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Phone: +86 16626708626Description
3. Key Technical Specifications
| Parameter | Value |
|---|---|
| Nominal current | 7 A |
| Maximum current | 28 A |
| Nominal power | 1,600 VA |
| Intermediate circuit voltage | 280–370 VDC |
| Output voltage (3-phase) | 0–230 VAC |
| Output frequency | 0–667 Hz |
| Motor rotational speed | Up to 20,000 min⁻¹ |
| Control voltage | +24 V |
| Processor voltage | +5 V |
| Protection class | IP20 |
| Ambient temperature | 0–55 °C (with ventilator) |
| Max. motor cable length | 100 m |
| Interference suppression | EN 55011 Class A |
| Weight | Approx. 2.7–3.5 kg |
4. Product Introduction
The Bosch Rexroth Indramat LT304 is a servo amplifier designed for precise control of AC servo motors in industrial automation, CNC machines, and robotics. It operates from a 280–370 VDC intermediate circuit and delivers three-phase output from 0 to 230 VAC at frequencies up to 667 Hz.
Digital signal processing enables accurate speed, position, and torque control with high dynamic response. The unit mounts in system boxes or card racks, supports motor cable lengths up to 100 m, and includes built-in diagnostics. Confirm exact firmware version, intermediate-circuit voltage, and motor compatibility against the OEM documentation before installation.
LT304
LT304
5. Troubleshooting Quick Reference
| Symptom | Possible Cause | Relevance to this Part | Quick Check Method | Recommendation |
|---|---|---|---|---|
| No output / motor does not turn | Intermediate circuit voltage missing or out of range | ✅ High | Measure DC link voltage (must be 280–370 VDC) | Verify supply module and fuses first |
| Overcurrent fault | Motor cable short, incorrect motor parameters, or overload | ✅ High | Inspect motor cable insulation and measure phase-to-phase resistance | Check cable length ≤100 m and motor data match |
| Overtemperature | Insufficient cooling or ambient >55 °C | ✅ Medium | Confirm fan operation and cabinet temperature | Improve ventilation; derate if needed |
| Communication / control loss | +24 V control supply missing or faulty interface | ❌ Low | Measure +24 V and +5 V processor voltages | Check external control power and connectors |
| Erratic speed or positioning | Feedback device fault or parameter mismatch | ✅ Medium | Verify encoder/resolver signals and parameter set | Reload correct motor parameters; test feedback |
If the fault persists after these checks, record the exact error code, LED status, and intermediate-circuit voltage, then contact technical support with photos and diagnostic data.
6. Frequently Asked Questions (FAQ)
Q: Is the LT304 new original or refurbished?
A: This listing is New Original (New Surplus). The unit has not been previously installed in a production system. We perform visual inspection, power-on verification of the intermediate circuit and control voltages, and basic functional checks before shipment.
Q: What is the nominal and peak current rating?
A: Nominal current is 7 A. Maximum (peak) current is 28 A. Continuous power is rated at 1,600 VA. Do not exceed these values under continuous or intermittent duty.
Q: Can I use motor cables longer than 100 m?
A: The maximum specified motor cable length is 100 m. Longer cables increase capacitance and can cause overcurrent trips or instability. Use only shielded cables rated for the application and keep length within limit.
Q: What cooling is required?
A: Ambient temperature must stay between 0 °C and 55 °C with forced ventilation (ventilator). Operation without adequate airflow will trigger thermal protection and reduce service life.
Q: Does the LT304 support position, speed, and torque control?
A: Yes. The DSP-based controller supports position, speed, and torque modes. Exact mode availability and parameter structure depend on the connected control system and firmware version. Verify the parameter set matches the motor and application.
Q: What is the typical lead time and warranty?
A: Stock units typically ship within a few business days after payment confirmation. Warranty is 1 year against manufacturing defects under normal operating conditions within the specified ratings.
