Product Description:

The VT 2000-K-44/2 is a plug-in proportional amplifier card supplied by Bosch Rexroth Indramat within the VT 2000 Proportional Amplifiers series. Mounted in a 100 × 160 mm Eurocard frame, it slides into standard control racks and connects to directional or pressure valves through a 32-pin male connector. In an automation loop, the module converts ±10 V or 4–20 mA command signals into regulated solenoid current so hydraulic actuators follow electronic references with repeatable metering characteristics.

The power section operates from an input of 24 V DC, and protection circuits allow continued operation down to 22 V while cutting off the output above 35 V to prevent coil overheating. Output to the valve windings is limited to 800 mA, a ceiling that matches solenoids with a cold resistance of 19.5 Ω and keeps magnetic force linear. The differential input presents an impedance of 100 kΩ, so upstream controllers experience negligible load even on long signal runs. Internally, the board draws no more than 1 A, and its 2.5 A time-delay fuse interrupts abnormal surges. A stabilized ±9 V reference supplies the onboard electronics, while the adjustable bias circuit provides offset correction.

Dynamic response is shaped by a minimum ramp time of 30 ms, allowing pressure or flow changes to occur without inducing hydraulic shock. During steady operation, the board’s power draw stays below 25 VA, an important consideration when several channels share a cabinet supply. The adjustable bias channel can add up to 300 mA to the command-related output so valves with preload springs reach the null position before modulation begins. Continuous service is permitted within an operating temperature range of 0 to 50 °C. Convection cooling within the rack is normally sufficient throughout this temperature range, provided that airflow around the card is not obstructed.