Description
Bosch Rexroth LT304 | 0 608 750 085 Drive Module
Product Introduction
The Bosch Rexroth LT304 is a legacy servo amplifier used in the BT300 tightening system. It controls an EC motor, with control parameters transmitted digitally from the system electronics (SE) to the LT amplifier. The LT304 is intended for rack installation—not as a standalone drive that can be wired into an arbitrary motor application.
Rexroth documentation identifies order number 0 608 750 085 for the LT304. Its published electrical data includes a 280–370 VDC intermediate circuit, three-phase motor output up to 230 VAC, and 7 A nominal output current. This is a configuration-specific industrial drive component, so verify the BT300 rack, system electronics, motor, and parameter setup before treating a surplus module as a replacement.
LT304
Key Technical Specifications
- Model: LT304
- Rexroth Order Number: 0 608 750 085
- Manufacturer: Bosch Rexroth
- Product Category: Servo amplifier
- System: BT300 tightening system
- Intermediate-Circuit Voltage: 280–370 VDC
- Control/Logic Supplies: +24 V and +5 V, supplied within the system architecture
- Motor Output Voltage: Three-phase, 0–230 VAC
- Output Frequency: 0–667 Hz
- Nominal Output Current: 7 A
- Maximum Output Current: 28 A
- Maximum Motor Speed: Up to 20,000 rpm, depending on the motor configuration
- Nominal Output Power: 1,600 VA
- Maximum Motor Cable Length: 100 m
- Operating Temperature: 0°C to +55°C with ventilator
- Relative Humidity: 20–90%, non-condensing during operation
- Protection Class: Class I protective earthing for the servo amplifier; SELV for logic
- Enclosure Protection: IP20 when installed
- Dimensions: Approximately 46 × 271 × 285 mm
- Weight: Approximately 2.7 kg
Specifications are drawn from Rexroth LT30x documentation. Confirm the applicable manual revision and exact nameplate before commissioning.
Global Sourcing & Live-Test SOP
5.1 Inbound Verification
- Photograph the complete LT304 nameplate and order number.
- Confirm 0 608 750 085 and distinguish from LT303 or LT305.
- Inspect the card-rack interface, connectors, and retaining hardware.
- Check for corrosion, heat discoloration, cracked housings, or signs of repair.
- Record serial number and available manufacturing or revision data.
- Confirm whether the module is supplied alone or with any rack, wiring, or system electronics.
5.2 Electrical and Physical Inspection
- Inspect the module for visible damage before installation.
- Verify that the intended BT300 rack and system configuration are compatible.
- Confirm the required power and grounding arrangement from the Rexroth documentation.
- Do not apply external power to unidentified pins or connectors.
- Check connector seating and rack alignment before energizing.
5.3 Controlled Functional Test
- Test only in a compatible BT300 system or an approved test fixture.
- Verify system-electronics communication and module recognition.
- Confirm motor and drive parameter compatibility.
- Perform initial operation with appropriate mechanical safeguards and controlled limits.
- Monitor drive faults, current behavior, motor response, and abnormal noise.
- Record the rack, system-electronics module, motor, and parameter configuration used during testing.
5.4 Extended Run and Final Preparation
- Run the module under controlled conditions appropriate to the installed motor and application.
- Monitor temperature, fault status, current, and communication stability.
- Record test duration, system configuration, and observed results.
- Protect the rack connector and module edges during shipment.
- Use ESD-safe packaging and suitable cushioning.
- Describe the unit as tested, untested, refurbished, or as-is according to the actual inspection performed.
Field Engineer’s Pitfall Guide
❗ is a BT300 rack module—not a general-purpose standalone servo drive
The is documented for installation in the card-rack and operation with the system electronics. Do not assume it can be commissioned independently of the intended rack and control architecture.
❗ Do not confuse nominal current with maximum current
Rexroth lists 7 A nominal output current and 28 A maximum output current. These values describe different operating limits; the maximum figure should not be treated as a continuous rating. Confirm applicable duty and motor limits in the original documentation.
❗ Verify the exact LT-series order number
The LT303, , and LT305 are different amplifier modules with different current and application capabilities. Match 0 608 750 085 and the original machine configuration rather than substituting by family name alone.
Intent-Driven FAQ
What is the Bosch Rexroth ?
The is a servo amplifier used in the tightening system to control an EC motor.
What is the Rexroth order number?
The documented order number is 0 608 750 085.
What is the nominal output current?
Rexroth documentation lists 7 A nominal output current and 28 A maximum output current. These ratings should be interpreted in accordance with the original drive documentation and operating conditions.
Can the operate as a standalone drive?
It is designed for installation in the card-rack and operation within that system architecture. Do not assume standalone compatibility.
Is the obsolete?
Radwell lists the Bosch Rexroth as discontinued by the manufacturer. Surplus availability and condition will vary by supplier.
Can an LT303 or LT305 replace an ?
Not automatically. These are separate amplifier models with different output-current and application ratings. Confirm the original system design and Rexroth documentation before considering substitution.
What should buyers verify before purchasing?
Confirm the exact model and order number, rack compatibility, connector condition, serial/revision details, seller test status, and whether any additional hardware is included.
Bottom Line for Buyers
The Bosch Rexroth (0 608 750 085) is a legacy servo amplifier with a 7 A nominal output-current rating, designed for rack-based EC motor control.
For replacement procurement, verify the order number, rack compatibility, system-electronics interface, and motor configuration. A matching LT-series label alone is not sufficient to establish a safe or functional replacement.
