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Fire & Smoke Actuator, 30 in-lb [3.5 Nm] from 32...350°F [0...177°C], Spring return, AC/DC 24 V, On/Off, 2 x SPST

46 in stock

Fail-safe position

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Weight 4.2 lbs
Auxiliary Switch




Actuator Type

Spring return

Control type


maintenance free
30 in-lb
Torque motor
30 in-lb [3.5 Nm] from 32...350°F [0...177°C]
Torque note
from 32...350°F [0...177°C]
Power consumption in operation
15 VA
Power consumption in rest position
2.5 W, 3.5 VA, End stop 25 VA, 1 A slow blow fuse *
Transformer sizing
24 VA (class 2 power source)
Ambient humidity
5...95% r.H. non-condensing
Housing material
zinc coated steel
Electrical Connection
18 GA, 3 ft [1 m], 2 color coded wires
Auxiliary switch
2 x SPST, 3A resistive (0.5A inductive) @ 250 VAC, one set at 10°, one set at 85°
Switching capacity auxiliary switch
3A resistive (0.5A inductive) @ 250 VAC
Auxiliary switch note
one set at 10°, one set at 85°
Angle of rotation
Position indication
visual indicator, 0° to 95° (0° is full spring return position)
Ambient temperature
32...122°F [0...50°C]
Non-operating temperature
-40...176°F [-40...80°C]
direction of rotation spring-return
reversible with cw/ccw mounting
Overload Protection
electronic throughout 0° to 95° rotation
Electrical Protection
actuators are double insulated
Quality Standard
ISO 9001
Degree of Protection
IP30, NEMA 1
direction of rotation motor
reversible with CW/CCW mounting
Data sheet type
CAD ThomasNetLink
Product Features
Fire & Smoke damper actuator
Nominal voltage
AC/DC 24 V
Nominal voltage AC
24 V
Nominal voltage DC
24 V
Nominal voltage frequency
50/60 Hz
Power Supply
24 VAC, ±10%, 50/60 Hz, 24 VDC, 0% / +50%
Power supply tolerance AC
Power supply tolerance DC
0% / +50%
Electrical accessories
Family Series
FSLF Series
Shaft Diameter
3/8" to 1/2" round, centers on 1/2"
Running time selection
2.5...19 sec
Running Time (Motor)
<15 sec at rated voltage and torque 32...122°F [0...50°C]
Running time motor note
at rated voltage and torque 32...122°F [0...50°C]
Running time (Fail-Safe)
15 seconds
Running Time (Fail-Safe)
<15 sec
Emergency control function
Spring Return
Noise Level (Fail-Safe)
45 dB (A) motor, 62 dB (A) spring, inaudible holding 
Degree of protection IEC/EN
Degree of protection NEMA/UL
Not purchasable function
Tagging function
Auxiliary Switch
The type FSLF spring-return actuator is intended for the operation of smoke and combination fire and smoke dampers in ventilation and air-conditioning systems. The actuator will meet requirements of UL555 and UL555S when tested as an assembly with the damper and will meet requirements of UBC for 15 second opening and closing. Square footage of damper operated will depend on make and model and the temperature required. IMPORTANT 24VDC NOTE: The FSLF24 & -S models will not operate below 24VDC. A filtered and regulated power supply must be used.
Mounting of the actuator to the damper axle shaft or jackshaft is via a cold-weld clamp. Teeth in the clamp and V-bolt dig into the metal of both solid and hollow shafts maintaining a perfect connection. The specially designed clamp will not crush hollow shafts. The bottom end of the actuator is held by an anti-rotation strap or by a stud provided by the damper manufacturer. The actuator is mounted in its fail safe position with the damper blade(s) closed. Upon applying power, the actuator drives the damper to the open position. The internal spring is tensioned at the same time. If the power supply is interrupted, the spring moves the damper back to its fail-safe position.
Typical Specification
All smoke and combination fire and smoke dampers shall be provided with Belimo FSTF, FSLF, FSNF, or FSAF actuators. All substitutions must be approved before submission of bid. Damper and actuator shall have UL 555S Listing for 250°F (350°F). Actuator shall have been tested to UL 2043 per requirements of IMC 602.2 and NEC 300.22 (c). Where position indication is required -S models with auxiliary switches or damper blade switches will be provided per code requirements.
Agency Listing
cULus acc. to UL60730-1A/-2-14, CAN/CSA E60730-1:02, Listed to UL 2043 - suitable for use in air plenums per Section 300.22(C) of the NEC and Section 602 of the IMC. NYC Department of Buildings MEA 197-07-M California State Fire Marshal Listing 3210-1593:102
Safety Notes
* Neither UL nor Belimo require individual fusing of FSLF actuators. The FSLF draws higher peak current when driving against its end stop or any other type of stop. Given the technology of fuses & breakers, this requires the value of fuse or breaker to be increased to avoid nuisance opening or tripping. A 1 amp slow blow should be used for 24VAC. A 0.25 amp slow blow should be used for 120VAC. A .125 amp slow blow should be used for 230V. SAFETY NOTES Wiring and installation must comply with all local electrical and mechanical codes. The actuator contains no components which the user can replace or repair. Cables are not plenum rated and require flex conduit. 1/2" Threaded Connector: Screw a conduit fitting into the actuator’s metal bushing. Jacket the actuator’s input wiring with suitable fl exible conduit. Properly terminate the conduit in a suitable junction box. 3/8" Flex Connector (-FC models): Mount the flexible conduit into the actuator’s metal bushing by means of the provided screw with a torque of 1.2 Nm. Jacket the actuator’s input wiring with suitable flexible conduit. Properly terminate the conduit in a suitable junction box.
CP65 Warning
⚠ WARNING: For Belimo Products sold in California, these Products do or may contain chemicals which are known to the State of California to cause cancer and or birth defects or other reproductive harms. For more information see www.p65warnings.ca.gov.

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