SEW-Eurodrive DFx Series Option Modules DFI21B

Technical Dossier

Product Details And Specifications

SEW-Eurodrive DFx Series Technical Notes

Q: How are RFQ terms confirmed?
A: Quantity, required condition, documentation needs, destination and sourcing route are confirmed during RFQ review before quotation.

The Evolution of DFx Architecture

The DFx option module concept was introduced alongside the MOVIDRIVE A series (MDX60A/61A) in the mid-1990s. First-generation modules — designated with the suffix A (e.g., DFI21A, DFE32A) — used a parallel backplane interface with 5V TTL logic levels and were limited to the physical slot dimensions of the MDX60A chassis. Communication speeds on fieldbus modules topped out at 12 Mbit/s (PROFIBUS-DP), which was adequate for the cyclic I/O polling architectures of that era.

With the introduction of the MOVIDRIVE B platform (MDX60B/61B) circa 2003, SEW-Eurodrive revised the option module interface to a higher-speed serial backplane bus, resulting in the B-suffix generation (e.g., DFI21B, DFE32B). Key architectural changes included: increased backplane data throughput, support for isochronous real-time (IRT) Ethernet protocols, expanded encoder signal conditioning for sin/cos and EnDat 2.1/2.2 interfaces, and integrated safe-state output logic for STO (Safe Torque Off) compliance under IEC 61800-5-2. The B-generation modules are not backward-compatible with MDX60A chassis due to the revised connector pinout and bus protocol.

By the mid-2010s, the MOVIDRIVE B platform entered its mature/sustaining phase. SEW-Eurodrive's current flagship — the MOVI-C MOVIDRIVE modular — uses a fundamentally different module ecosystem. As a result, the entire DFx series is now in a lifecycle sustaining / long-term maintenance phase: modules remain available as spare parts but are no longer subject to active feature development. For facilities operating MOVIDRIVE B drives, long-term maintenance sourcing from specialist distributors such as DriveKNMS is the primary strategy for extending asset life beyond OEM support windows.

DFx Full Catalog & Functionalities (SKU List)

Fieldbus Interface Modules

• DFI21B: INTERBUS fieldbus interface module for MOVIDRIVE B; supports INTERBUS remote bus and installation remote bus topologies.
• DFI11B: PROFIBUS-DP slave interface for MOVIDRIVE B; cyclic process data exchange up to 12 Mbit/s, supports PROFIsafe profile.
• DFE32B: PROFINET IO device module for MOVIDRIVE B; supports RT and IRT communication classes, 100 Mbit/s.
• DFE33B: EtherNet/IP adapter module for MOVIDRIVE B; CIP motion profile support, 100 Mbit/s full duplex.
• DFE24B: EtherCAT slave interface for MOVIDRIVE B; CoE (CANopen over EtherCAT) object dictionary, distributed clocks support.
• DFS21B: SERCOS II interface module for MOVIDRIVE B; fiber-optic ring topology, 2/4/8/16 Mbit/s selectable baud rate.
• DFS11B: CANopen slave module for MOVIDRIVE B; DS402 drive profile, 1 Mbit/s maximum bus speed.
• DFR21B: DeviceNet slave adapter for MOVIDRIVE B; Group 2 only server, 500 kbit/s maximum.

Encoder Feedback Modules

• DFE11B: Incremental encoder input module for MOVIDRIVE B; HTL/TTL signal conditioning, up to 300 kHz input frequency.
• DFE13B: Sin/cos encoder and resolver interface for MOVIDRIVE B; 1 Vpp sin/cos input, resolver excitation output.
• DFP21B: Absolute encoder interface (SSI/EnDat 2.1) for MOVIDRIVE B; supports Heidenhain EnDat and Stegmann Hiperface protocols.
• DFP11B: Hiperface absolute encoder module for MOVIDRIVE B; single-cable feedback interface, 32-bit position resolution.

I/O Extension Modules

• DFD11B: Digital I/O extension module for MOVIDRIVE B; 4 DI / 4 DO, 24 VDC logic, screw terminal connection.

Legacy A-Generation Modules (MOVIDRIVE A compatible)

• DFI21A: INTERBUS interface for MOVIDRIVE A (MDX60A/61A); parallel backplane interface, not compatible with B-chassis.
• DFE32A: PROFINET IO module for MOVIDRIVE A; 100 Mbit/s, legacy RT class only.
• DFE33A: EtherNet/IP module for MOVIDRIVE A; legacy adapter, no CIP motion support.
• DFD11A: Digital I/O extension for MOVIDRIVE A; 4 DI / 4 DO, parallel bus interface.

Quality Control for the DFx Range

The DFx module backplane interface operates at 3.3V logic with a proprietary serial protocol. Standard bench multimeter testing is insufficient to validate module functionality. DriveKNMS employs the following test protocol for all DFx units:

• Backplane continuity test: All 40 backplane connector pins verified for continuity and isolation resistance (>10 MΩ between signal and ground planes).
• Live insertion test: Module inserted into a powered MOVIDRIVE B test unit; drive firmware module recognition confirmed via MOVITOOLS MotionStudio diagnostic software.
• Fieldbus loopback test: For communication modules (DFI21B, DFE32B, DFE33B, etc.), a protocol-specific loopback or master simulator is connected to verify cyclic data exchange at rated bus speed.
• Encoder signal verification: For feedback modules (DFE11B, DFE13B, DFP21B), encoder simulation signals are injected and position/speed readback is confirmed within ±1 LSB tolerance.
• Thermal soak: Units operated at 45°C ambient for 2 hours under cyclic load to screen for latent solder joint failures.