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Kollmorgen B-204-C-21
Product Brief: 3-phase interior permanent magnet (IPM/NdFeB) synchronous servo motor offering high torque density and low cogging for dynamic point-to-point motion. Frame “20” = 20-size (flange ≈ 89 mm / 3.5 in square — NEMA 34 mounting pattern). “C” = winding code (medium torque/speed for 230 V bus). Supplied with integral resolver or encoder (factory-fitted — verify from nameplate). Compatible with SERVOSTAR S300/S600/S700 and AKD drives.
Detailed content
Frame Size (Designation): B-20x — flange 88.9 mm × 88.9 mm (NEMA 34), pilot dia. ≈ 63.5 mm, 4× M6 mount holes on 101.6 mm BCD
Shaft Diameter: 12.7 mm (0.500 in) with keyway (standard B-series)
Rated / Continuous Stall Torque (Tc): ≈ 1.8 – 2.2 Nm (C-winding typical for B-204 frame)
Peak Torque (Tp, short-term): ≈ 5.4 – 6.6 Nm (3× continuous)
Rated Speed (nN): 3000 rpm (standard C-winding @ 230 VAC line)
Rated Power (Continuous): ≈ 0.55 – 0.7 kW
Rated Current (RMS): ≈ 2.5 – 3.5 A
Peak Current (RMS): ≈ 7.5 – 10.5 A
Torque Constant (Kt, line-line): ≈ 0.65 – 0.80 Nm/A
Back-EMF Constant (Ke, line-line): ≈ 42–52 V/krpm (RMS)
Winding Resistance (Line-Line, 25 °C): ≈ 2.5 – 4.0 Ω
Winding Inductance (Line-Line): ≈ 8 – 15 mH
Rotor Inertia (without brake): ≈ 0.28 × 10⁻⁴ kg·m² (0.28 kg·cm²)
Brake Option: Not included in “-21” suffix (brake variants end in -Bxx)
Feedback Device (Factory-Fitted): Typically 2-pole resolver (standard on Goldline B); some shipped with incremental encoder — verify nameplate
Insulation Class: Class F (155 °C), 100 K temp rise above 40 °C ambient
Protection Class: IP65 (shaft seal + O-ring on connector when mated)
Cooling: Natural convection (no fan)
Operating Temperature (Ambient): 0 °C to +40 °C rated; –20 °C to +55 °C with derating
Housing Material: Black painted steel lamination stack; cast aluminum end bell; Neodymium-Iron-Boron (NdFeB) magnets
Connector Type: Circular military-style or Hirschmann multi-pin (power + feedback)
Compliance: cURus, CE
Applicable Industries: Packaging machinery (form-fill-seal, cartoners), printing press register axes, pick-and-place units, textile yarn guides, woodworking CNC auxiliary axes
Installation Requirements: Flange-mount on machined NEMA 34 pattern; align load coupling coaxially (max. overhung radial load ~110 N at shaft end); torque mounting bolts to spec; connect PE; use shielded feedback cable with shield grounded at drive end only.
Usage Notes: Goldline B series is discontinued — AKM series (AKM6x) is the functional replacement; verify feedback type matches drive before commissioning; resolver feedback auto-commutated by modern Kollmorgen drives via motor ID; thermal time constant ~20 min — respect continuous torque limit in sustained duty.
