SEW EURODRIVE DFP21B bus interface

SEW DFP21B PROFIBUS DP-V1 Fieldbus Interface: Complete Guide to Installation, Configuration, and Communication

In modern industrial automation systems, fieldbus technology is the core for achieving efficient data exchange between controllers and drive devices. PROFIBUS DP, as one of the most widely used fieldbuses globally, holds an important position in manufacturing and process industries due to its high speed, determinacy, and openness. The DFP21B tab of SEW-EURODRIVE is MOVIDRIVE ®  MDX61B frequency converter MOVITRAC ®  The B frequency converter and UOH11B gateway housing provide PROFIBUS DP-V1 interface, supporting efficient transmission of cyclic process data and non cyclic parameter data. This article is based on the official manual and systematically explains the installation steps, hardware configuration, project planning, GSD file usage, and 8-byte MOVILINK of DFP21B ®  Provide a complete technical operation guide for automation engineers, including parameter channels, DP-V1 functions, communication examples, and fault diagnosis.

Product Overview and Functional Features

1.1 Application scenarios of DFP21B tab

DFP21B is SEW designed specifically for MOVIDRIVE ®  MDX61B (expandable option version) and MOVITRAC ®  The PROFIBUS DP-V1 fieldbus interface designed for B-series frequency converters. It enables the frequency converter to seamlessly integrate into the PROFIBUS network, achieving:

Real time control (speed, torque, start stop, etc.) through cyclic process data (up to 10 words)

Through a non cyclic parameter channel (8-byte MOVILINK) ®  Or PROFIdrive dataset 47) Read and write all driver parameters

Supports parallel communication between C1 main station (PLC) and C2 main station (diagnostic/visualization equipment) of DP-V1

Through MOVITOOLS ®  MotionStudio conducts remote debugging and diagnosis via PROFIBUS

1.2 Core Features

Unit Profile: Whether using PROFIBUS, DeviceNet, or other buses, the control interface is the same, making it easy to change bus types.

Coexistence of cyclic and non cyclic data: Process data (PD) is periodically exchanged, and parameter data is transmitted non periodically through READ/WRITE services, without affecting the bus cyclic load.

Hardware address setting: The station address is set through DIP switches (1-125), without software configuration, and can be used immediately upon power on.

Monitoring function: Supports fieldbus timeout response, can be configured as quick stop, emergency stop, or maintain the last set value.

Diagnostic function: Integrated fieldbus monitor, compatible with MOVITOOLS ®  View process data and status information.

1.3 Supported Devices

Equipment Description

MOVIDRIVE ®  MDX61B needs to be plugged into a fieldbus slot and supports DFP21B as a DP-V1 slave station

MOVITRAC ®  B uses DFP21B as a gateway to connect the frequency converter on SBus

UOH11B gateway shell independent shell, built-in DFP21B, used to connect multiple SBus devices to PROFIBUS

Installation and wiring

2.1 In MOVIDRIVE ®  Install DFP21B in MDX61B

Important limitations:

MOVIDRIVE size 0 ®  MDX61B can only be installed or removed by SEW engineers with option cards.

Users with sizes 1-6 can operate it themselves.

Installation steps (refer to Figure 2 in the manual):

Disconnect the power supply of the frequency converter and the DC 24V power supply.

Take ESD protection measures (such as anti-static wristbands).

Remove the keyboard and front cover.

Loosen the two screws securing the card holder and pull out the holder evenly.

Remove the two screws from the black cover plate and remove the cover plate.

Place the DFP21B tab on the bracket so that the three positioning screws correspond to the bracket holes.

Push the bracket with the card into the slot, apply slight pressure to engage the connector, and tighten the two fixing screws.

Reinstall the front cover and keyboard.

2.2 In MOVITRAC ®  Install DFP21B (gateway mode) in B

MOVITRAC ®  The installation of option cards for B is also limited to SEW engineers only. DFP21B must be installed at the beginning or end of the SBus connection and have a built-in SBus terminal resistor (S1=ON). Its SBus address is fixed at 0.

SBus wiring (Figure 3):

Use twisted pair shielded copper cable (0.75 mm ²/AWG18120 Ω @ 1 MHz, capacitance ≤ 40 pF/m).

