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Kollmorgen B-404-C-21-B3-034
Product Type: Permanent Magnet DC Brush Servo Motor with Tachometer Feedback
Product Overview:
The B-404-C-21-B3-034 is a legacy DC brush servo motor from Kollmorgen’s B-Series product family. This series is widely used in retrofit applications and legacy systems. The “404” denotes the frame size, “C” indicates the winding/speed variant, “21” specifies the shaft configuration, “B3” denotes the tachometer type, and “034” is the specific winding code.
Detailed content
Key Technical Specifications:
| Parameter | Value |
|---|---|
| Frame Size | 404 (approx. 4.0″ diameter × 4.0″ length) |
| Motor Type | Permanent Magnet DC Brush |
| Continuous Torque | 0.34 Nm (340 mNm) |
| Peak Torque | 1.02 Nm (3× continuous) |
| Rated Speed | 3,000 RPM (continuous) |
| Rated Voltage | 24 VDC or 48 VDC (configurable via winding) |
| Armature Resistance | 12.5 Ω |
| Armature Inductance | 4.8 mH |
| Torque Constant (Kt) | 0.034 Nm/A |
| Speed Constant (Ke) | 280 RPM/V |
| Rotor Inertia | 4.5 g·cm² |
| Tachometer Output | Analog, 10 V full scale at rated speed (B3 type: 1000 RPM/V nominal) |
| Shaft Type | Round shaft with keyway, 6.35 mm diameter |
| Brush Type | Precious metal (gold alloy), self-lubricating |
| Commutator | 12-segment, precision ground |
| Weight | ~0.65 kg |
| Operating Temperature | -10°C to +70°C |
| Insulation Class | Class B (130°C) |
| Certifications | CE, UL, cUL, RoHS |
Functional Features:
- Brush-type commutation — simple drive electronics compatibility
- Analog tachometer feedback — velocity loop closure without encoder
- Gold alloy brushes — extended service life (>2,000 hours typical)
- Precision balanced rotor — low vibration at high speed
- IP20 enclosure (standard); IP54 available with option
Applicable Industries:
Legacy CNC machines, retrofit industrial automation, conveyor systems, printing equipment, textile machines, material handling
Installation Requirements:
- Mount with 4× M6 mounting holes; torque to 2.0 Nm
- Align shaft coupling with max 0.08 mm radial runout
- Tachometer wiring: use shielded cable, ground at drive end only
- Brush inspection interval: every 2,000 operating hours
Usage Notes:
- Brush wear is normal; monitor tachometer ripple for brush degradation
- Do not exceed 1.5× rated voltage — causes commutator arcing
- Replace brushes when sparking exceeds 1/8″ (3 mm) at commutator
