Description
Key Technical Specifications
| Parameter | OEM specification |
|---|---|
| Operating voltage | 24 VDC (+40% / -20%) |
| Permitted operating range | 18–35 VDC |
| Power consumption | Less than 50 VA |
| Current consumption | Less than 2 A |
| Fuse | 2 A, medium time-lag |
| Analog voltage inputs | 0 to ±10 VDC |
| Analog current input | 4–20 mA |
| Current input load | 100 Ω |
| Solenoid output current | 0–2.5 A |
| Output protection | Short-circuit protected |
| Ramp time | 20 ms–5 s or 0.2–50 s |
| Digital functions | Enable, ramp on/off, command selection, inversion |
| Ready output | Greater than 16 V, 50 mA |
| Connector | 48-pin DIN 41612, design F |
| Card dimensions | 100 × 160 mm |
| Operating temperature | 0 to +50°C |
| Storage temperature | -25 to +85°C |
| Net weight | Approximately 0.17 kg |
Product Introduction
The Bosch Rexroth R901002090 VT-VSPA2-1-2X/V0/T1 is an analog amplifier card for electrohydraulic proportional valve control. It processes voltage or current command signals from a PLC, CNC controller, or other supervisory control equipment and generates regulated current for the proportional valve solenoid. The card includes command-value summation, zero-point adjustment, signal inversion, characteristic-curve correction, and output-current monitoring.
The T1 configuration has one adjustable ramp generator. This function controls how quickly the output current changes when the command signal changes, reducing abrupt hydraulic movement during machine acceleration, deceleration, and directional transitions. The amplifier also provides an enable input and a ready-for-operation output. Its Eurocard construction allows installation in the specified Rexroth card holder rather than direct mounting as a standalone DIN-rail module.
R901002090 VT-VSPA2-1-20V0T1
Application Scenarios & Field Pitfalls
Typical applications
- Hydraulic directional control on CNC machine tools.
- Proportional flow and pressure regulation.
- Injection molding machine hydraulic circuits.
- Industrial presses and clamping systems.
- Automated machinery using Rexroth 4WRA or 4WRZ proportional valves.
Important engineering checks
- Valve matching: Verify the complete valve designation. The amplifier is documented for 4WRA 6/10 series 2X, 4WRZ series 7X, and 3DREP 6 series 2X. A similar-looking valve from another series may require different amplifier settings.
- Input signal: The card supports ±10 V differential input and 4–20 mA current input. Check the PLC analog output configuration, signal reference, and wiring before commissioning.
- Output current: The power stage supports up to 2.5 A. Confirm the valve coil requirements rather than assuming every compatible valve operates at the maximum current.
- Ramp adjustment: T1 supports a single ramp time, selectable between 20 ms–5 s and 0.2–50 s through jumper configuration. Incorrect settings can cause sluggish response or abrupt hydraulic movement.
- Characteristic curve settings: Zero adjustment, step level, and positive/negative amplitude settings affect valve behavior. Preserve the original machine settings when replacing a failed card.
- Installation: Use the specified 48-pin card holder and install the amplifier inside a suitable control cabinet.
Related Products
| Model / part number | Description | Relationship |
|---|---|---|
| R901002090 | VT-VSPA2-1-2X/V0/T1 | Single-ramp amplifier |
| R901002095 | VT-VSPA2-1-2X/V0/T5 | Five-ramp amplifier variant |
| R900020154 | VT3002-1-2X/48F | Compatible open card holder |
| VT 3000-3X | Earlier amplifier family | Documented replacement consideration, subject to conversion instructions |
Important: R901002095 is not automatically interchangeable with R901002090. The T5 version has different ramp-selection and measurement functions. Earlier amplifier replacements may also require configuration changes and specific jumper settings.
Procurement and Quality Control
For replacement purchasing, use the complete designation:
Bosch Rexroth R901002090 – VT-VSPA2-1-2X/V0/T1
Before accepting the card, verify:
- Material number and complete model code on the label.
- PCB revision and connector condition.
- Fuse rating and power-supply behavior.
- Analog input response at representative command values.
- Solenoid output-current regulation.
- Enable and ready-for-operation signals.
- Ramp adjustment and output-stage fault monitoring.
For used or surplus stock, request actual test records. A card that powers up successfully has not necessarily passed output-current regulation or proportional-valve control testing.
Replacement recommendation: Match the R901002090 T1 configuration and preserve the original jumper settings and calibration values. In hydraulic machinery, incorrect ramp or current settings can produce unexpected actuator movement even when the amplifier itself is electrically functional.