Connect X26 terminals: SC11 (SBus+), SC12 (SBus -), GND.

DC 24V power can be provided to DFP21B through X26.7 (if MOVITRAC ®  X12.8/9 has been powered.

Terminal resistance: The SBus end needs to be connected with S1=ON, and the intermediate station S1=OFF.

Baud rate and bus length:

250 kbaud → 160 m

500 kbaud → 80 m

1000 kbaud → 40 m

2.3 UOH11B Gateway Shell

UOH11B is a standalone gateway enclosure that includes the DFP21B tab. It is connected to SBus through X26 terminals (SC11, SC12, GND, DC 24V) and to PROFIBUS through a 9-pin Sub-D plug. This casing is suitable for handling multiple MOVITRAC ®  B or other SBus devices are centrally connected to the PROFIBUS network.

2.4 PROFIBUS Connection and Pin Allocation

The PROFIBUS interface of DFP21B adopts a 9-pin Sub-D socket (compliant with IEC 61158), with pin definitions:

Pin 3: RxD/TxD-P (positive data)

Pin 8: RxD/TxD-N (data negative)

Pin 5: DGND (reference ground)

Pin 4: CNTR-P (TTL control signal for repeater)

Cable requirements: Use shielded twisted pair cables (type A), with large areas of grounding at both ends of the shielding layer. When the bus length is long or the ground potential fluctuates, it is necessary to make equipotential connections.

Bus terminal: DFP21B itself does not have a terminal resistor. When it is located at the beginning or end of the PROFIBUS segment, a PROFIBUS connector with an integrated terminal resistor must be used and a resistance switch must be turned on.

2.5 Station Address Setting

Station address through DIP switch

two0

two0

to two six

two six

Set within the range of 1 to 125. The default address is 4（two two=four two two=4) . After the address change, it needs to be powered off and restarted to take effect. The current address can be read through parameter P093 (fieldbus address).

Example: Set address 17 → Switch position:

two 0

=one two 0

=1 (1)twofour

=one two four=1 (16), the rest are 0.

2.6 LED Status Indicator Light

Meaning of LED color status

RUN green constant light bus hardware is normal

RUN green flashing 2 Hz address>125 or=0

RUN green off hardware malfunction

BUS FAULT is constantly red and disconnected from the DP master station, with no detected baud rate

BUS FAULT flashing red detected baud rate but not addressed by the master station (configuration error)

BUS FAULT red off, data exchange is normal

H1 (gateway) red constant light system error (not configured or offline driver)

H1 (gateway) flashing red bus scanning in progress

H1 (gateway) red off, SBus normal

Project Planning and GSD Documents

3.1 GSD file selection

Usage scenario GSD file identifier description

MOVIDRIVE ®  MDX61B (standard DP) SEW_6003.GSD MOVIDRIVE ®+ DFP21 DP-V0， No DP-V1 parameter channel

MOVIDRIVE ®  MDX61B（DP-V1） SEWA6003.GSD MOVIDRIVE ®- DFP21B supports DP-V1 parameter service

Gateway mode (MOVITRAC) ®/ UOH11B) SEW_6009.GSD DFP21B Gateway for SBus Multi Slave Gateway

Attention: GSD files cannot be modified, otherwise SEW will not be held responsible. The latest version can be downloaded from the SEW official website.

3.2 Project Planning Steps (Taking STEP7 as an Example)

Copy the GSD file to STEP7 .. S7DATA GSD directory.

Add DFP21B slave station in hardware configuration and set PROFIBUS address.

Select the required process data configuration (see table below).

Allocate I/O addresses (note: when the data length is ≥ 3 bytes, SFC14/15 must be used to ensure consistency).

Compiling and downloading, if the BUS FAULT LED turns off, it indicates successful configuration.

