Frequently Asked Questions (FAQ)

Q1: What is the function of the "DR" control?

A:​ The DR​ is a Pressure Compensator. It automatically reduces the pump's displacement (destrokes) when the system pressure reaches the preset value. This maintains constant pressure while minimizing energy consumption and heat generation.

Q2: What does the "VPA42N00" suffix indicate?

A:​ This code defines the mechanical configuration:

• V: FKM (Viton)​ seals for high temperature and chemical resistance.

• P: Tapered shaft​ (1:5) with a parallel key.

• A42: Port size code 42​ (SAE flange ports with UNC threads).

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

Q3: What is the key difference between this A10VSO71 and the previously mentioned A10VSO45?

A:​ The primary difference is the displacement size:

• A10VSO71: 71 cm³/rev, providing higher flow output (~156 L/min vs ~117 L/min at same speed).

• A10VSO45: 45 cm³/rev, smaller size for lower flow requirements.

  This model uses a simpler DR​ pressure control, whereas the previous ones used DFR1​ (pressure + load sensing).

Q4: What is the purpose of the L port?

A:​ The L Port (Case Drain)​ must be connected directly to the tank. It relieves internal leakage pressure to protect the shaft seal. Maximum allowable backpressure is typically 2 bar.

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

A:​ No.​ The A10VSO DR is designed exclusively for open-circuit applications​ (pump → valve → actuator → tank). For closed-loop hydrostatic transmissions, you would need an A4VG or A2FM series unit.