VT-VRPA1-527-10/V0/PV

The VT-VRPA1-527-10/V0/PV is an electric amplifier card produced by Bosch Rexroth Indramat for the VT-VRPA Electric Amplifiers series. It interfaces with proportional pressure valves to convert low-level control signals into regulated drive current, allowing closed-loop pressure control in automated hydraulic systems. Designed as a plug-in module, the card mounts directly in standardized industrial racks and supplies the regulated coil current required by DREB6X valves used on machinery and test stands.

The module operates from a regulated 24 V DC supply and has a maximum power draw of 35 W, which helps determine cabinet heat dissipation requirements. The output stage can deliver a peak solenoid current of 2.7 A, providing controlled magnetizing force to connected field devices. Physical integration is simplified by the DIN 41612 F32 male connector, which aligns with backplane wiring on a standard Eurocard frame. An internal current limit of 1.5 A on the auxiliary rails prevents shared power supplies from being overloaded. The potentiometer supply channel provides 10 mA, allowing external potentiometers to set command values without stressing their thin-film tracks.

Closed-loop feedback uses a reference excitation of 10.2 V RMS at 7.8 kHz. This frequency avoids overlap with typical PLC scan rates and reduces noise coupling. The onboard reference rail supplies +10 V, allowing sensors or manual set-point controls to generate the required control voltages. The input circuit is tuned for a 1 kΩ signal source to maintain accurate scaling. During sustained actuation, the coil can absorb up to 25 W, which supports thermal calculations for the hydraulic manifold. The separate reference and input paths support stable transfer of command and feedback signals before the output stage regulates valve current.