What does the term "fail active" refer to in hydraulic systems?

The term "fail active" in hydraulic systems refers to a condition where a system component, such as a valve, maintains its operational status or opens when power is lost or when the system experiences a failure. This is designed to ensure that critical functions continue to operate even in the event of a failure, thus providing a level of safety and reliability.

In the context of hydraulic systems, a valve that "fails active" can allow fluid to continue flowing, which is crucial in applications where maintaining pressure or allowing for fluid movement is necessary to prevent hazardous situations. By contrasting this with fail-safe conditions where systems automatically revert to an inactive state or safely shut down, the concept of "fail active" highlights the importance of maintaining operational capacity during power loss or system failure scenarios.

This characteristic is especially important in applications where system integrity or hazard prevention is key, as it defines how the system behaves under abnormal conditions and potentially safeguards against catastrophic failures.