R902445797 A4VSO250EO2/30R-VPB25N00-SO368 Axial variable piston pump from Rexroth, Germany

FAQ:

Q1: What is the function of the "EO2" control? How does it differ from DRG?

A:​ The EO2​ is an Electro-Proportional Control​ that allows for remote electronic adjustment of the pump's displacement. Unlike the mechanically or hydraulically controlled DR/DRG variants, the EO2 uses an external electrical signal (typically 0–10 V or 4–20 mA) to proportionally control the swashplate angle and thus the flow output. This makes it ideal for automated systems requiring precise speed control or integration with PLCs.

Q2: What does the "VPB25N00" suffix and "SO368" special code indicate?

A:​ This code defines the mechanical configuration and a special order option:

• V: FKM (Viton)​ seals, offering superior chemical and high-temperature resistance.

• P: Standard parallel key shaft​ (DIN 6885).

• B25: Port size code 25​ (SAE flange ports with metric threads, larger than the common B13).

• N00: No through-drive​ (solid shaft end).

• SO368: Special Option Code 368. This is a factory-specific configuration (e.g., specific sensor, paint, or documentation package) that does not change the core hydraulic performance.

Q3: What is the key application difference between this EO2 pump and the previous DRG models?

A:​ The primary difference is the control method and system integration:

• EO2 (This model): Used in automated, closed-loop control systems. It requires an external electronic controller but offers precise, programmable flow matching and energy savings in complex machinery.

• DRG (Previous models): Used in hydraulically controlled systems. It is adjusted by a pilot pressure signal and is simpler but less precise for electronic integration.

  Both are A4VSO250 heavy-duty pumps but serve different automation levels.

Q4: What are the electrical requirements for the EO2 control?

A:​ The EO2 control typically requires:

• Power Supply: 24 V DC for the proportional solenoid.

• Control Signal: A analog input (e.g., 0–10 V, ±10 V, or 4–20 mA) to command the desired displacement.

• Controller: It is highly recommended to use it with a compatible Rexroth amplifier card (e.g., VT-5000 series) or a PLC with a proportional output module for stable control.

Q5: Can this pump be used in a closed-loop hydrostatic system?

A:​ No.​ The A4VSO EO2 is designed exclusively for open-circuit applications​ (pump → valve → actuator → tank). For closed-loop hydrostatic transmissions (e.g., travel drives), you would need an A4VG or A2FM series unit.