SEW-Eurodrive SA57 DRN71M4 Gearmotor 0.37kW 17 RPM 230/400V

SEW-Eurodrive SA57 DRN71M4 Helical-Worm Gearmotor (0.37 kW | 1415/17 RPM | 220–240 / 380–415 V)

The SEW-Eurodrive SA57 DRN71M4 is right-angle helical-worm gearmotor designed for high-shock, high-torque industrial and marine auxiliary operations. Engineered to combine an energy-efficient DRN-series 4-pole asynchronous AC motor with an SA-series helical-worm reduction gearbox, this drive yields high mechanical damping and smooth torque transfer.

The helical-worm arrangement utilizes a case-hardened steel worm mesh paired with a high-tin bronze worm wheel. The “SA” configuration specifies a hollow shaft with keyway, eliminating the need for external flexible couplings, minimizing drive train runout, and enabling direct mounting onto driven equipment shafts. The motor winding is rated for multi-voltage wide-range service (220–240 V Delta / 380–415 V Star at 50 Hz), making it directly deployable on European grid standards, vessel marine switchboards, and international variable frequency drive (VFD) bus architectures.

Motor Features

• IE3 Premium Efficiency DRN Motor: Fitted with SEW’s high-efficiency DRN71M4 motor architecture, lowering internal copper/iron losses, operating temperatures, and operational power consumption.
• Direct Torque Hollow-Shaft Transmission: DIN-compliant keyed hollow bore slips directly onto client driving shafts to eliminate alignment errors, chain/belt guards, and premature coupling wear.
• High-Efficiency Helical-Worm Reducer: Combines an optimized helical pre-stage with high-reduction worm gearing for quiet operation and higher operational efficiency than conventional pure-worm gearboxes.
• Robust Mechanical Damping: Helical-worm geometry inherently absorbs and dissipates torsional shudder, start-stop shock loads, and equipment jams common in reciprocating feeder and vessel hoist systems.

Compatible Drive Units & Replacements

• SEW Direct Legacy Matches: Direct interchangeability with previous-generation SA57 DT71D4, SA57 DRE71M4, and S57 DRN71M4 (solid shaft version).
• Modular Gearbox Interchanges: Flange patterns and primary reduction interfaces directly swap with SEW SAF57 (B5 Flange-mount), SH57 (Hollow shaft with shrink disk), and SAZ57 (B14 Short-flange) variants.
• Inverter Platform Compatibility: Fully verified with SEW MOVIDRIVE, MOVITRAC, Siemens SINAMICS G120, Danfoss VLT AutomationDrive, and ABB ACS580 drive families.

Manufacturer Part Numbers (MPN) & Codes

• Base Model Configuration: SA57 DRN71M4
• Common OEM Order Designations: SA57/T DRN71M4/TH, SA57 DRN71M4/BE05 (with spring-loaded brake), SA57DRN71M4-0.37KW-17RPM
• Housing Casting Stamp Identifiers: Series 57 S-Housing (GG20 Grey Cast Iron).

Frequently Asked Questions

What does the “SA” designation signify compared to standard “S” or “SF” models?

In the SEW-Eurodrive nomenclature, “SA” denotes a right-angle helical-worm drive equipped with a hollow shaft and standard keyway. The plain “S” indicates a solid output shaft with foot mounting, while “SF” indicates a solid output shaft fitted with a B5 mounting flange.

Can this motor operate on 60 Hz networks?

Yes. When connected to a 60 Hz 3-phase supply (typically 440–480V in Star configuration), the synchronous speed increases by 20%. The input speed rises from 1415 RPM to approximately 1700–1730 RPM, and output speed scales proportionally from 17 RPM to roughly 20–21 RPM. Check driven equipment limits and service factors before continuous 60 Hz deployment.

How do I configure the motor for variable speed inverter (VFD) operation?

The DRN71M4 motor can be controlled by any standard pulse-width modulated (PWM) inverter. For constant torque applications running below 20 Hz, monitor internal motor temperatures or fit a separately powered forced cooling fan (SEW /V option), as the internal shaft-mounted fan loses cooling throughput at low RPMs.

What lubricant is recommended for the SA57 gearbox?

SEW recommends synthetic polyalphaolefin (PAO) or polyglycol (PG) gear oils with an ISO VG 460 viscosity grade for helical-worm units under standard ambient conditions (-20°C to +40°C). Synthetic oils dramatically reduce friction on the bronze worm wheel, boosting mechanical efficiency and extending drain intervals up to 15,000–20,000 operating hours.

Does the gear unit provide a complete self-locking function?

At a ratio of 83.24:1, the SA57 helical-worm gear unit exhibits high static friction and partial self-retardation, but it cannot be classified as fully self-locking under dynamic shock, vibration, or back-driving loads. For load-holding hoisting or inclined conveyor safety requirements, an integrated mechanical motor brake (such as the SEW BE05 fail-safe brake) is strictly required.