VT-SR7-1X/0/A4VS.355HS

The VT-SR7-1X/0/A4VS.355HS is an electronic plug-in card produced by Bosch Rexroth Indramat for the VT-SWMA Modules series. Intended for installation in standardized 19-inch racks, the card conditions command signals and actuates servo-hydraulic valves in automated machinery. By combining internal dither generation and relay switching on a single board, the module supplies the precise current loop required for directional or pressure control valves while returning position data to the supervisory drive. Its integrated functions simplify cabinet wiring and help maintain repeatable motion profiles across production cycles.

The control electronics are powered by an auxiliary supply of ±15 V DC, while a separate operating bus of ±24 V DC drives the push-pull output transistors and onboard relay. The board follows the Eurocard format and occupies 1 TE, or 5.08 mm, of front-panel width, allowing dense installation in multi-axis systems. All field and rack connections are routed through a 32-pin DIN 41612 Form D connector, so the card can be removed without disturbing the fixed wiring. A factory-set dither oscillator operates at 340 Hz, helping reduce valve stiction and improve control resolution at low flow rates.

The power section uses a push-pull bipolar driver that delivers up to ±60 mA of valve current, matching the requirements of typical Bosch Rexroth pilot stages. Position information returns through an inductive feedback interface, enabling closed-loop centering without external signal scaling. A plug-in relay is energized at the +24 V call-up level and has a nominal coil voltage of +26 V. Its winding has a resistance of 700 Ω, which limits current demand on the control supply. The relay inserts or removes the drive path in response to the call-up signal. Because the module does not include an onboard voltage regulator, stable operating power must be provided by upstream cabinet supplies.