SINAMICS DCM 6RA80 to S7-1200 Communication PROFINET and PROFIBUS

1. Overview

Integrating a Siemens SINAMICS DCM (6RA80 series) DC drive with a SIMATIC S7-1200 CPU 1214C requires matching the drive's communication interface to the controller's native PROFINET port or a PROFIBUS expansion module. The 6RA80 chassis ships with a CUD1 (Control Unit Deck 1) that exposes PROFIBUS DP on terminal X126 by default. PROFINET requires a hardware upgrade: the advanced CUD2 deck plus a CBE 20 PROFINET communication board, both ordered as a kit.

This reference covers two field-proven paths for the hardware in question:

• PLC 6ES7 214-1AG40-0XB0 (CPU 1214C DC/DC/DC, FW 4.x, single PROFINET port, no native PROFIBUS)
• DCM 6RA8031-6DV62-0AA0 (approx. 30 A armature rating) and 6RA8018-6DV62-0AA0 (approx. 15 A armature rating)

The minimum engineering effort and lowest hardware cost path is PROFIBUS with the CM 1243-5 master module. The recommended long-term path is PROFINET with the CBE 20 because it gives you parameter access via the drive's standard GSDML and removes the bus-master module from the S7-1200.

2. Hardware Identification and Catalog Numbers

Always confirm the active firmware of the CUD1 before commissioning. Open the drive's STARTER / Startdrive project, read the parameters under r0002 (drive state) and r0018 (firmware version). For PROFINET compatibility, the CUD2 firmware must match the Startdrive device version; mismatch yields fault F08501 on the drive and a "device not found" error in TIA Portal.

3. Communication Path Selection: PROFINET vs PROFIBUS

4. PROFINET Hardware Path — Prerequisites

To bring PROFINET to the DCM, the drive must be re-equipped with CUD2. The CBE 20 board then clips into the back of CUD2. Verify the following before starting the upgrade:

1. The CUD1 currently in the drive has firmware version 4.7 SP3 or higher. If it is older, the SD card image must be upgraded first; otherwise the new CUD2 will refuse to accept the parameter set. Reference the SINAMICS DCM List Manual, section "CUD replacement".
2. Order CUD2 as a kit (6RA8000-0AC00-0AA0) or with factory option -2AA0 if the drive has not yet been built.
3. Order CBE 20 (6SL3055-0AA00-2EB0) separately. The board ships with the appropriate mini-USB/IP67 connector for the drive-side PROFINET port.
4. Insert the original SD card (with the parameter set) from CUD1 into CUD2 after installation. The drive boots from the card, preserving all motor data, encoder calibration, and BICO interconnects.

For the controller side, the S7-1200 1214C already has one PROFINET port on the bottom. The MAC address is printed on the front flap; assign a fixed IP (default assignment: 192.168.0.1/24) before adding the drive to the network. Use a SCALANCE XC-108 or XB-008 unmanaged switch for the segment — no router needed.

5. PROFIBUS Hardware Path — Prerequisites

The PROFIBUS route needs no drive-side change. CUD1 ships with the X126 PROFIBUS DP port (9-pin D-sub) active by default. Order the following:

1. CM 1243-5 DP master module (6GK7 243-5DX30-0XE0). The module plugs onto the left side of the CPU 1214C signal board stack.
2. PROFIBUS DP cable (6XV1830-0EH10, violet). Cut to length, install 9-pin D-sub connectors with built-in terminating resistor at the end of the segment.
3. PROFIBUS address switch on the DCM (accessed via the drive keypad or STARTER parameter P0918). Set both DCM drives to unique addresses — for example P0918 = 4 for 6RA8031 and P0918 = 5 for 6RA8018.

6. TIA Portal — Project and Device Configuration (Common)

The configuration is identical up to the point of inserting the drive's GSD. Open TIA Portal V18 (or the version matching the CPU firmware), then:

1. Create a new project, "Add new device → S7-1200 CPU → 6ES7 214-1AG40-0XB0".
2. Double-click the CPU in the device tree, then "Properties → General → PROFINET interface". Set a fixed IP (e.g., 192.168.0.1) and subnet mask 255.255.255.0. Disable "Obtain IP address from router".
3. Open "Devices & Networks" from the project tree. The network view will show the CPU's PROFINET port at the center.

