Product Description:

The VT 2000 K 43-2 proportional amplifier card is produced by Bosch Rexroth Indramat for the VT 2000 Proportional Amplifiers series. Intended for rack installation in electro-hydraulic motion systems, the board converts low-level command voltages into controlled solenoid current so that a valve spool follows a commanded reference. Hot-swap capability and standardized connectors allow the board to be replaced or recalibrated without disturbing field wiring. It is used where proportional valves must respond smoothly to electrical command changes during hydraulic motion control.

During operation, the board uses a nominal 24 VDC supply, yet it remains functional between the 22 V lower and 35 V upper limits common on mobile or machine power nets. A time-rated blade fuse of 2.5 A T protects the rack against unintended shorts. Internally, the amplifier regulates the rail down to ±9 V, stabilizing the analog stages that process a +6 V command input and an 800 mV feedback input. The primary reference channel accepts a full-scale input of +9 V, while a second input can reach +10 V for dual-loop control. With a minimum ramp of 30 ms, the card smooths step changes and helps reduce hydraulic shock. The driver can still deliver up to 800 mA to a 19.5 Ω solenoid when full stroke is required, while bias current is limited to 300 mA to maintain a stable null position.

The compact 100 × 160 mm Eurocard slides into a carrier that mates with a 32-pin DIN 41612 Form D backplane. Its input 2 impedance of 100 kΩ remains fixed without soldering, which helps minimize loading on upstream PLC cards and other analog signal sources. The differential stages maintain controlled current output for the connected valve. The ramp generator coordinates bias and solenoid limits so voltage references are translated into predictable valve movement across repeated operating cycles.