Description
Hard-Numbers: Technical Specifications
- Continuous Output Current: 30A rms (3-phase sinusoidal current)
- Peak Output Current: 90A rms (for 10 ms)
- Input Voltage: 380–480VAC 3-phase (400V nominal); accepts ±10% variation
- Input Frequency: 50/60Hz
- Max Output Voltage: ~85% of input line voltage (vector mode)
- Supported Motor Types: Kollmorgen AKM series servo motors (400V)
- Feedback Interfaces:
- Absolute and incremental encoders (Heidenhain EnDat, Siemens, Fanuc protocols)
- Resolvers, SinCos encoders, BiSS interface
- Control Modes: Position, velocity, torque, camming, gearbox emulation
- Current Loop Bandwidth: >1 kHz typical (vector mode)
- Position Loop Bandwidth: >200 Hz typical
- Integrated Safety: STO (Safe Torque Off) per IEC 61508 (SIL 3)
- Encoder Resolution: Up to 23 bits (absolute) or 16,384 counts/rev (incremental)
- Operating Temperature: 0°C to +50°C ambient (de-rate above 40°C)
- Storage Temperature: -25°C to +85°C
- Humidity: 10–90% RH non-condensing
- Power Consumption: ~3–5 kW at full load (varies with motor size)
- Certifications: CE, UL, CSA, IEC 61800-5-1 (EMC), IEC 61508 (STO)
- Dimensions: 400 mm × 150 mm × 200 mm (15.7″ × 5.9″ × 7.9″) with mounting brackets
- Mounting: DIN rail or panel mount
KOLLMORGEN S72402-NANANA
The Real-World Problem It Solves
High-power motion control applications (large injection molding machines, heavy material handling, packaging lines) need servo drives capable of driving 400V motors with continuous high current. Low-power or 230V drives can’t deliver sufficient torque for heavy loads or achieve the dynamic performance required for high-throughput production. The S72402-NANANA delivers 30A continuous current with 90A peak current, supporting Kollmorgen AKM 400V servo motors up to ~30 kW power rating. Its digital vector control ensures tight current regulation, low-speed torque, and rapid response for demanding motion profiles.
Where you’ll typically find it:
- Large injection molding machines with clamp units requiring high torque
- Heavy-duty packaging lines and palletizers with high dynamic requirements
- Industrial robots and material handling equipment with payloads >100 kg
- Presses and forming machinery with precise positioning requirements
Bottom line: The S72402-NANANA is the powerhouse for 400V servo systems—high current, high voltage, and integrated safety for heavy-duty motion control.
Hardware Architecture & Under-the-Hood Logic
The S72402-NANANA is a 400V digital servo amplifier designed for high-power single-axis motion control in the Kollmorgen S700 series. It accepts 380–480VAC 3-phase input, generates a sinusoidal PWM output for the 400V servo motor, and integrates with encoder feedback to close the current, velocity, and position loops. The architecture is similar to the S71201-NA but scaled for 400V operation and higher current output.
-
Power Input Stage: The 3-phase input goes through EMI filtering, a bridge rectifier, and bulk capacitors to generate a smooth DC bus voltage (~650VDC from 400VAC). The DC bus voltage is monitored continuously—if it drops below threshold (e.g., due to input undervoltage), the drive goes into fault mode. Overvoltage protection clamps the DC bus to limit peak voltages during regenerative braking.
-
Motor Drive Stage: The DC bus voltage is converted to 3-phase PWM output using IGBTs rated for 600V operation. The IGBTs switch at ~8 kHz (variable) to create a sinusoidal output current. A current sensor in each phase monitors output current for vector control and overcurrent protection. Vector control uses SVPWM to deliver optimized current waveform to the motor, minimizing torque ripple even at low speeds.
-
Digital Control Logic: A 32-bit DSP processor handles real-time servo loops at higher bandwidths than 230V drives:
- Current Loop: Faster than 1 kHz loop closure for precise current regulation. The current sensor feedback is processed, and error compared to current reference generates PWM duty cycle.
- Velocity Loop: ~100–200 Hz loop closure uses encoder feedback to regulate motor speed, compensating for load changes.
- Position Loop: ~50–100 Hz loop closure uses encoder encoder feedback to regulate position, ensuring the motor follows commanded profiles accurately.
- Safety Logic: Hardware-implemented STO (Safe Torque Off) per IEC 61508 SIL 3. When STO is activated, the drive immediately disconnects power to the motor stator by switching off all IGBTs.
-
Feedback Interface: The drive supports multiple feedback types for 400V applications: absolute encoders (EnDat, SSI), resolvers, SinCos encoders, and BiSS interface. The feedback interface processes encoder signals to provide velocity and position feedback for closed-loop control. For absolute encoders, position is available at power-up without homing.
