3C fire dampers are generally installed on the air ducts of smoke exhaust systems, used for smoke exhaust in the event of a fire, and automatically close when the temperature inside the air ducts reaches 280 ℃. Adopting SFD control device, power supply DC24V, 0.5A. Normally closed, it opens when receiving a DC24V electrical signal from the control center. Manually open, manually reset. Output an open signal after the valve is activated.