Product Description:

The VT 2000 S 40 is a plug-in proportional amplifier card produced by Bosch Rexroth Indramat for the VT 2000 Proportional Amplifiers series. Installed in valve control racks, the card conditions a 24 VDC supply and delivers regulated current to proportional solenoid actuators, enabling closed-loop positioning and force control in hydraulic automation circuits. It is intended for rack-based hydraulic control systems that require stable electrical actuation from compact plug-in electronics.

Physically, the board follows a 100 x 160 mm Eurocard format and inserts through a 32-pin DIN 41612 Form D connector at the rear of the rack. Normal operation uses a 24 VDC supply, and the design tolerates input dips to 22 V to accommodate line variation. Input command signals pass through a differential stage with an input resistance of 100 kΩ, which limits loading on upstream controllers. Internally, the amplifier draws no more than 1 A, and its total dissipation remains below 25 VA maximum, which helps with power-supply sizing in racks that hold multiple cards. On the output side, the pulse-width-modulated driver supports continuous solenoid current up to 800 mA, while bias can be trimmed to 300 mA so the valve remains centered when idle.

Protection and service parameters are handled at the front panel, which is 128.4 mm high and carries a replaceable 2.5 A T fuse that opens if current draw exceeds fault limits. The regulated current monitor delivers ±25 mA for external meters, and an auxiliary reference of ±9 V is available for sensor excitation. Overvoltage margins are limited by a design ceiling of 35 V, while undervoltage detection helps maintain stable operation. The solenoid channel is matched to coils of 19.5 Ω, and overall board mass is only 0.1 kg, allowing dense stacking without additional mechanical support. Clearly labeled trimmers allow straightforward adjustment in closed-loop hydraulic assemblies.