3.3 MOVIDRIVE ®  DP configuration options

Process Data Configuration DP Configuration Code Description

1 PD F0 hex 1 process data word (control word/status word)

2 PD F1 hex 2 words (+speed)

3 PD F2 hex 3 words (+slope)

6 PD 00 hex, F5 hex 6 words (PD4~PD6 only used for IPOSplus) ®）

10 PD 00 hex, F9 hex 10 words

Param+1 PD F3 hex, F0 hex 8-byte parameter channel+1 PD word

Param+2 PD F3 hex, F1 hex parameter channel+2 PD

Param+3 PD F3 hex, F2 hex parameter channel+3 PD

Param+6 PD F3 hex, F5 hex parameter channel+6 PD

Param+10 PD F3 hex, F9 hex parameter channel+10 PD

General module configuration: If you need to customize the number of PDs (4, 5, 7, 8, 9), you can choose "Universal Module", but you must ensure that the input/output word count is equal, and module 0 is fixed to 0x00. Module 1 is the parameter channel (0x00 means disabled, 0x00 0x87 0x87 means enabled 8 bytes), and subsequent modules are PD data.

3.4 Configuration of Gateway Mode (SEW_6009. GSD)

In gateway mode, the DP master station communicates with DFP21B, which then exchanges data with up to 8 frequency converters through SBus. Each frequency converter occupies 3 process data words (PO1~PO3, PI1~PI3). The configuration options include:

ONE module for all drivers: All drivers' PDs are concentrated in a consistent data block (length=3 x n words).

ONE module per drive: Each driver has a separate consistent data block (for ease of programming).

The process data configuration table can be found on page 37 of the manual, supporting 1-8 drivers (3-24 PD).

3.5 AutoSetup (Gateway Automatic Setup)

After activating the AutoSetup DIP switch, DFP21B automatically scans the frequency converters (addresses 1-8) on the SBus and assigns 3 PD words to each detected device. This function only needs to be executed once (the switch remains ON). If you want to change the allocation of equipment or process data on SBus, you need to switch AutoSetup again.

Variable frequency drive parameter settings

4.1 MOVIDRIVE ®  MDX61B

P100 (Setpoint Source)=FILDBUS

P101 (control signal source)=FILDBUS

P819 (fieldbus timeout): configured by the DP master station and cannot be changed through the keyboard.

P831 (fieldbus timeout response): Optional options include "quick stop/warning", "emergency stop/fault", etc.

Note: Even if fieldbus control is used, for safety reasons, the frequency converter still needs to be enabled through terminals (DI00 "/Controller inhibit" connected to+24V, DI01~DI03 can be set to "no function").

4.2 MOVITRAC ®  B (Gateway Mode)

P100=SBus (Setpoint Source)

P101=SBus (control signal source)

P813 (SBus address): Set to 1-8 (cannot use 0 due to gateway occupancy)

P815 (SBus timeout): Recommended 50-200 ms

Terminal Enable: DI1 (CW/stop) is connected to+24V, and the remaining terminals are set to "No Function"

Loop process data and parameter channel

5.1 Process Data Exchange

The DP master station sends control words, speed settings, ramp time, etc. through process output data (PO); The frequency converter returns status words, actual speed, current, etc. through process input data (PI). In SIMATIC S7:

1-2 PD words can be directly accessed using the L/T instruction.

≥ 3 PD words must use SFC14 (DPRD_DAT) and SFC15 (DPWR_daT) to ensure data consistency.

5.2 8-byte MOVILINK ®  Parameter channel structure

The parameter channel is located before the process data (when "Param+x PD" is configured), and its structure is as follows:

Byte name description

0 Management service identifier, data length, handshake bit, status bit

1 Subindex reserved, must be 0x00

2 Index high parameter index high byte

3 Index low parameter index low byte

4-7 Data 4-byte data (MSB in byte 4, LSB in byte 7)

Definition of Byte 0 bits for management:

Position 0~3: Service identifier (0001=READ, 0010=WRITE)

Bit 4-5: Data length (11=4 bytes, must be set to 3)

Position 6: Handshake position (needs to be flipped every time a new task is created)

Bit 7: Status bit (0=Success, 1=Error)

5.3 READ Service Execution Steps

Set index (byte2-3).

Set the management byte to 0x01 or 0x41 (for READ service only, regardless of data length).

Changing the handshake position (such as from 0 to 1) triggers the service.

Wait for the handshake position returned by the frequency converter to match the sent value.

