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Kollmorgen S77202-NANANA
Product Series: S77202 (AKD Drive Braking Resistor Assembly)
Product Introduction:
The S77202-NANANA is a braking resistor assembly designed for use with Kollmorgen AKD-series servo drives. It dissipates regenerative energy generated during motor deceleration, preventing DC bus overvoltage faults. The “NANANA” suffix indicates the standard / default configuration with no special options selected.
Detailed content
Model Breakdown:
- S77202 = Product Family (Braking Resistor for AKD Drives)
- NANANA = Configuration: Standard — No Options (Default)
Technical Specifications:
| Parameter | Value |
|---|---|
| Compatible Drive Series | Kollmorgen AKD-B, AKD-P Series |
| Resistance Value | 20 Ω (typical for 48A drives) |
| Power Rating | 800W Continuous / 2,400W Peak (10 sec) |
| Enclosure Type | Aluminum Heat-Sink Housing (IP20) |
| Operating Temperature | -10°C to +60°C |
| Dimensions (W×H×D) | Approx. 180mm × 120mm × 80mm |
| Weight | Approx. 2.5 kg |
| Connection | Screw terminals (2-wire to AKD drive TB2) |
| Certifications | UL Listed, CE, C-UL |
Functional Features:
- Automatic activation when DC bus voltage exceeds 380V (configurable threshold).
- Thermal protection — resistor shuts down at 150°C surface temperature.
- No external power supply required — powered directly from the drive’s DC bus.
- Plug-and-play — connects directly to AKD drive braking resistor terminals.
Working Principle:
During motor deceleration, the motor acts as a generator, feeding energy back into the DC bus. When bus voltage rises above the braking threshold, the AKD drive switches an internal IGBT to connect the braking resistor across the DC bus. The resistor converts the excess electrical energy into heat, which is dissipated through the aluminum fins. When bus voltage drops below the threshold, the IGBT turns off.
Applicable Industries:
- Vertical axis motion (Z-axis on CNC machines)
- High-inertia load deceleration
- Overhauling loads (cranes, hoists)
- Rapid cycling applications (pick-and-place)
Installation Requirements:
- Mount in a well-ventilated area — minimum 100mm clearance on all sides.
- Connect to AKD drive TB2 terminals (Brake+ / Brake-).
- Use wire gauge per AKD manual: minimum 4mm² for 48A drives.
- Do not install near flammable materials — resistor surface reaches high temperatures.
Usage Precautions:
- Do not bypass the braking resistor — risk of DC bus overvoltage and drive fault.
- Do not touch the resistor during or immediately after operation — surface temperature exceeds 100°C.
- Ensure ambient temperature does not exceed 60°C — derate power by 2% per °C above 40°C.
- Clean dust from heat sink fins regularly — dust reduces cooling efficiency.
