SEW-Eurodrive DFS Series

Questions and Answers

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Robert SmithAug 14, 2025
Why does my SEW-Eurodrive DFS Engine motor overheat?
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  Shelby CraigAug 14, 2025
  Your SEW-Eurodrive Engine motor may overheat due to several reasons: * Overload: Check the load with the controller current and configuration data. * Inadequate cooling: Adjust the cooling air supply or clear any blockages. Consider fitting a forced cooling fan. * Forced cooling fan not operating: Check the fan's connection and correct it if necessary. * Ambient temperature too high: Reduce the power. * Selected duty exceeded: Match the motor duty to the required operating conditions. Expert advice is recommended for selecting the correct drive. * Servo controller not optimized: Check the servo controller.
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Peter HoganAug 17, 2025
What to do if my SEW-Eurodrive DFS motor will not start?
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  Christopher AdamsAug 17, 2025
  If your SEW-Eurodrive Engine motor won't start, here are a few things to check: * **Lead broken**: Check and restore the connections. * **Fuse blown**: Check the servo controller and replace the fuse. * **Circuit-breaker tripped**: Check the circuit-breaker, adjust if necessary, and check the drive for possible overload. * **Servo controller defective, connected incorrectly, or set incorrectly**: Check the servo controller and wiring.
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christopher71Aug 20, 2025
Why is my SEW-Eurodrive DFS Engine brake not releasing?
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  Michael BondAug 21, 2025
  The brake on your SEW-Eurodrive Engine might not be releasing due to the following reasons: * Wrong voltage at the brake: Apply the correct voltage (see nameplate). * Brake control unit failed: Replace the brake control unit, check the brake coil, the switching devices, and the connection. * Brake connected incorrectly: Check the brake connection. * Max. permissible working air gap exceeded due to worn brake lining: Replace the whole brake disc. * Voltage drop on the supply lead > 10 %: Ensure the correct supply voltage is connected and check the lead cross-sections. * Brake coil interturn fault or short circuit to frame: Change the complete brake with control unit and check the switching devices.
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Holly ConleyAug 23, 2025
Why is my SEW-Eurodrive DFS motor too noisy?
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  rlambertAug 25, 2025
  Excessive noise from your SEW-Eurodrive Engine motor can be caused by: * Ball bearings distorted or damaged: Re-align the motor, check the driven machine, and replace the ball bearings. * Rotating parts vibrate: Rectify the cause or correct the imbalance. * Forced cooling fan: foreign matter in the cooling air passages: Clean the cooling air passages.
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Stacy FreemanAug 27, 2025
What causes a SEW-Eurodrive DFS brake to operate after a delay?
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  Todd VegaAug 27, 2025
  A delayed brake operation in your SEW-Eurodrive Engine is caused by the brake being switched in the AC circuit. To resolve this, ensure simultaneous switch-off in the DC and AC circuits, referring to the wiring diagram.
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Anna ReynoldsAug 31, 2025
Why is my SEW-Eurodrive Engine brake noisy?
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  Heidi CookAug 31, 2025
  Brake noise in your SEW-Eurodrive Engine can be attributed to: * Worn gearing due to jerky starting: Check drive configuration. * Oscillating torques due to incorrect servo controller setting: Check/correct servo controller setting in accordance with the Installation and Operating Instructions.
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charleswalkerSep 2, 2025
Why is the SEW-Eurodrive Engine rotation direction wrong?
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  Susan ParkSep 3, 2025
  An incorrect rotation direction in your SEW-Eurodrive Engine is caused by incorrect motor control. Check the servo controller and setpoints, and change over setpoint leads.
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sarahwilsonSep 6, 2025
What causes a SEW-Eurodrive DFS brake to not brake?
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  Troy MullinsSep 6, 2025
  If the brake in your SEW-Eurodrive Engine is not braking, it could be due to: * Worn braking lining: Change the whole brake disc. * Manual brake release incorrectly set: Adjust the setting nuts. * Braking torque incorrect: Change the braking torque.
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Kelly CherrySep 9, 2025
Why does my SEW-Eurodrive DFS motor hum?
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  solomonnicholasSep 9, 2025
  A humming sound in your SEW-Eurodrive Engine motor could indicate: * Drive blocking: Check the drive. * Fault on resolver lead: Check the resolver lead. * Brake cannot be released: Check the brake. * Servo controller not set correctly: Check servo controller.

Summary

General Notes

1.1 How to use the operating instructions

Explains how to read and use the manual.

1.2 Structure of the safety notes

Details the structure and meaning of safety notes.

1.3 Rights to claim under limited warranty

Outlines warranty claim prerequisites and process.

1.4 Exclusion of liability

States liability exclusion for non-compliance with instructions.

Safety Notes

2.1 General information

Provides general safety information for motor operation.

2.2 Target group

Identifies qualified personnel for mechanical and electrical work.

2.3 Designated use

Specifies the intended use and prohibited applications.

2.4 Other applicable documentation

Lists other relevant publications and documents.

2.5 Transportation;storage

Provides guidelines for safe transportation and storage.

2.6 Installation;assembly

Refers to mechanical and electrical installation sections.

