Why do some people say that the electric smoke exhaust fire damper is normally closed and some people say that it is normally open?

Electric smoke exhaust fire damper generally has two ways: normally open and normally closed:

1, normally open smoke exhaust fire damper, with the following functions:

(1) normally open, and keep the valve open in case of fire.

(2) When the pipeline temperature reaches 280℃, the fuse will act and the valve will automatically close.

(3) Output the valve closing signal and interlock the smoke exhaust fan to stop.

(4) Manual closing and manual opening.

2. Normally closed smoke exhaust fire damper has the following functions:

(1) is normally closed. In case of fire, the control center inputs DC24V power and the valve opens quickly.

(2) Output the valve opening signal and interlock the fire smoke exhaust fan.

(3) Open it manually. Manual reset shutdown.

(4) When the temperature of the pipeline reaches 280℃, the fuse acts and the valve closes again.

Extended data

Use of smoke exhaust fire damper

1, normally in the open state, closed when the smoke temperature in the smoke exhaust pipe reaches 280 degrees in case of fire, which meets the requirements of smoke leakage and fire resistance integrity in a certain period of time, thus playing the role of smoke isolation and fire resistance.

2. The valve can be closed by DC24V power supply (electric smoke exhaust fire damper).

3. Manual shutdown or manual reset.

4. Electric reset after 4.DC24V is turned off (fully automatic smoke exhaust fire damper, suitable for places inconvenient for manual operation).

5. Output valve closing signal, which can be interlocked with other fire prevention equipment.

Advantages of smoke exhaust fire damper

1, low air leakage and good air tightness;

2, the electric starting current consumption is small;

3. Strong corrosion resistance and long service life (made of stainless steel);

4. The actuator is driven flexibly, and the feedback and interlocking signals are accurate.

References:

Baidu encyclopedia-smoke exhaust fire damper