S7-1200 to SINAMICS G120 PROFINET Communication Setup Guide

1. Overview

This guide describes how to establish PROFINET communication between a SIMATIC S7-1200 controller and a SINAMICS G120 frequency inverter (Control Unit CU240E-2 PN) inside TIA Portal V13 SP1. The configuration uses the PROFINET standard with PROFIdrive application telegrams, a Startdrive-integrated device proxy, and a SIMATIC S7-1200 Motion Control technology object (TO) that maps directly to the drive.

PROFINET is the open Industrial Ethernet standard from PROFIBUS Nutzerorganisation (PNO), and PROFIdrive is the drive profile on top of PROFINET defined in IEC 61800-7. Together they replace the old point-to-point wiring of control words, status words, and setpoint words with cyclic, real-time I/O data exchanged through configurable standard telegrams.

Reference material:

• Siemens PROFINET product page
• PROFINET background (general reference)
• Siemens DriveLib for S7-1200/S7-1500 - application description
• SINAMICS G120 with SIMATIC S7-1200 via PROFINET - application example

2. Prerequisites

3. Architecture and Communication Model

The S7-1200 acts as the PROFINET IO Controller, the G120 as the PROFINET IO Device. Cyclic data is exchanged through PROFIdrive standard telegrams - predefined slot assignments that the controller writes (setpoints) and reads (actual values) every PROFINET cycle. Non-cyclic acyclic communication is used for parameter read/write through the PROFINET record-data channel (used by STARTER/SINAMICS Startdrive commissioning tools).

For G120 with firmware V4.7 the available PROFIdrive telegrams are:

STW1 = Control Word 1 (bit-coded drive commands: OFF1, OFF2, OFF3, Enable, Enable Ramp Generator, Enable Setpoint, Fault Acknowledge, Jog 1/2, etc.). ZSW1 = Status Word 1. NSOLL_A = Speed setpoint (16-bit, signed, normalized to 4000 hex = 100% of p2000). NIST_A = Speed actual (16-bit, normalized the same way). KPC and r61 are optional position-related values for later expansions.

The data is exchanged cyclically by the PROFINET IRT/RT controller; the S7-1200 Motion Control technology object abstracts the STW1/ZSW1 bit manipulations and exposes high-level commands (MC_Power, MC_MoveVelocity, MC_Stop, MC_Reset).

4. Installing Startdrive and the G120 HSP

1. Run the TIA Portal V13 SP1 installer and ensure Step 7 Professional is selected.
2. Install Startdrive V13 SP1 - this is a separate setup that adds the SINAMICS G110M/G120/G120C/G120D/G120P/G130/G150/S120 device families to the TIA hardware catalog.
3. Download the matching Hardware Support Package (HSP) for the G120 firmware level you are using. For FW V4.7 the corresponding HSP is shipped with Startdrive V13 SP1 Update 9 or higher. The HSP adds the exact MLFB / firmware combination to the catalog.
4. Open TIA Portal, choose Options > Support Packages and install the downloaded HSP. Restart TIA Portal.
5. Verify in the hardware catalog under Drives & Starter Kits > SINAMICS Drives > SINAMICS G120 that your CU240E-2 PN variant appears.

5. Hardware Configuration in TIA Portal V13 SP1

1. Create a new project, then Add new device > SIMATIC S7-1200 > CPU 1214C DC/DC/DC (or the exact CPU ordered).
2. Open Device view of the CPU. Under Properties > PROFINET interface, set the IP address (default 192.168.0.1), subnet mask (255.255.255.0), and the device name of the CPU ("plc1200").
3. From the hardware catalog, navigate to Drives > SINAMICS G120 > Control Units > CU240E-2 PN and drag the CU into the Network view. TIA auto-creates a PROFINET IO system and links the CPU PROFINET port to the G120 port 1.
4. Assign the G120 an IP address (e.g. 192.168.0.20) and PROFINET device name ("g120drive") in the device properties of the CU.
5. For multi-port S7-1200 CPUs, the second PROFINET port can be used directly. For single-port CPUs, connect both the CPU and the drive to a PROFINET switch; do not daisy-chain a single-port CPU to the drive.
6. Insert a Power Module (PM240-2) into the same device view. The Power Module is selected from the catalog slot list and determines the inverter current rating. The PM selection feeds the drive parameters p305, p0201, r0200 and the bico interconnects.
7. Insert an optional Operator Panel (BOP-2 or IOP-2) and/or an I/O Extension Module (e.g. for safety or extended digital I/O) if hardware is present.

6. Telegram Configuration on the G120

1. Select the G120 in the network or device view. Open Properties > PROFINET interface > Telegram configuration.
2. From the dropdown, add the desired standard telegram. For speed-axis motion control, choose Telegram 1 or Telegram 20 (Telegram 20 is the Siemens default and matches what the S7-1200 TO expects).
3. The slot assignment becomes:

4. Save and compile the project. The G120's telegram mapping is downloaded with the rest of the project on the next "Download to device" operation.

7. S7-1200 Technology Object (TO) - Speed Axis

1. In the project tree, expand the S7-1200 CPU node. Add new object > Motion Control > Technology object > TO_SpeedAxis.
2. Assign the TO to the G120 PROFINET telegram by selecting "Drive connected via PROFINET". Pick the G120 device and the configured telegram.
3. Configure the axis parameters:

4. Compile and download the hardware configuration. The TO configuration is downloaded together with the S7-1200 program.