2.7 Electrical installation

Details requirements for electrical installation.

2.8 Startup;operation

Advises on handling operational changes and startup.

2.9 Inspection;maintenance

Refers to the inspection and maintenance section.

2.10 Disposal

Outlines product components for disposal.

Motor Structure

3.1 DFS synchronous servomotor - general structure

Illustrates and lists components of the DFS servomotor.

3.2 CFM synchronous servomotor - general structure

Illustrates and lists components of the CFM servomotor.

3.3 Nameplate, unit designation and serial number

Explains the meaning of nameplate details and unit designation.

Mechanical Installation

4.1 Required tools;resources

Lists standard tools and equipment needed for installation.

4.2 Before you begin

Specifies prerequisites for drive installation.

4.3 Preliminary work

Details cleaning and preparation steps before installation.

4.4 Installing the motor

Provides instructions and warnings for motor installation.

4.5 Mounting tolerances

Specifies diameter and centering tolerances for mounting.

Electrical Installation

5.1 Assembling the connector

Provides steps for correctly assembling connectors.

5.2 Wiring notes

Offers notes on protection against interference and thermal protection.

5.3 Connecting the motor and encoder system using SM..;SB.. plug connectors

Details connecting motors and encoder systems via plug connectors.

5.4 Dimensioning the cable cross section

Explains how to determine the minimum required cable cross section.

5.5 Power cables for DFS motors

Describes the structure of power and brakemotor cables for DFS motors.

5.6 Power cables for CFM motors

Shows the structure of CFM motor and brakemotor cables.

5.7 Feedback cable for resolver

Describes the structure of resolver feedback cables.

5.8 Feedback cable for HIPERFACE encoders

Describes the structure of HIPERFACE® encoder feedback cables.

5.12 Connecting the motor via the terminal box

Explains how to connect motors using terminal boxes.

5.13 Connecting the BR brake (CFM motor)

Details how to connect the BR brake for CFM motors.

5.14 Connecting the B brake (DFS56 motor)

Explains how to connect the B brake for DFS56 motors.

5.15 Accessory equipment

Covers TF and KTY temperature sensors, and forced cooling fans.

Startup

6.1 Prerequisites for startup

Lists essential checks and conditions before startup.

Malfunctions

7.1 Motor malfunctions

Lists common motor malfunctions and their remedies.

7.2 Malfunctions when operated with a servo inverter

Addresses issues when motors are used with servo inverters.

7.3 Brake malfunctions

Lists common brake malfunctions and their remedies.

Inspection;Maintenance

8.1 Safety notes regarding inspection;maintenance

Outlines safety precautions for inspection and maintenance.

8.2 Inspection intervals

Advises on determining required inspection intervals.

8.3 Inspection work for the B brake (DFS)

States that the DFS56 brake requires no maintenance and cannot be retrofitted.

8.4 Inspection work for the B brake (CFM)

Explains how to measure the brake's working air gap.

8.4.2 Retrofitting the manual brake release CFM71 and CFM90

Details the procedure for retrofitting manual brake release.

8.4.3 Retrofitting the manual brake release CFM112

Details the procedure for retrofitting manual brake release for CFM112.

Technical Data

9.1 Main technical data of the servomotors

Explains the abbreviations used in the technical data tables.

9.1.2 Technical data of DFS;CFM motors

Presents technical data for DFS/CFM motors with 400V and 230V.

9.2 Plug connectors

Lists plug connector types and their specifications.

9.3 Connection with terminal box

Details connection types for terminal boxes.

9.4 Work done, braking torques

Provides data on work done and braking torques.

9.5 Brake coil resistance

Lists brake coil resistance values for different voltages.

9.6 BR brake - operating currents

Details operating currents for BR brakes.

Appendix

10.1 Crimping tools

Lists required tools for cable assembly and disassembly.

10.2 SM11;SB11 power connector assembly (for DFS56 servomotor)

Lists parts supplied for SM11/SB11 power connector assembly.

10.3 Assembly of SM5.;SM6. and SB5.;SB6. power connectors

Details the assembly of SM5/SM6 and SB5/SB6 power connectors.

10.4 Assembly of signal plug connectors (resolver;HIPERFACE)

Lists parts supplied for signal plug connector assembly.

10.5 Wiring diagrams for DFS;CFM synchronous servomotors

Explains symbols and color codes used in wiring diagrams.

10.6 Wiring diagram for CFM motors with power connector

Shows wiring diagrams for CFM motors with power connectors.

10.7 Wiring diagram for CFM motors with signal connector

Provides wiring diagram for RH.M/RH.L resolver with CFM motors.

10.8 Wiring diagram for CFM motors with terminal box

Shows wiring diagrams for CFM motors with terminal box.

10.9 Wiring diagram for DFS motors with power connector

Shows wiring diagrams for DFS motors with power connectors.

10.10 Wiring diagram for DFS motors with signal connector

Provides wiring diagram for RH1M resolver with DFS motors.

10.11 Wiring diagram for DFS motors with terminal box

Shows resolver wiring diagrams for DFS motors with terminal boxes.

10.12 Wiring diagram for VR forced cooling fan

Illustrates VR forced cooling fan connections.

Address List