This document describes the analog amplifier modules VT-MRPA2 and VT-MRPA1 produced by Bosch Rexroth AG. These modules are designed for controlling 4WRE type directional valves with electrical position feedback. They feature adjustable ramp time and characteristic curve correction, as well as features such as selector inputs, power supply reverse polarity protection, and cable disconnection detection in the displacement sensor branch.
The VT-MRPA2 and VT-MRPA1 are modular analog amplifier modules designed for 4‑way proportional directional control valves (4WRE). They operate from a 24 VDC supply and feature differential input control, slope‑function generation, and built‑in fault detection. The modules mount on EN 60715 hat‑type rails and include a power unit with current limiting.
Key functions include adjustable ramp times, symmetric step‑size adjustment (VT‑MRPA2), limiter, oscillator for displacement sensor signals, and a current output stage limited to 2.5 A with short‑circuit protection. Safety notes cover power‑off wiring, cable shielding, and recommended cable types.
| Working voltage | 24 VDC ±40% / –20% |
|---|---|
| Power consumption | < 24 VA |
| Current consumption | < 2 A |
| Output current | 0 – 2.5 A (short‑circuit protected) |
| Protection | Fuse and thermal overload protection |
| Dimensions (W×H×D) | 40 × 79 × 85.5 mm |
| Ingress protection | IP20 |
| Operating temperature range | -0 °C to +50 °C |
Both modules require a 24 VDC supply with a tolerance of +40 % / –20 %.
Each module provides 12 screw‑type terminal connections for wiring.
The amplifier module must be disconnected from its power source before any wiring is performed.