7. PROFINET Path — Step-by-Step TIA Portal Configuration

1. Install the SINAMICS DCM GSDML. Download the latest package from the Siemens support article for the drive firmware revision (search "SINAMICS DCM GSDML"). Import via "Options → Manage device description files (GSD)" and select the GSDML-Vx.x-Siemens-SINAMICS_DCM-yyyymmdd.xml file. Restart TIA Portal after import.
2. Drag a "SINAMICS DCM" device from the catalog (right pane) into the network view. The catalog path is: "Other field devices → PROFINET IO → Drives → Siemens AG → SINAMICS DCM".
3. Click the PROFINET port of the CPU, then click the PROFINET port of the DCM device. A dashed line appears; click it to assign a PROFINET IO relationship. Alternatively, use drag-and-drop from the CPU port to the DCM port.
4. Assign the DCM a fixed IP, e.g., 192.168.0.10. Set the device name to "dcm-6ra8031". The device name is required for PROFINET IO and must match exactly the name written to the CBE 20 via STARTER/Startdrive (parameter p8920 / p8921 / p8922 / p8923) or the TIA "Assign PROFINET device name" tool.
5. Insert the drive's slot modules: right-click DCM device → "Properties → Device view". Slot 0 is the head module (PZD-2/2 by default). Add additional telegram modules as required by the application: Standard telegram 1 (control word + speed setpoint, status word + actual speed), telegram 3 (setpoint + actual value 16-bit), telegram 999 (free BICO mapping). For closed-loop torque / current control, use Standard telegram 5.
6. Set the PROFINET update time. For a DC drive, 2 ms is appropriate (rated drive cycle is 4 ms). Click the PROFINET IO relationship line, set "Update time = 2.000 ms" and "Watchdog time = 3 × update = 6.000 ms".
7. Compile the project (right-click project → "Compile → Software (rebuild all)"). Correct any errors flagged in the compile log.
8. Download the project to the CPU. Select the CPU → "Online → Download to device". Use the MAC address scan to identify the CPU on the network.

For a closed-loop speed application, the most common configuration is:

• Slot 0: PROFINET head module + Standard telegram 1 (2 PZD out, 2 PZD in)
• Slot 1: SINAMICS DCM PKW (parameter channel, 4 words, optional but recommended for STARTER access over PROFINET)

8. PROFIBUS Path — Step-by-Step TIA Portal Configuration

1. Physically install the CM 1243-5 in the S7-1200 stack. Power cycle the PLC.
2. Detect the new module in the device configuration: click the CPU in the device view, drag "CM 1243-5" from the catalog (Communication modules → PROFIBUS) into slot 101. The module is now represented in the device tree.
3. Open "Devices & Networks". The CM 1243-5 PROFIBUS interface appears under the CPU. Drag the CM 1243-5 PROFIBUS port to the network view.
4. Install the SINAMICS DCM GSD for PROFIBUS. The PROFIBUS GSD is typically named "SIEM80F0.GSD" or similar. Import via "Options → Manage device description files (GSD)".
5. Drag a "SINAMICS DCM" DP slave from the catalog (Other field devices → PROFIBUS DP → Drives → Siemens AG → SINAMICS DCM) into the network view.
6. Connect the CM 1243-5 PROFIBUS port to the DCM DP slave port. The connection is established automatically.
7. Set the PROFIBUS address on the DCM slave to match P0918 on the drive (e.g., 4 for 6RA8031, 5 for 6RA8018). Set the bus baud rate to 1.5 Mbaud (the default and the most stable for 100 m segments with two devices).
8. Configure the slot structure: Slot 0 = head module, slot 1 = PKW (parameter channel), slot 2 = PZD (process data) for the control word and setpoint. Add Standard telegram 1 (2 PZD out, 2 PZD in) as the PZD module.
9. Compile and download the project.

9. Drive-Side Parameter Configuration

For both paths, the drive's process data interface must be wired to the firmware's control words and setpoint sources. The required parameters are summarised below.

The signal source selection in p0927 (or in the modern control word source list) determines which interface has authority. For a PROFINET CBE 20 install, set the fieldbus source to the CBE 20 PROFINET channel; for PROFIBUS, set it to the X126 channel. Refer to the SINAMICS DCM List Manual for the exact source ID for the firmware build installed.

