What controls a smoke damper?
Smoke dampers close by an electric or pneumatic actuator, or a spring actuator, and can be either manually reset or driven open on a reset signal to the electric or pneumatic actuator.
What is the difference between fire damper and smoke damper?
Knowledge of these differences is imperative to the proper application of the dampers and their performance in the life/safety system. A fire damper closes once the duct temperature reaches a high enough level to melt a fusible link. A smoke damper closes upon the detection of smoke.
How do you size a damper?
A simple formula of Width X Height divided by 144 will give you the square footage of a damper. Example: The damper in question is 45 inches X 23 inches using the formula. 45 X 23 = 1035 divided by 144 = 7.1875 square feet of damper area.
Do smoke dampers need power?
Smoke dampers close by either an electronic or pneumatic actuator or a spring actuator. They can be reset manually or forced open on a reset signal to the actuator. Pneumatic actuators need air to function properly whilst electrical actuators need power to function successfully.
How does a smoke damper work?
Fire dampers respond to heat, when the temperature reaches a set point the damper slams shut. Smoke dampers respond to the detection of smoke, and close automatically. They can also be activated remotely. They resist the passage of smoke, toxic gases and air through a fire barrier.
Are fire dampers a legal requirement?
Under the Regulatory Reform (Fire Safety) Order it is a legal requirement to test fire dampers at regular intervals in accordance with fire safety in the design, management and use of buildings code of practice (BS:9999 2017), using a method known as ‘drop testing’.
Where do you put a fire smoke damper?
Fire dampers are installed in ducts passing through or in air outlet openings terminating at shaft walls, fire barriers (such as an occupancy separation wall, horizontal exit walls, corridor walls, corridor ceilings, floor-ceiling assemblies) and other fire resistance–rated assemblies as required by a building or life …
How do I choose a damper?
When beginning to size a damper, one needs to first calculate the kinetic energy at impact is generated by the load. This calculation depends upon a number of factors such as mass, impact speed, gravity, whether it’s free moving or driven, translational (linear) or rotational, and stroke of the shock.
Are smoke dampers normally open or closed?
Fire dampers, which rarely are actuated, close when a rise in temperature occurs and stay shut to stop fire from passing through a barrier. About 90 percent of fire dampers are curtain-type dampers that close when a mechanical fusible link melts, releasing a closing mechanism.
How do you reset a smoke damper?
The damper automatically resets if nuisance alarms occur and the system is reset. , the damper can be reopened by pressing the reset button located on the damper assembly. When temperatures in excess of 165°F/74°C (212°F/100°C or 285°F/ 141°C optional) are detected, the damper will close and lock.
How long do fire dampers last?
This gives guidance for the two main types of fire damper: spring operated fire dampers should be drop tested, cleaned and maintained at intervals of no greater than 12 months; while all other models should be drop tested, cleaned and maintained at least every two years.
How often should fire dampers be replaced?
one year
It states that all fire dampers should meet the criteria of fire resistance for a stated period of time and that: “All fire dampers should be tested by a competent person at regular intervals not exceeding one year, and to be repaired or replaced immediately if found to be faulty.
Do smoke dampers require retaining angles?
In wood framed openings, course thread drywall screws with a minimum of 1″ penetration into the framing are required. Smoke only rated damper do not require the retaining angles to be attached to the smoke barrier but the retaining angles are to be attached to the damper sleeve as described above.
How do you calculate damper torque?
Torque Formula:
- Damper Area (Ft2) =
- Torque Factor ( )
- Required Torque (LbIn) = Damper Area (Ft2) * Torque Factor * Torque Factor ( )
Where should smoke dampers be installed?
Smoke dampers must be installed at or adjacent to the point where the duct passes through the smoke barrier in accordance with NFPA 90A. The maximum installation distance is 24″ (610 mm) from the smoke barrier, however, the preferred location of leakage rated smoke dampers is in the smoke barrier.
Do fire dampers need servicing?
Why choose Johnson Controls damper controls?
At Johnson Controls, we offer Damper Controls in a diverse range of models. Choose from both rectangle and round configurations designed specifically for things like safety applications, low-leakage and heavy duty industrial needs, and backdraft for pressure relief.
What is a smoke damper actuator?
The Low Torque Electric Smoke Damper Actuator is a spring return Direct Coupled Actuator (DCA) with an integral junction box for on/off signal from a Single Pole, Single Throw (SPST) controller. Models are designed to operate reliably in smoke control systems
What is low torque electric smoke damper control?
for modulating damper control designed to operate reliably in smoke control systems requiring Underwriters Laboratories Inc.® (UL) 555S ratings up to 250°F. The actuator accepts a 0 to 10 V or 4 to 20 mA signal from a controller. The Low Torque Electric Smoke Damper Actuator is a spring return Direct Coupled Actuator (DCA) with an
Are Johnson Controls fire dampers ul 555 rated?
Johnson Controls’ Multi-blade Fire dampers are UL Standard 555 rated for 1.5 hours. These dampers meet the requirements of the 1996 edition of NFPA-90A for use in a fire partition rated less than three hours. They are dynamically rated for up to 3500 fpm air flow and 8 inches static pressure.