Read data values from bytes 4-7.

If the status bit is 1, then byte4-7 is the return code (error class, error code, additional code).

5.4 WRITE Service Execution Steps

Set the index and data values (byte4-7).

Set management byte: Service identifier 0010 (WRITE), data length 11 (4 bytes), handshake bit flip, status bit=0 → typical value 0x32 or 0x72.

Trigger service (handshake position change).

Waiting for confirmation. If the status bit is 0, the write is successful; If=1, return an error code.

Data format: All parameter values are 4 bytes, aligned to the right (LSB in byte 7). For detailed data scope, please refer to "MOVIDRIVE ®  Parameter List ".

5.5 Return Code (Error Diagnosis)

When WRITE or READ fails, byte4-7 returns the following information:

Byte content

4 Error classes

5 Error codes

6-7 Additional code

Common Additional Codes (SEW Specific):

0x0810: Illegal parameter index

0x0811: Function/parameter not implemented

0x0812: Read only

0x0813: Parameter lock activated

0x0815: Parameter value too large

0x0816: Parameter value too small

0x0817: Required option card not installed

0x081C: Controller Inhibit Required

0x081D: Invalid parameter value

Special error:

Service identifier encoding error → Error class 0x05, error code 0x05

The data length is not 4 bytes → Error class 0x06, error code 0x08

Internal communication error → Error class 0x06, error code 0x02 (recommended to power off and restart)

Detailed explanation of PROFIBUS DP-V1 function

6.1 Basic Concepts of DP-V1

PROFIBUS DP-V1 adds a non cyclic READ/WRITE service on the basis of standard DP, allowing the transmission of large amounts of parameter data without affecting the cyclic process data cycle. Main roles:

C1 main station (such as PLC): responsible for cyclic data exchange, and can also initiate non cyclic parameter requests.

C2 main station (such as PC, HMI): only performs non cyclic communication and supports multiple parallel connections.

6.2 Dataset 47 (DS47)

The SEW drive device uses dataset 47 as the DP-V1 parameter channel. Its structure supports two access modes:

MOVILINK ®  Service (Request ID=0x40): capable of executing read, write, write volatile (write only to RAM), etc.

PROFIdrive service (Request ID=0x01 Request parameter, 0x02 Change parameter): Compliant with PROFIdrive specification V3.1.

Key elements of dataset 47:

Request reference: Used to match requests and responses.

Request ID/Response ID: Identify the service type and positive or negative response.

Axis: Used for addressing in multi axis systems (MOVIDRIVE) ®  Fixed at 0).

No. of parameters: usually 1.

Attribute: For MOVILINK ®， The upper half byte is the service identifier (0x1=Read, 0x2=Write, 0x3=Write volatile).

Parameter number: OVILINK parameter index.

Subindex: Always 0.

Format: 0x43 (two characters), 0x44 (error).

No. of values: usually 1.

Value/Error value: Data or error code.

6.3 DP-V1 Communication Timing

The master station sends a Write. req (DS47) to write the parameter request to the slave station.

Processing requests from the slave station (which may take several milliseconds).

The main station sends READ.req query responses periodically.

If the slave station returns error code 0xB5 (status conflict), it indicates that it has not been processed yet, and the master station needs to repeat READ until a positive response is received.

When responding positively, READ.res contains parameter values or write confirmations.

6.4 MOVILINK ®  Read Example (Read firmware version, index 8300)

WRITE.req user data:

Request reference = 0x01

Request ID = 0x40

Axis = 0x00

No. of parameters = 0x01

Attribute = 0x10（READ）

No. of elements = 0x00

Parameter number = 0x206C（8300 dec）

Subindex = 0x0000

Positive response READ.res:

Response ID = 0x40

Format = 0x43

No. of values = 0x01

Value=0x311C7289 (823947913 → firmware version 823 947 9.13)

