Product Description:

The VT-VRPA1-527-10/V0 is a plug-in electric amplifier card manufactured by Bosch Rexroth Indramat for the VT-VRPA Electric Amplifiers series. Designed for proportional directional or pressure control tasks, the module converts low-level command voltages into controlled current for NG 6 pilot valves in hydraulic automation. By placing the card in a standardized backplane, system builders can integrate closed-loop control of spool position or pressure without additional discrete electronics.

The amplifier operates from a 24 V DC nominal supply and draws a continuous board current of 1.5 A, so cabinet fusing can be sized accordingly. Under typical conditions, it dissipates 37 W, and the onboard heat sink is sized for that thermal load. Input and output wiring is collected on a DIN 41612-F32 connector, allowing quick replacement without rewiring. A bulk storage network containing a 4700 µF / 63 V DC electrolytic capacitor smooths the supply to limit ripple during rapid spool movements. For external command devices, the card sources 10 mA to a 10 kΩ signal potentiometer, and the internal pot supply is protected by a 100 mA fault output that signals an overcurrent event to the host controller.

The output stage supports a maximum solenoid current of 2.7 A and a maximum solenoid power of 40 VA, allowing the driver to energize high-flow NG 6 pilot valves without saturating the power stage. The analog setpoint channel presents 100 kΩ of input resistance, minimizing burden on remote PLC outputs, while the pilot feedback path is terminated with 20 kΩ to help maintain linear sensor scaling. Additional functions include a 10 mA reference feed for external potentiometers, and the card accepts NG 6 valve connectors. This layout lets the module serve as a compact interface between low-level electronics and proportional hydraulic components.