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Kollmorgen B-204-B-21-B2
Model Series: B-Series (Brushless Commutated Servo Motor)
Product Overview:
High-performance brushless DC servo motor designed for demanding motion control applications requiring high torque density and precise positioning. Features commutated construction with integrated feedback.
Detailed content
Technical Specifications:
| Parameter | Value |
|---|---|
| Frame Size | 204 (115mm Flange) |
| Motor Length | Standard B-204 stack length |
| Winding Code | B-21 |
| Option Code | B2 (Holding Brake Included) |
| Continuous Torque | 2.7 Nm (at 25°C case temp) |
| Peak Torque | 8.1 Nm |
| Max Speed | 4,500 RPM |
| Rated Voltage | 48–325 VDC (winding dependent) |
| Encoder Type | 17-bit Multi-turn Absolute (Hiperface DSL) |
| Encoder Resolution | 131,072 counts/rev (single-turn) |
| Brake Type | 24 VDC Spring-Applied Holding Brake |
| Brake Torque | 7.5 Nm |
| Motor Weight | Approx. 3.2 kg (with brake) |
| Insulation Class | Class H (180°C) |
| Protection Rating | IP65 (with connector) |
Material Composition:
- Stator: Laminated silicon steel (M-19 grade)
- Rotor: Samarium Cobalt (SmCo) permanent magnets
- Housing: Anodized aluminum alloy (6061-T6)
- Shaft: Hardened stainless steel (17-4PH)
- Brake: Spring steel with copper winding
Structural Features:
- Flange-mount design with bolt pattern for rigid coupling
- Integrated single-cable connection (motor + brake + encoder)
- Pre-loaded angular contact ball bearings
- Labyrinth seal for contamination protection
Working Principle:
Electronic commutation replaces mechanical brushes. Hall sensors detect rotor position; drive electronics sequentially energize stator windings to produce rotating magnetic field. Multi-turn absolute encoder provides position feedback for closed-loop servo control. Holding brake engages via spring force when de-energized, releases at 24VDC.
Key Advantages:
- High torque-to-inertia ratio for fast acceleration
- 17-bit absolute encoder eliminates homing routine
- Integrated brake for vertical axis safety
- Wide voltage range (48–325VDC) for flexible system design
- Commutated design provides smooth torque with low cogging
Applicable Industries:
- CNC machine tools
- Packaging machinery
- Printing presses
- Material handling systems
- Robotics (medium-payload)
Installation Requirements:
- Mount on flat surface with M6 through-bolts, torque to 12 Nm
- Alignment tolerance: ≤ 0.05mm TIR
- Ambient temperature: -20°C to +50°C (derate above 40°C)
- Ensure adequate ventilation; minimum 100mm clearance on all sides
Usage Precautions:
- Do not exceed continuous torque rating to prevent thermal damage
- Brake voltage must be 24 VDC ±10%; overvoltage causes brake burnout
- Do not disassemble encoder section; contamination voids warranty
- Use only Kollmorgen-approved cables for encoder and power connections
