VT 1600-3X-1 by Bosch Rexroth Indramat

The VT 1600-3X-1 is a plug-in servo amplifier card produced by Bosch Rexroth Indramat for closed-loop control of proportional valves in hydraulic automation. Belonging to the VT 1600 Servo Amplifiers series, the card conditions analog command signals and modulates coil current so that spool position follows electrical demand. Placing the amplifier directly inside a 19-inch rack reduces discrete wiring and supports repeatable valve dynamics within machine tools, presses, and material-handling lines.

The board follows the Eurocard format and measures 100 × 160 mm, allowing direct insertion into standard DIN 41494 subracks. Its output stage is matched to proportional solenoids with a coil resistance of 2000 ?, ensuring stable current regulation without overheating. A differential command path accepts a reference of ±10 VDC, covering the full valve stroke from negative to positive flow. Internal power rails use a dual supply of ±24 VDC, so the module can be powered from common industrial control supplies. To reduce spool hysteresis, the amplifier injects a 3 mApp dither signal at 340 Hz, which keeps the valve moving through static friction and promotes a smooth response at low flow rates. The front plate is 128 mm high and 8 HP wide, supporting installation in densely arranged control cabinets.

The control loop has a maximum current draw of 200 mA, keeping power dissipation low in multichannel racks. A protected auxiliary rail delivers ±15 VDC for external sensors or potentiometers that share the same ground reference. Field wiring terminates at a 32-pin plug mounted on the board edge, simplifying card removal during service. With a mass of only 0.15 kg, the lightweight card places minimal load on the backplane guides. The solder-side conductors have a width of 5.08 mm, while the relay has a duty cycle of 1 ms to support fast valve actuation without overheating the circuit traces.