10. PLC-Side Programming

The I/O addresses for the DCM are assigned by TIA Portal in the device view. After compiling, click the DCM slot 0 module to read the assigned I and Q addresses. For Standard telegram 1 on a 6RA8031 at PROFINET address 192.168.0.10, the default mapping is:

// Standard telegram 1 mapping (drive #1)
// Inputs (status from drive):
%IW100  = ZSW1   // Status word 1
%IW102  = NIST_A // Actual speed (16-bit, signed)

// Outputs (control to drive):
%QW100  = STW1   // Control word 1
%QW102  = NSOLL_A // Speed setpoint (16-bit, signed)

A typical control block in Structured Text (SCL):

// FB_DriveControl — section for start/stop and setpoint
// Inputs:  bEnable : BOOL ; rSetpointHz : REAL
// Outputs: bRunning : BOOL ; rActualHz : REAL

IF bEnable THEN
    // Control word bits: ON/OFF1 = 1, OFF2 = 1, OFF3 = 1, Enable = 1, Ramp enable = 1
    wControlWord := 16#047F;
ELSE
    // OFF1 = 0 (controlled ramp-down), OFF2/OFF3 = 1 (no coast, no quick stop)
    wControlWord := 16#047E;
END_IF;

// Convert REAL setpoint in Hz to 16-bit (16384 = 100% motor rated speed)
iSetpoint := REAL_TO_INT(rSetpointHz / 100.0 * 16384.0);

// Write to drive
QW100 := wControlWord;
QW102 := iSetpoint;

// Read status from drive
wStatusWord := IW100;
rActualHz  := INT_TO_REAL(IW102) / 16384.0 * 100.0;
bRunning   := (wStatusWord AND 16#0001) <> 0;  // Bit 0 = "Operation enabled"

For PROFIBUS, the I/Q addresses follow the same pattern. The CM 1243-5 maps the DP slave I/O areas into the PLC's process image at the addresses shown in the device view.

11. Commissioning and Verification

1. Drive first, then PLC. Power the DCM and bring it to the run state without bus connection. Confirm the drive displays a normal "Ready to switch on" status (r0002 = 0x10C for a 6RA80).
2. Connect the bus cable. For PROFINET, verify the CBE 20 LINK LED is solid green; for PROFIBUS, verify the CM 1243-5 status LED is steady green (no flashing red).
3. Online in TIA Portal, open "Online & Diagnostics" on the CPU. The "PROFINET / PROFIBUS" tab should show the drive as reachable and the I/O areas in OP (operator) state.
4. From the PLC's watch table, force the control word to 0x047E (OFF1 = 0) and verify the drive displays "Switching on inhibited". Force the control word to 0x047F and verify the drive ramps up to a small setpoint (e.g., 5%).
5. Monitor the actual speed (IW102) for a stable value within 1–2 % of the setpoint. Check the drive's r0002 state transitions: 0x21C (operation enabled) should appear within 2 seconds of writing 0x047F.
6. Disable the drive (write 0x047E), confirm the drive ramps down to 0, and the bus connection stays online.
7. Capture the drive's fault buffer (r0945 / r0947) to confirm no bus-side faults (F08501, F08502, F01910) appear during the test.

12. Troubleshooting Matrix

13. Alternate Routes and Field Notes

When the drives are located far from the S7-1200 or when the S7-1200 slot budget is already full, a third-party PROFINET/PROFIBUS gateway (e.g., HMS Anybus, Helmholz) can be used. The gateway sits on the PROFINET side of the S7-1200 and exposes a PROFIBUS master port to the drives. This is more expensive than the CM 1243-5 route but does not consume an S7-1200 signal board slot.

For replacement parts, the S7-1200 catalog cross-references confirm 6ES7 214-1AG40-0XB0 is the most current revision as of the project date. Newer firmware updates can be loaded via the SIMATIC Automation Tool or a TIA project download with the CPU in STOP. The PROFINET port on the CPU is dual-purpose (programmer port and IO controller) — for plant network isolation, deploy the project with the CPU in the PROFINET IO role and route the HMI to a separate subnet.

If the S7-1200 must coexist with a SCALANCE switch in a ring topology, the PROFINET route supports MRP (Media Redundancy Protocol) when both the switch and the controller participate. The CM 1243-5 PROFIBUS route does not offer ring redundancy; for redundant PROFIBUS, move to the CM 1243-5 in conjunction with a Y-link or duplicate CM modules — but this is rarely cost-effective for a single-pair drive network.

14. Frequently Asked Questions