This depends on the actual design. Modern systems are linked. The damper is normally closed and opens through the fire alarm: the alarm starts the smoke exhaust fan and opens the smoke valve automatically.
The 280°C fire damper stays normally open. It is also called a high-temperature fire damper. It sits in ventilation ducts with high temperatures. At 280°C the fusible alloy melts and the damper closes. It can also be driven by a 24 V signal. The 280°C smoke fire damper stays normally closed. It sits in the smoke extraction duct. On a fire, the control centre sends a signal to open it and start extraction. At 280°C the fusible alloy melts and it closes. It is a two-action damper.
The smoke fire damper is a fire component. It fits on the duct of a mechanical smoke extraction system. It stays closed in normal use. On a fire it opens for extraction. When the smoke temperature in the duct reaches 280°C it closes, and within a set time it meets the leakage and fire-resistance integrity requirements, blocking smoke and fire. Main materials: carbon steel, galvanised sheet and stainless steel.
The 280°C fire damper stays normally open, also called a high-temperature fire damper. It fits ventilation ducts with high temperatures. At 280°C the fusible alloy melts and the damper closes. It can be driven by a 24 V signal. The 280°C smoke fire damper stays normally closed; on a fire the control centre signals it open for extraction, and at 280°C the fusible alloy melts and it closes. It is a two-action damper.