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Kollmorgen B-604-B-A3
Overview:
The B-604-B-A3 is a dynamic braking resistor module from the Kollmorgen B-series product line, engineered to dissipate regenerative energy generated during motor deceleration or overhauling loads. The resistor converts excess kinetic energy into thermal energy, protecting the servo drive from DC bus overvoltage faults. The “B” suffix denotes the base configuration, and “A3” specifies the terminal/connector variant.
Detailed content
Key Specifications:
| Parameter | Value |
|---|---|
| Resistance Value | 4 Ω (±5%) |
| Rated Power (Continuous) | 600 W |
| Peak Power (10 seconds) | 1200 W |
| Maximum DC Bus Voltage | 565 VDC |
| Enclosure Material | Extruded Aluminum (anodized) |
| Cooling Method | Natural Convection (no fan) |
| Terminal Type | Screw terminals (A3 variant) |
| Operating Temperature Range | -20°C to +80°C |
| IP Rating | IP20 |
| Weight | Approximately 1.5 kg |
Material Composition:
- Resistor Element: Nickel-Chromium (NiCr) wire-wound on ceramic core
- Housing: Extruded aluminum alloy 6063-T5, anodized for corrosion resistance
- Terminals: Tin-plated copper with stainless steel screws
- Mounting Brackets: Galvanized steel
Structural Features:
- Rectangular aluminum housing with integrated mounting flanges
- Wire leads with pre-crimped ring terminals
- Clearance-optimized fin geometry for passive air cooling
- Vibration-resistant construction suitable for industrial cabinets
Working Principle:
During motor deceleration, the motor acts as a generator, feeding energy back into the DC bus of the servo drive. When the DC bus voltage exceeds a preset threshold (typically ~390–420 VDC for 240 VAC systems), the drive switches an internal IGBT to route current through the external braking resistor. The resistor converts electrical energy into heat, clamping the DC bus voltage to a safe level. The B-604-B-A3 is sized to handle the average regenerative power of medium-inertia loads.
Advantages:
- High thermal mass aluminum housing for sustained duty cycles
- Wide operating temperature range — suitable for harsh environments
- Direct compatibility with Kollmorgen S700 and AKD series drives
- No moving parts — zero maintenance, infinite service life
- Compact footprint — saves cabinet space
Applicable Industries:
CNC machining centers, vertical axis machines, hoists and cranes, conveyor systems, winding/unwinding equipment, elevator drives.
Installation Requirements:
- Mount in a location with unrestricted airflow (minimum 100 mm clearance on all sides)
- Do not install near heat-sensitive components
- Connect using the supplied cables — minimum wire gauge: 10 AWG (6 mm²)
- Ensure the resistor is grounded to the cabinet chassis
Usage Precautions:
- Surface temperature during operation can exceed 150°C — do not touch during or immediately after operation
- Verify resistance value matches the drive’s configured braking resistor setting
- For duty cycles exceeding 50% regeneration, consult Kollmorgen for a higher-rated resistor
- Do not operate with damaged housing or cracked resistor element
