The difference of A4VG90EP, EP0, EZ, HD, Hand control valves

When discussing the A4VG90 series and its variants like the A4VG90EP, EP0, EZ, HD, and models with hand control, it’s important to understand that each designation indicates a specific set of features or modifications tailored to meet different operational requirements or applications.


  • EP typically stands for “Electric Proportional” control. This variant is designed to offer precise control over hydraulic flow and pressure through electric signals. The valve adjusts the hydraulic functions proportionally based on the input from electronic control units (ECUs), allowing for smooth and precise operations. Ideal for applications requiring dynamic response to control inputs and fine adjustment capabilities.


  • EP0 might indicate a specific version or configuration within the electric proportional control lineup. This could involve particular control features, software, or hardware optimizations designed for specific applications or requirements. The exact differences would depend on the manufacturer’s specifications but generally, this designation suggests enhancements or specific adaptations to the basic EP model.


  • EZ could denote a variant equipped with special features or designed for specific environments or applications. Without direct reference to the manufacturer’s coding conventions, it’s challenging to specify what EZ stands for precisely. It might relate to a particular type of electronic control, environmental adaptation (such as extreme temperatures), or a specialized application (such as zero-leakage for precision hydraulics). The focus is usually on offering solutions to niche requirements.


  • HD is commonly used to represent “Heavy Duty.” Valves with this designation are built to withstand harsh conditions, higher pressures, and more rigorous use. They might feature more robust construction, enhanced materials, and design modifications that enable them to perform reliably in demanding applications such as construction machinery, mining equipment, and other high-stress environments.

Hand Control

  • Hand Control valves are manually operated, allowing the operator to control the hydraulic functions directly through levers or knobs. This type of control is distinct from the electrically or electronically controlled variants (like EP) and is suited for applications where manual override or direct physical control is preferred. Hand control valves are valued for their simplicity, reliability, and direct feedback to the operator.

Comparison summary

  • Control Type: The primary difference lies in the method of control—electric proportional (EP) versus manual (Hand Control). EP variants offer precise adjustments through electronic signals, while hand control models rely on physical input.
  • Application Focus: Each designation (EP, EP0, EZ, HD) hints at adaptations for specific operational needs—be it enhanced electronic control, application-specific features, environmental adaptations, or heavy-duty performance.
  • Durability and Precision: HD models emphasize durability for tough environments, whereas EP models prioritize precision and dynamic control. The specific adaptations in EP0 and EZ models would cater to nuanced requirements within these broad categories.

The A4VG90 series encompasses a range of valve designs to cater to diverse hydraulic system requirements, from precise electronic control to robust performance in harsh conditions and straightforward manual operation. The specific model designation helps users identify the right valve for their application based on control type, environmental adaptation, duty level, and specific performance features.