Product Description:

The VT-VRPD-2-26/V0/0-0-1 is an electric amplifier card produced by Bosch Rexroth Indramat for the VT-VRPA Electric Amplifiers series. Designed for proportional hydraulics, the board receives low-level command signals, shapes them, and delivers controlled current to the solenoids of 4WRE 6 and 4WRE 10 directional valves. It serves as an interface between a PLC or analog motion controller and the hydraulic actuator, providing ramp generation, reference scaling, and feedback processing so that cylinders and motors follow velocity or position commands in automated presses, test rigs, and material-handling machines.

The analog input stage is configured for differential signaling, which minimizes noise when cables run next to high-current power lines. Internal reference rails supply a positive limit of +10 V and a negative limit of -10 V, providing a symmetrical ±10 V control range that matches common motion controllers. Adjustable ramp generators modify the input so that spool movement starts in 0.01 s at the fastest setting or extends to 300 s for delicate positioning tasks. The amplifier can drive either 4/2 or 4/3 valve sections through shielded twisted-pair bus cable. It delivers current over solenoid leads up to 50 m long that use 2 × 1.5 mm² conductors, while a separate 50 m line with 4 × 0.25 mm² conductors connects the position transducer.

Digital operation is supported by 16 selectable setpoints that can be toggled from a host controller for rapid recipe changes. When connected to a computer, parameters are exchanged through an RS-232 port operating at 57,600 baud, allowing tuning data to be stored and reloaded without removing the card from its rack. A fieldbus can be daisy-chained over shielded twisted-pair cable. End-of-line signal integrity is maintained with a 120 Ω termination resistor on the board. The communication connections allow the amplifier to operate in distributed panels while receiving commands and feedback from the control system.