Product Description:

The VT 3000 36 is an analog amplifier card manufactured by Bosch Rexroth Indramat in the VT 3000 Analog Amplifiers series. It is designed for proportional valve control within industrial automation systems. The card conditions differential command signals and supplies regulated current to hydraulic solenoids to achieve stable flow or pressure regulation. This type of card is used where electrical control signals must be translated into a smooth hydraulic response.

The amplifier runs from a nominal supply of 24 VDC, and this voltage is applied to internal regulators that derive a stable reference for the command-stage op-amps. Incoming command lines are accepted through differential inputs with a resistance of 100 kΩ, a value that minimizes loading on upstream controllers. A differential input stage also helps reduce the effect of electrical noise on long control runs. The PWM generator operates at a carrier of 170 Hz, setting the update rate for the solenoid current loop. Pulse-width modulation allows the card to regulate average coil current smoothly rather than drive the load as a simple on or off output. At the output stage, the card can deliver up to 800 mA to a single proportional solenoid, and the identical value is mirrored at the diagnostic jack where full-scale drive produces 800 mV for oscilloscope monitoring. These values set the operating range of the output stage and provide a way to check loop integrity without interrupting the circuit.

Supporting circuitry is powered by an auxiliary rail of ±9 V that can supply up to 25 mA for external potentiometers or sensors. This makes it possible to feed low-power setpoint devices directly from the card. Primary input protection is provided by a 2.5 A T fuse, which disconnects the card when supply faults exceed the rated current. Reliable operation is maintained up to a maximum ambient of 50 °C, so cabinet ventilation must keep temperatures below this limit during continuous duty. All signals pass through a 32-pin DIN 41612 Form D connector, making the Euro-Card format of 100 × 160 mm compatible with standard rack assemblies. The connector arrangement also supports installation in standard backplanes used for modular control hardware.