For overhead and gantry cranes, normally closed brakes are most common on safety-critical mechanisms, especially hoisting. “Normally closed” means the brake is applied when power is off, which aligns with fail-safe behavior: if power fails, the brake engages automatically to hold the load. These are typically spring-applied, power-released designs (electro-hydraulic, hydraulic, pneumatic, or electromagnetic release).
Normally open brakes—released when unpowered and requiring power to apply—are less common in crane safety functions because a power loss could result in loss of braking. They may appear in specialized process equipment where unintended stopping is undesirable, but they require careful risk assessment.
In practice, when people say “normally closed crane brake,” they usually mean “fail-safe hoist brake.” Always verify the mechanical principle (spring-applied) rather than relying on the label. For crane owners, normally closed fail-safe braking is the standard expectation for safe holding and emergency response.