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ST/SN AC Synchronmotoren

ST/SN Series AC Synchronous Motors

ST and SN Series synchronous motors provide high performance in three frame sizes, NEMA 23, 34 and 42 (60, 90 and 110 mm). Resistor-capacitor kits are also available. These motors are driven economically from standard AC line voltage and the synchronous speed is related to the line frequency.

Limited availability outside North America


  • ST models: NEMA 23 (60 mm), three stack length options with torque ratings to 131 N-cm (185 oz-in)
  • SN3 models: NEMA 34 (90 mm), three stack lengths with torque ratings from 198 to 636 N-cm (280 to 900 oz-in)
  • SN4 models: NEMA 42 (110 mm), three stack lengths with torque ratings from 500 to 1059 N-cm (715 to 1500 oz-in)
  • All models offer flying lead, terminal box, connector and shaft extension options
  • 72 rpm motor speed (with 60 Hz voltage)
  • Constant speed does not vary with load
  • 120 volt AC models
  • Fast starting, stopping and reversing
  • Can be stalled indefinitely without overheating
  • Standard connections include leaded, terminal box, MS connectors, rear shaft


Model NEMA Frame Sizes Rated Torque (oz-in) Max Load Inertia (oz-in-s1) Standard Options
ST Series 23 4 80-185 0.02 - 0.15 L, T, MS, RS
SN3 Series 34 4 280-900 0.19 - 0.46 L, T, MS, RS
SN4 Series 42 3 715-1,500 0.32 - 0.69 L, T, MS, RS

Media & Downloads

Title Language Date Share URL
Kollmorgen Catalogo Automazione e Motion Control IT Italian Share URLview
Kollmorgen Full-line Catalog English Share URLview
Kollmorgen otomasyon ve hareket kontrol çözümleri kataloğu TR Turkish Share URLview
Stepper and Synchronous Motors Catalog EN Rev C English Share URLview
科尔摩根运动控制及伺服系统解决方案 Chinese, Simplified Share URLview

These 3D models are intended to guide your design activities and may be used as reference information. Be sure to consult a Kollmorgen expert to ensure you have the most current and accurate information for critical aspects of design work.

Title File Language Date Share URL
Superior Stepper Connection Diagrams EN.pdf English
Share URL /sites/default/files/public_downloads/Superior-Stepper-Connection-Diagrams_en-US.pdf
Superior Synchronous Connection Diagrams en US.pdf English
Share URL /sites/default/files/public_downloads/Superior-Synchronous-Connection-Diagrams_en_US.pdf
Title File Language Date Share URL
Blue Guide English, German
Share URL
Kollmorgen EU Declaration of Conformity PowerPac K-N-SN English
Share URL /sites/default/files/public_downloads/Kollmorgen%20EU%20Declaration%20of%20Conformity%20PowerPac%20K-N-SN.pdf

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