Product Description:

The VT-VSPA1K-1-1X-SO43A-1668 is a proportional amplifier card produced by Bosch Rexroth Indramat for the VT-VSPA Proportional Amplifiers series. Installed in a standardized Euro-Card rack, the module drives hydraulic proportional solenoid valves by translating a voltage reference into a controlled current output. In industrial automation, it sits between the machine control system and the valve, shaping electrical commands so that fluid power actuators receive accurate, repeatable force or position signals.

The card follows the Euro-Card outline with a length of 160 mm and a width of 100 mm, allowing quick insertion or removal during service. Command input sensitivity is set so that 6 V = 100% valve stroke, while the feedback loop is calibrated at 1 mV = 1 mA for straightforward current monitoring. Nominal supply is 24 VDC. Protection circuits permit operation down to 22 VDC and disconnect the output above 35 VDC to protect the solenoid windings. A 16-pole terminal strip handles all field wiring, and the internal reference source holds ±9 V within ±1% accuracy for analog setpoints. Reference circuitry draws only 25 mA, which helps limit loading on the upstream controller. Mechanical mass is limited to 0.1 kg, so vibration forces on the backplane remain low even in mobile or high-cycle machinery.

The amplifier’s dynamic stages can demand up to 1.8 A, and overall energy draw stays within 50 VA, which fits common control cabinet power budgets. A user-replaceable 2.5 A slow-blow fuse on the board shields traces and connectors from accidental shorts. The current input path presents 100 Ω resistance, which helps maintain predictable interaction with PLC and analog output sources. This arrangement supports stable valve control without placing excessive load on the incoming command signal.