VT-VRPA1-527-10/V0/PV-RTP

The VT-VRPA1-527-10/V0/PV-RTP is an electric amplifier card produced by Bosch Rexroth Indramat for the VT-VRPA Electric Amplifiers series. The module conditions command and feedback signals so that a proportional pressure valve receives precise coil current. Installed in a 19-inch rack, it generates adjustable reference voltages and drives the solenoid of a DREB6X pilot valve. This arrangement supports hydraulic pressure regulation in automated presses, test stands, and other closed-loop motion systems.

The board measures 100 mm in depth and occupies a front width of 7 TE, allowing it to fit standard Eurocard slots while leaving space for adjacent modules. A 24 VDC supply powers the amplifier, which draws a peak current of 1.5 A. The card converts this input into control power limited to 35 W, helping control heat generation within the cabinet. Command signals enter through a source impedance of 1 kΩ, while the internally generated +10 V reference supports external potentiometers that can draw up to 10 mA for setpoint adjustment. All field and power lines terminate on a DIN 41612-F32 connector, allowing the card to be disconnected without disturbing individual wiring connections. The signal-processing circuitry regulates solenoid current so that hydraulic output follows the electrical command curve with consistent accuracy.

Closed-loop operation uses a carrier frequency of 7.8 kHz to support responsive pulse-width modulation of the output current. The valve feedback winding produces 10.2 V RMS, providing the amplifier with an error signal for comparison with the command input. The control circuit continuously evaluates this difference and adjusts the output stage to maintain the requested pressure response. To magnetize the solenoid, the output stage supplies 2.7 A at up to 25 W, providing sufficient drive for operation across the valve’s pressure range. Adjustable reference signals allow the hydraulic response to be tuned for the connected control system without placing an excessive electrical load on external command devices.