What characteristic differentiates a compound (pilot operated) relief valve from a direct acting relief valve?

A compound (pilot operated) relief valve is designed to operate efficiently in specific applications where pressure control is essential. One key characteristic that differentiates it from a direct acting relief valve is its ability to achieve lower pressure overrides. This means that it can maintain a more stable pressure setting with less fluctuation, which is essential in systems that require precise control.

In a pilot operated relief valve, the pilot mechanism allows it to open and close at lower pressure levels compared to direct acting relief valves. This enables the compound valve to provide better modulation and response in controlling system pressure, as the pilot valve can react quickly to changes in the system, thus ensuring that the main valve can operate at more uniform pressure conditions.

Understanding this distinction helps in selecting the appropriate type of relief valve for various applications, especially where maintaining a consistent operating pressure is critical.