Product Description:

The VT 2000 S 48 proportional amplifier from Bosch Rexroth Indramat belongs to the VT 2000 Proportional Amplifiers series. It is designed to drive a single proportional solenoid in hydraulic valves and to translate a control signal from a PLC into accurate coil current. By controlling the magnet force, the unit meters oil flow or pressure in closed-loop motion axes used on presses, molding machines, and test stands. The board format permits direct mounting in a Eurocard rack within a machine control cabinet.

It operates from a nominal supply of 24 VDC, but the design tolerates supply excursions down to 22 V and up to 35 V without losing regulation. Internal consumption stays below 1 A, and overall power draw is limited to less than 25 VA, which simplifies cabinet heat calculations. The amplifier can bias the coil with up to 300 mA for valve centering and will deliver a peak solenoid current of 800 mA under full command. A differential reference stage produces a regulated ±9 V rail that supplies the signal-conditioning circuits, helping the board maintain linearity when ambient temperature fluctuates. With a measured coil resistance of 19.5 Ω, the specified current bandwidth aligns with typical two-stage proportional valves.

For external control, the card provides a voltage command interface, and a full-scale drive signal of 6 V corresponds to the maximum coil current. Feedback is returned through a measurement shunt that follows the scale of 1 mV = 1 mA, enabling simple monitoring with standard analog inputs. To protect upstream wiring, the front panel incorporates a slow-blow fuse rated at 2.5 A T, which isolates the supply if a short occurs in the solenoid circuit. The command input and current-monitor output allow the control system to compare the requested signal with the actual solenoid current during operation.