240-2:

• One CU305 per drive line-up. The S110 is a single-axis platform; a second CU305 is not supported.
• One PM240-2 per CU305. The PM240-2 is a blocksize unit that forms the entire power section. No DC-bus coupling to additional modules.
• Sensor Modules (SMC) are optional. An external encoder can be connected through an SMC10, SMC20, or SMC30 if the application requires it. The CU305 also has built-in encoder interfaces for incremental (TTL/HTL) and absolute (SSI) encoders, so SMC is only required for sin/cos (EnDat) or SSI encoders with specific protocols.
• Line filter and line reactor. PM240-2 frame sizes FSD–FSF require a line filter to meet EMC limits. The line filter connects between the line supply and the PM240-2 line input, with no DRIVE-CLiQ connection to the CU.
• Braking resistor. For frame sizes FSD–FSF, an external braking resistor is typically required for regenerative operation. The braking resistor is wired to terminals R1 and R2 on the PM240-2 and configured via parameters p0219, p0220, p0221 (braking resistor data).

8. Configuration Limits and Operating Modes

The S110 supports several operating modes once the PM240-2 has been uploaded into the SCOUT project. Select the mode via p1300:

For each operating mode, configure the ramp-function generator (p1120 ramp-up, p1121 ramp-down), the current and speed limits (p0640 current limit, p1082 maximum speed), and the encoder interface parameters (p0400 series for encoder selection, p0430 series for encoder configuration). The torque limit is split into motor-mode and generator-mode limits (p1520, p1521) and a regenerative-side limit (p1523, p1524).

Key parameters to verify after the upload:

• r0203 – power module order number (read-only, should match the physical PM240-2 MLFB).
• r0204 – power module firmware version.
• p0201 – power module code (used when swapping PM240-2 units of different ratings).
• r0206 – rated power module current.
• r0061 – speed actual value (used to confirm encoder direction sign).

9. Alternative: Commissioning with STARTER V4.4

If offline configuration of the CU305 + PM240-2 is mandatory, switch to STARTER V4.4 (or the matching version that supports S110 V4.4 SP3). STARTER is the dedicated commissioning tool for SINAMICS drives. It carries the full device catalog for the S110 platform and supports the PM240-2 offline as well as online.

1. Install STARTER V4.4 on the engineering workstation.
2. Create a new project, insert a SINAMICS S110 device, and select CU305 PN.
3. Insert the PM240-2 power module offline from the catalog (FSA through FSF depending on the field hardware).
4. Configure the drive parameters offline: motor data, encoder selection, current/voltage limits, ramp-function generator, and PROFIsafe configuration if used.
5. Set the PROFINET device name and IP address, then go online and download the project to the CU305.

STARTER and SCOUT can coexist on the same engineering workstation. They both target the same CU305 firmware; the only difference is the toolchain and the project file format. Many large machine builders use SCOUT for SIMOTION program development and STARTER for SINAMICS drive commissioning, then download the final drive configuration from STARTER and the SIMOTION program from SCOUT into the same CU305 PN.

10. Verification and Acceptance Test

After the upload completes, perform the following verification sequence before releasing the drive for production:

1. Device tree check. In SCOUT, expand the SINAMICS device. The PM240-2 must appear as a child of the CU305 with the correct order number (MLFB) and the correct frame size (FSA, FSB, FSC, FSD, FSE, FSF).
2. Parameter view. Open the parameter view of the PM240-2 and verify the rated data: r0203 (power module order number), r0204 (power module firmware version), p0201 (power module code), and r0206 (rated power module current).
3. Topology check. The DRIVE-CLiQ topology diagnostic screen (accessible via Diagnostics → Topology) must show a direct CU305 → PM240-2 link with the correct component numbers and no topology errors.
4. Motor identification. Run the motor identification routine (p1910 = 1, then p1900 = 2) to populate the motor equivalent circuit data. This is mandatory when the motor is connected to the PM240-2 for the first time. The drive runs a brief self-energized test; the motor shaft may move by a small angle.
5. Speed encoder check. Verify the encoder pulses (p0408) and the encoder mounting direction (p0410) match the actual machine. Move the axis by hand and confirm the direction sign in r0061 (speed actual value) is positive in the defined positive direction.
6. Current limit check. Set a conservative current limit (e.g., p0640 = 50 % of rated) for the first test moves; raise to full rating only after the motion profile is verified.
7. Safety function test (if STO is wired). For PM240-2 frame sizes FSD, FSE, FSF, the STO function supports PL e per EN ISO 13849-1. Trigger STO via the safe input terminals or PROFIsafe and verify the drive coasts to a stop and reports the safe state. The acceptance test must follow EN ISO 13849-2 or IEC 62061 as applicable.

11. Troubleshooting Matrix

FAQ