-
Dynamic Braking Regeneration: When the motor operates in regenerative mode (coasting or decelerating), kinetic energy is converted back into electrical energy, charging the DC bus. If the DC bus voltage exceeds the regenerative braking threshold, the drive uses a braking resistor (external or internal option) to dissipate excess energy, preventing overvoltage fault.
-
Front-Panel Interface: The drive features a backlit LCD panel and keypad for parameter configuration, fault monitoring, and diagnostic data. Parameters include motor type, feedback type, control mode, loop gains, and dynamic braking configuration. The panel displays current status words, actual values (position, velocity, torque), and fault codes with descriptions.
KOLLMORGEN S72402-NANANA
Field Service Pitfalls: What Rookies Get Wrong
Using 230V Motors on a 400V Drive
I’ve seen techs install a 230V AKM motor on an S72402-NANANA (400V drive) because they think “it will work with lower voltage.” The drive outputs ~85% of input line voltage—~340VAC phase-to-phase for a 400V input. This is significantly higher than a 230V motor’s rated voltage (~200VAC phase-to-phase). The motor insulation may be overstressed, leading to premature winding failure or immediate short circuit.
- Field Rule: Never connect a 230V motor to a 400V drive. Use S72402-NANANA (400V input) for 400V AKM motors, and S71201-NA (230V input) for 230V AKM motors. Verify motor nameplate voltage before connecting—mismatching is a safety hazard and voids warranty.
Undersizing Braking Resistors for High-Inertia Loads
In applications with high inertia and rapid deceleration, regenerative energy can exceed the braking resistor’s power rating. Rookies install a standard 100W braking resistor on a system that generates 500W during deceleration. The resistor overheats, may catch fire, or fails open-circuit—causing DC bus overvoltage fault and uncontrolled motor coasting.
- Quick Fix: Calculate regenerative braking power required for the worst-case deceleration. Use Kollmorgen’s WorkBench software or manual calculation to determine resistor power rating. For high-inertia loads, consider a braking chopper unit or regenerative braking module to feed energy back to the grid. Install the resistor with adequate ventilation and thermal protection.
Overlooking Input Filter Requirements at 400V
The S72402-NANANA generates significant harmonic distortion and EMI at 400V operation. Rookies omit the input EMI filter recommended by Kollmorgen for 400V drives. This causes conducted EMI to affect nearby equipment and may violate CE/UL EMI compliance. In severe cases, EMI interferes with encoder feedback, causing position instability.
- Field Rule: Install the Kollmorgen-recommended input EMI filter (EMC filter) for 400V drives. Mount the filter as close to the drive input terminals as possible. Connect the filter’s ground plane to the drive’s PE terminal and verify proper grounding per manufacturer guidelines. Test EMI levels with a spectrum analyzer if EMI issues are suspected.
Ignoring Grounding Requirements for 400V Systems
400V drives require robust grounding to ensure safety and EMI control. New engineers use undersized grounding cables or connect the drive chassis to signal ground instead of safety ground. Poor grounding at 400V creates hazardous touch voltages and causes motor current ripple or erratic behavior.
- Field Rule: Use a grounding cable with cross-section at least 10 mm² (6 AWG) for the main ground connection. Connect the drive’s PE terminal to the equipment’s safety ground bus, not signal ground. Use separate grounding cables for motor and encoder to avoid ground loops. Verify resistance between drive chassis and safety ground is <1Ω using a low-resistance ohmmeter.
Neglecting DC Bus Precharge Circuit Check
The S72402-NANANA has a DC bus precharge circuit that limits inrush current during power-up. If this circuit fails (e.g., a precharge relay sticks open), the drive may not charge the DC bus properly, resulting in a “DC bus undervoltage” fault at startup. Rookies assume the drive is defective but don’t check the precharge relay.
- Field Rule: Monitor drive behavior at startup. The drive should complete precharge within 2–3 seconds, then indicate “Ready.” If the drive immediately faults on DC bus undervoltage or takes >10 seconds to charge, check the precharge relay operation with a multimeter—measure voltage across the precharge resistor during startup (should be present briefly, then drop to zero as relay closes). Replace the precharge relay if it fails to close.
Failing to Test STO Functionality at 400V
STO (Safe Torque Off) is mandatory for emergency 终止 circuits. At 400V, the energy stored in the DC bus is significantly higher than at 230V. Rookies test STO by opening the input circuit but don’t verify that torque output is actually removed. The STO circuit may have failed internally, but the drive still outputs torque because the DC bus retains charge.
- Field Rule: Test STO functionality with the drive under load. Activate STO and verify that motor 终止s with no torque output within 10 ms. Use a torque sensor or current clamp to confirm motor current drops to zero. Verify the STO LED illuminates on the drive front panel. Document STO test results in safety procedures—400V STO failures can be catastrophic.
Commercial Availability & Pricing Note
Please note: The listed price is for reference only and is not binding. Final pricing and terms are subject to negotiation based on current market conditions and availability.