6.5 MOVILINK ®  Write example (volatile write IPOS variable H0, index 11000, value 12345)

WRITE.req：

Attribute = 0x30（WRITE volatile）

Parameter number = 0x2AF8

Value = 0x00003039（12345 dec）

6.6 PROFIdrive Write Example (non-volatile write fixed set point n11, index 8489)

WRITE.req：

Request ID = 0x02

Attribute = 0x10

Parameter number = 0x2129

Value = 123（0x7B）

Attention: The Change parameter of PROFIdrive will be written to EEPROM, and frequent operation may reduce its lifespan. For high-frequency parameter modification, MOVILINK should be used ®  WRITE volatile。

6.7 DP-V1 Error Code (Telegram Layer)

The meaning of Error Class Error Code

0xB (access) 0x0 Invalid index (e.g. DS47 does not exist)

0xB 0x5 status conflict (0xB5), please retry READ

0xB 0x7 invalid range (DS47 header error)

0xC (resource) 0x2 Resource busy

Running MOVITOOLS via PROFIBUS ®  MotionStudio

7.1 Hardware and software requirements

Hardware: Siemens CP5512 (PCMCIA) or CP5611 (PCI) PROFIBUS master card.

software

STEP7 V5.3 SP3 or higher (optional)

SIMATIC NET Softnet DP Driver (V6.0+)

MOVITOOLS ®  MotionStudio V5.20+

7.2 Configuration steps

Install drivers and software.

Select the CP card in "Set PG/PC Interface" and set the parameters (baud rate, station address, uncheck "Unique Master Station").

Diagnostic test: Click "Test" to confirm OK, and click "Read" to list all devices on the bus.

Start MOVITOOLS ®  MotionStudio， Open the SEW communication server.

Add PROFIBUS communication channel by drag and drop, configure as C2 master station.

Perform unit scan (F5), locate online devices, switch to online mode to perform parameter reading and writing, oscilloscope monitoring, etc.

7.3 Common Problems

The bus terminal resistance is not set correctly.

The PC address conflicts with an existing master station.

Checking 'PG/PC is the only master on the bus' prevents coexistence with C1 master station.

The baud rate does not match the actual bus rate.

Fault diagnosis

8.1 Diagnostic Process

Problem 1: The frequency converter is not working on PROFIBUS (BUS FAULT is on)

Check cable connections and terminal resistance.

Is the checkpoint address within the range of 1-125.

Check if the GSD file is correct and if the configuration has been downloaded.

Check if the main station is running.

Problem 2: The frequency converter can communicate but cannot be controlled

Check if P100/P101 is set to FILDBUS (or SBus).

Use P094~P097 to check if the process data is received correctly.

Check if the terminal enable signal has been provided.

Check if SFC14/15 is used in the program to ensure data consistency.

8.2 Fault code list (optional)

Possible causes and countermeasures for fault code names

28 fieldbus timeout, master-slave communication interruption check, master station communication, extend monitoring time

37 Watchdog Error System Software Error Contact SEW Service

45 initialization error reset after self check failure, power off and restart. If it repeatedly occurs, send it for repair

111 system error (gateway): The device on SBus cannot be addressed or the DFP itself is faulty. Check the SBus wiring and terminal resistance, and power on again

Technical Data Summary

9.1 DFP21B for MOVIDRIVE ®  MDX61B

Parameter values

Order number 824 240 2

Power consumption 3 W

Baud rate 9.6 k~12 Mbaud automatic detection

Connector 9-pin Sub-D, compliant with IEC 61158

Station address 1-125 (DIP switch)

GSD file SEW_6003.GSD/SEWA6003.GSD

DP identification number 6003 hex (24579 dec)

Maximum PD quantity of 10 words

Diagnostic data 8 bytes

9.2 DFP21B is used for gateway mode (MOVITRAC) ®  B / UOH11B）

Parameter values

External power supply DC 24V (-15%/+20%), Imax ≤ 200 mA, Pmax=3.4 W

Baud rate is the same as DP

GSD file SEW_6009.GSD

DP identification number 6009 hex (24585 dec)

The maximum number of SBus slave stations is 8

Each slave station has a PD number of 3 characters (fixed)

9.3 Environment and Dimensions

Working temperature: 0 ° C~+55 ° C

Storage temperature: -25 ° C~+70 ° C

Protection level: IP20

UOH11B shell dimensions (width x height x depth): approximately 83 x 75 x 22.5 mm (can be installed on DIN rails)