8. Motion Control Programming (Ladder)

The S7-1200 Motion Control instruction library is part of the standard TIA Portal install. You do not need a separate library; the blocks live in the Instructions > Motion Control palette. The same blocks can be dropped in Ladder, FBD, or SCL; Ladder is the most common for commissioning.

8.1 Block summary

8.2 Minimal Ladder example

// Network 1: Power the drive
CAL "MC_Power_DB"(
  Axis       := "TO_SpeedAxis_1",
  Enable     := "tagEnable",
  StartMode  := 1,                // 1 = absolute, axis starts at current speed
  StopMode   := 0                 // 0 = ramp stop
);

// Network 2: Reset faults
CAL "MC_Reset_DB"(
  Axis    := "TO_SpeedAxis_1",
  Execute := "tagReset",
  Restart := FALSE
);

// Network 3: Forward run (positive velocity)
CAL "MC_MoveVelocity_DB"(
  Axis        := "TO_SpeedAxis_1",
  Execute     := "tagFwd",
  Velocity    := 1500.0,          // rpm, within p2000 reference
  Acceleration:= 100.0,           // rpm/s
  Jerk        := 0.0,             // 0 = no jerk limit
  Direction   := 1                // 1 = positive, 2 = negative, 3 = current
);

// Network 4: Reverse run (negative velocity)
CAL "MC_MoveVelocity_DB"(
  Axis        := "TO_SpeedAxis_1",
  Execute     := "tagRev",
  Velocity    := 1500.0,
  Acceleration:= 100.0,
  Jerk        := 0.0,
  Direction   := 2
);

// Network 5: Stop
CAL "MC_Halt_DB"(
  Axis        := "TO_SpeedAxis_1",
  Execute     := "tagStop",
  Deceleration:= 100.0,
  Jerk        := 0.0
);

Each MC_*_DB instance DB is created when the block is dropped onto a network. The TO generates these names automatically. Avoid writing to the <TO>.ControlBits or the underlying STW1/NSOLL_A tags directly - the TO owns those bits and writes to its <TO>.StatusBits flags (PowerOn, Error, ErrorStop, AxisHomed, etc.).

9. Alternative: DriveLib Function Blocks

If you need direct access to STW1/ZSW1 or want to read/write drive parameters acyclically without going through a TO, Siemens provides DriveLib - a free block library that mirrors the SINAMICS parameter model. DriveLib is shipped as a TIA Portal library (.zal13 for V13) and contains blocks such as:

• SINA_SPEED - simple open-loop speed control using telegram 1 (writes STW1/NSOLL_A, reads ZSW1/NIST_A).
• SINA_POS - positioner using telegram 111.
• RDREC / WRREC - generic acyclic record read/write (PROFINET record channel to read/write any drive parameter).

DriveLib is documented in detail in the Siemens KB article 109475044. A worked example that combines S7-1200 and G120 with full project download is available in application example 70155469.

Use DriveLib when you need to:

• Access the drive without a technology object (e.g. legacy CPU without motion control, or a fast retrofit).
• Read/write individual drive parameters (e.g. ramp time p1120) at runtime without a TO.
• Implement position control with telegram 111 directly.

Use the Motion Control TO when you want S7-1200-managed motion (jerk limiting, homing, absolute position, multiple coordinated axes). The two approaches are not mutually exclusive but should not run in parallel on the same telegram - they will fight each other on STW1 bit 0.

10. Commissioning and Verification

1. Open Online & Diagnostics on the S7-1200. Confirm the PROFINET device "g120drive" shows Run = green and No fault.
2. Open the TIA Portal Commissioning panel for the G120 (Startdrive > Commissioning). Verify that p0010 = 0 (ready), no active faults in r0947, and r0021 (current speed) = 0.
3. Set the TO online and force "tagEnable". Watch the TO status bits: PowerOn should go TRUE; Error stays FALSE.
4. Force "tagFwd" and verify the drive spins up to 1500 rpm, then check r0021 ≈ 1500. The PROFINET trace tool (Startdrive > Trace) lets you capture STW1/ZSW1/NSOLL_A/NIST_A on a time axis to confirm telegram timing.
5. Force "tagRev". Verify the drive spins in the opposite direction at -1500 rpm.
6. Force "tagStop". Verify the drive decelerates on the configured ramp to 0 rpm.
7. Force a drive fault (e.g. set a low current limit and overload) and confirm MC_Reset clears it after the next Execute edge.

11. Troubleshooting Matrix

12. Field-Proven Notes

• Always wire a hardware enable (terminal 5 on CU240E-2) in addition to the PROFINET STW1 enable. Many safety circuits require a fallback hardwired enable that is independent of the bus.
• Set p864 = 0 if you do not want the drive to start automatically on power-up. Default behavior depends on parameter set.
• For multi-axis machines, give each drive a unique PROFINET name and a unique IP in the same subnet. The device name is required for PROFINET to resolve the device (LLDP), the IP is for TCP services like web server or PROFINET DCP.
• The S7-1200 Motion Control library in TIA V13 supports up to 4 TOs per CPU (F-CPU variants up to 4 motion TOs; non-safety CPUs also limited). For more axes, move to S7-1500.
• If you migrate from PROFIBUS (CU240E-2 non-PN) to PROFINET, the existing PROFIdrive telegram structure and most parameters (p0840, p1155, p2051) carry over - the difference is the physical medium and the device name/IP, not the drive logic.
• Use BOP-2 menu item "Setup -> Commissioning -> Factory reset" only when an upload from a corrupted TIA project is no longer possible; it will erase all drive parameters including motor data.