Product Description:

The VT-VRPA1-52-10a/V0/0 is an electric amplifier card manufactured by Bosch Rexroth Indramat for the VT-VRPA Electric Amplifiers series. The card uses a 100 × 160 mm Eurocard format and connects through a 32-pin DIN 41612 Form D connector. It conditions command signals and supplies controlled current to proportional solenoids in hydraulic valves, allowing PLCs or motion controllers to regulate fluid power with electronic precision.

This card operates from a nominal supply of 24 V DC, and its internal circuitry remains active down to the 22 V minimum. A bias current of 550 mA establishes the quiescent operating point so the valve spool centers predictably before modulation begins. The differential input resistance of 100 Ω presents a consistent load to upstream analog sources, minimizing signal distortion. The onboard oscillator runs at 2.5 kHz ±10%, generating a high-frequency carrier that the power stage converts into a pulse-width-modulated drive signal. A superimposed dither signal of 300 Hz ±10% reduces friction in the hydraulic spool and improves repeatability at low stroke levels. Internally regulated rails are maintained at ±9 V ±1% to supply the analog sections. A 1 kΩ measuring socket permits nonintrusive current measurements during setup.

The protection path uses a 2.5 A T fuse, which isolates the module if an external fault causes current consumption to exceed safe limits. The protection circuit also responds if external loads draw more than the permitted ±25 mA. The output stage can deliver a controlled solenoid current of up to 1.2 A ±10% into coils with a resistance of 12.7 Ω, matching typical proportional valve requirements. When the host machine’s supply rail experiences transient overvoltage, the card tolerates excursions up to 35 V without component breakdown. Its total mass is 0.15 kg, which keeps rack loading low. The Eurocard outline fits standard backplanes and supports installation in compatible amplifier racks.