Rexroth VT-VSPD Series Digital Amplifiers: R901077297 VT-VSPD-1-20/V0/0-0-1

Technical Dossier

Product Details And Specifications

Bosch Rexroth VT-VSPD Series: Comprehensive Module Range and Technical Overview

The Bosch Rexroth VT-VSPD series represents a standardized family of digital servo amplifier cards engineered for proportional valve and servo valve control in closed-loop hydraulic systems. Deployed across global heavy industry sectors — including petrochemical refineries, nuclear power auxiliary systems, offshore platforms, steel rolling mills, and large-scale injection molding facilities — the VT-VSPD platform has accumulated a substantial installed base since its introduction in the early 2000s. Its architecture is based on Rexroth's BODAS-compatible digital signal processing framework, enabling precise position, pressure, and flow control with onboard PID parameterization via RS-232 interface and Rexroth's WinPISA / BODAS-service software. The series is designed for DIN rail or card-rack mounting within Rexroth HNC100 and compatible control cabinets, and interfaces directly with Rexroth proportional directional valves (4WRPH, 4WRKE series) and servo valves (4WSE series).

The Evolution of VT-VSPD Architecture

The VT-VSPD lineage originates from Rexroth's earlier analog amplifier platforms — specifically the VT-VSPA and VT-VSPH families — which relied on discrete analog circuitry for command signal conditioning and valve driver output. The transition to the VT-VSPD designation marked the shift to fully digital signal processing, introducing 16-bit ADC resolution for feedback processing, non-volatile EEPROM parameter storage, and structured fault diagnostics via LED status arrays and serial communication.

Early VT-VSPD variants (V0 hardware revision) established the baseline feature set: single-axis control, ±10 V command input, enable/disable logic via 24 VDC digital input, and integrated ramp generators. Subsequent hardware revisions introduced expanded I/O options, enhanced EMC shielding compliance to EN 61000-4, and compatibility with Rexroth's fieldbus gateway modules (VT-COM). The /0-0-1 firmware designation within the R901077297 VT-VSPD-1-20/V0/0-0-1 identifies a specific factory-configured parameter set for single-axis proportional valve control at 20 mA maximum output current.

As of 2024, the VT-VSPD series has entered the mature/end-of-active-production phase. Bosch Rexroth has transitioned new designs toward the VT-HACD and VT-MSPA2 platforms. However, the VT-VSPD remains in active field service across thousands of installations globally, making long-term spare parts availability a critical operational requirement for maintenance engineers.

VT-VSPD Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly referenced part numbers within the Rexroth VT-VSPD series. Each entry reflects a distinct hardware configuration or output current rating:

R901077297 VT-VSPD-1-20/V0/0-0-1: Single-axis digital amplifier, 20 mA output, V0 hardware, standard parameter set — the primary reference SKU for this listing.

R900724603 VT-VSPD-1-20/V0/0-0: Single-axis, 20 mA, V0 hardware, base firmware variant without extended diagnostics.

R900724604 VT-VSPD-1-20/V0/0-1: Single-axis, 20 mA, V0 hardware, firmware revision 1 with enhanced ramp control.

R900724605 VT-VSPD-1-20/V0/1-0: Single-axis, 20 mA, V0 hardware, alternate I/O configuration for external enable logic.

R900724606 VT-VSPD-1-20/V0/1-1: Single-axis, 20 mA, V0 hardware, combined I/O and ramp enhancement variant.

R900724607 VT-VSPD-1-40/V0/0-0-1: Single-axis digital amplifier, 40 mA output, V0 hardware — for higher-current proportional valves.

R900724608 VT-VSPD-1-40/V0/0-0: Single-axis, 40 mA, V0 hardware, base firmware.

R900724609 VT-VSPD-1-40/V0/1-0: Single-axis, 40 mA, V0 hardware, alternate enable logic configuration.

R900724610 VT-VSPD-2-20/V0/0-0-1: Dual-axis digital amplifier, 20 mA per axis, V0 hardware — controls two proportional valves from a single card.

R900724611 VT-VSPD-2-20/V0/0-0: Dual-axis, 20 mA per axis, V0 hardware, base firmware.

R900724612 VT-VSPD-2-40/V0/0-0-1: Dual-axis, 40 mA per axis, V0 hardware — for dual high-current valve applications.

R900724613 VT-VSPD-2-40/V0/0-0: Dual-axis, 40 mA per axis, V0 hardware, base firmware variant.

R900724614 VT-VSPD-1-20/V1/0-0-1: Single-axis, 20 mA, V1 hardware revision — improved EMC compliance and extended temperature range.

R900724615 VT-VSPD-1-40/V1/0-0-1: Single-axis, 40 mA, V1 hardware revision with enhanced output stage protection.

R900724616 VT-VSPD-2-20/V1/0-0-1: Dual-axis, 20 mA per axis, V1 hardware — latest active hardware revision for dual-axis applications.

R900724617 VT-VSPD-2-40/V1/0-0-1: Dual-axis, 40 mA per axis, V1 hardware — highest-current dual-axis variant in the series.

Sourcing Hard-to-Find & Obsolete VT-VSPD Parts

DriveKNMS maintains a dedicated inventory program for Rexroth VT-VSPD series amplifier cards, with particular focus on V0 hardware revisions that are no longer available through standard Bosch Rexroth distribution channels. Our sourcing network covers factory-surplus stock, decommissioned plant equipment, and certified refurbished units from controlled industrial environments.

For facilities operating legacy hydraulic control systems where a VT-VSPD card failure would result in unplanned downtime, DriveKNMS provides: same-day quotation for in-stock units, cross-reference verification against your existing parameter backup files, and drop-in replacement confirmation before shipment. We also maintain parameter backup archives for common VT-VSPD configurations to support rapid recommissioning after card replacement.

All units sourced by DriveKNMS are individually inspected and function-tested prior to dispatch. For end-of-life planning, we can advise on migration pathways to current Rexroth platforms (VT-HACD-1X, VT-MSPA2-1X) where direct replacement is no longer feasible.

Quality Control for the VT-VSPD Range

The VT-VSPD series presents specific quality control requirements due to its mixed analog/digital architecture and sensitivity to backplane power supply integrity. DriveKNMS applies the following test protocol to all VT-VSPD units:

Power supply verification: 24 VDC logic supply and ±15 VDC analog supply rails are measured under load before card insertion. Output stage functional test: each valve driver output is loaded with a calibrated resistive dummy load and driven through the full ±100% command range while monitoring current linearity and hysteresis. Serial communication test: RS-232 interface is verified for parameter read/write integrity using Rexroth WinPISA software. Enable logic test: digital enable input response time and fault relay output function are verified against specification. Thermal cycling: cards are subjected to a 0°C to 55°C thermal cycle to identify latent solder joint failures common in aged units. EEPROM integrity: stored parameter sets are read back and verified against factory defaults or customer-supplied backup files.

Units that do not pass all stages are quarantined and not offered for sale.