Rexroth LT304

Core Technical Performance Parameters

1. Power Supply Specifications
   • Intermediate Circuit DC Voltage: 280 VDC ~ 370 VDC
   • Control Logic Power: 24 VDC ±10%
   • Processor Core Supply: 5 VDC internal regulated
   • Three-phase Motor Output: 0 ~ 230 VAC
2. Drive Electrical Ratings
   • Rated Output Current: 7 A
   • Peak Overload Current: 28 A
   • Max Output Frequency: 0 Hz – 667 Hz
   • Support Motor Max Speed: 20,000 RPM
   • Rated Power Capacity: 1600 VA
   • Maximum Motor Cable Length: 100 m
3. Signal I/O Specifications
   • Analog Input Range: 0–10 V, 0–32 V voltage; 0–20 mA current; 0–10 kHz frequency signal
   • Special Sensor Input: Compatible with DSM1-10 speed sensor (700–2000 Ω resistance signal)
   • PWM Proportional Coil Output with temperature & voltage compensation
   • Digital Switch Inputs with overvoltage short-circuit protection
4. Environmental Parameters
   • Operating Temp (with cooling fan): 0 °C ~ +55 °C
   • Storage Temp: -20 °C ~ +70 °C
   • Relative Humidity: 20% – 95% RH non-condensing
   • Product Net Weight: 2.7 kg

Material Composition

• Module Frame: Cold-rolled steel sheet with electrostatic anti-rust paint coating
• PCB Substrate: High TG FR4 flame-retardant circuit board with full conformal coating
• Terminal Base: High-temperature PA66 glass fiber reinforced plastic
• Power Connector Copper Terminals: Tin-plated oxygen-free copper (low impedance)
• Heat Sink: Extruded aluminum alloy with black oxidation anti-corrosion layer
• Front Operation Panel: Impact-resistant ABS plastic with transparent polycarbonate display window

Structural Characteristics

1. Standard rack-mounted vertical plug-in module structure, compatible with Rexroth 30 series control cabinet backplane bus
2. Front panel integrated digital status display, multi-function adjustment potentiometers, LED fault diagnostic indicators
3. Left side multi-row spring-cage wiring terminals for analog signals, digital I/O and proportional valve coils
4. Rear golden finger backplane connector for power supply, bus communication and multi-module synchronization signal
5. Built-in independent aluminum heat sink with vertical air convection channel for power tube heat dissipation
6. Internal multi-stage EMC filter circuit to suppress power grid harmonic interference

Working Principle

1. Upper PLC sends analog setpoint signal (0–10 V / 4–20 mA) or digital bus command to LT304 input terminal.
2. 32-bit triple-core processor samples feedback signals from motor encoder / hydraulic displacement sensor in real time, calculates deviation between target value and actual feedback value.
3. Internal PID adaptive algorithm automatically adjusts gain parameters, outputs high-frequency PWM pulse signal to power drive circuit.
4. Power module converts DC intermediate circuit voltage into 3-phase variable-frequency AC to drive servo motor, or outputs compensated PWM current to control proportional hydraulic valve spool displacement.
5. Built-in fault detection circuit monitors overcurrent, overvoltage, overheating, wire breakage and short-circuit conditions, locking output and triggering front-panel alarm indicator upon fault occurrence.

Installation Requirements

1. Install inside standard industrial electrical cabinet with mandatory cooling fan; maintain 20 mm vertical clearance above/below module for air circulation
2. Rack backplane must match original Rexroth LT30 series bus interface; mixed third-party backplanes prohibited
3. Shielded twisted-pair cable required for analog sensor wiring; cable shielding single-point grounded at cabinet ground bar
4. Power cable cross-section ≥1.5 mm² copper wire; separate wiring channel for power lines and signal lines to avoid crosstalk interference
5. Mount vertically only; horizontal installation will block heat sink airflow and cause overheating protection
6. Ground wire connected to cabinet PE protective ground terminal with resistance <0.4 Ω

Function & Feature Highlights

1. Triple-core high-speed processor, microsecond-level closed-loop response for ultra-precise motion control
2. Adaptive vibration suppression algorithm eliminates mechanical resonance of hydraulic / servo transmission systems
3. Full fault self-diagnosis: wire breakage, short circuit, overheat, phase loss, encoder failure, power undervoltage detection
4. Multiple control modes: position closed-loop, speed closed-loop, torque closed-loop, proportional flow/pressure control for hydraulics
5. Integrated EMC electromagnetic compatibility filter, complies with IEC 61000-6-2 industrial anti-interference standard
6. Multi-module synchronous bus communication for multi-axis coordinated linkage control
7. Adjustable dead zone compensation minimizes hydraulic valve hysteresis error

Typical Application Scenarios

• High-precision CNC milling, grinding, turning machine servo drive control
• Injection molding machine hydraulic proportional pressure/flow valve control
• Metal stamping, forging hydraulic press closed-loop motion system
• Automated metal cutting, laser cutting equipment feeding servo axes
• Packaging machinery multi-axis synchronous servo positioning
• Hydraulic test bench proportional valve precise drive unit

Operation & Maintenance Precautions

1. Cut off main cabinet power supply for 5 minutes before disassembly to discharge intermediate circuit high-voltage capacitance
2. Do not touch rear golden finger backplane connector with bare hands to prevent electrostatic damage to internal chips
3. Monthly clean heat sink dust with compressed air; dust accumulation causes overheating shutdown
4. Annual calibration of analog input zero offset and proportional coil output gain via front panel potentiometers
5. Prohibit operation beyond rated current; long-term overload will burn internal power transistors
6. Avoid installation in environments with oil mist, conductive dust or water vapor condensation
7. Store spare modules in dry constant-temperature cabinet with anti-static foam packaging