Axial Piston Variable Pump A7VO - Group VH A/S

Blocked for new applications / Für Neuanwendung gesperrtRE 92 202/03.06 A7VO Bosch Rexroth AG 15/32EP Electrical Control with Proportional SolenoidWith the electrical control with proportional solenoid, the pumpdisplacement is adjusted proportionally to the solenoid current,resulting in a magnetic control force, acting directly onto thecontrol spool that pilots the pump control piston.Control from V g min to V g maxWith increasing control current the pump swivels to a higherdisplacement.A control pressure of 40 bar is required to swivel the pumpfrom its starting position V g min to V g max .The required control pressure is taken either from the operatingpressure, or from the externally applied control pressure at theY 3 port.To ensure the control even at low operating pressure < 40 barthe port Y 3 must be supplied with a external control pressure ofapprox. 40 bar.Note:– Install pump with EP control in the fluid tank only when usingmineral hydraulic fluids and an fluid temperature in the tankof max. 80° C.To control the proportional solenoids the following electronicamplifi er and controller are available (also as to the Internetunder www.boschrexroth.com/mobile-electronic):– BODAS controller RC (RE 95200)and application software– Analog amplifier RA (RE 95230)By using an proportional amplifier control of swivel time is alsopossible.Characteristic EPControl current I in mA800700600500400300200100Circuit diagram EPUR0 0,2 0,4 0,6 0,8 1,0V g min Displacement V g maxV g maxV g minY3B (A)A1X3STechnical data of solenoidsEPVoltage 24 VDC (±20%)Control currentStart of control at V g min200 mAEnd of control at V g max600 mALimiting current0,68 ANominal resistance (at 20°C)19,5 ΩDither frequency100 HzDuty cycle 100%Type of protection (HIRSCHMANN)IP65to DIN EN 60529EP.Gsee HD.GElectrical control, for pressure cut-off,remote controlledNoteThe spring centering in the pilot control unit is not asafety deviceThrough contamination in the control unit – e.g. in hydraulicfluid, wear particles, or particles out of a system – the valvespool can get stuck in an undefined position. In this case, thepump flow does not follow the command inputs of the machineoperator anymore.– Make sure that a proper emergency shut down functioncan bring the driven machine movements to a safe positionimmediately (e.g. stop).– Adhere to the specified cleanliness level 20/18/15 (90 °C) to ISO 4406.