Technical Data

285459

Power Supply

24 VAC, ±20%, 50/60 Hz, 24 VDC, -10% /

+20%

Power consumption in operation 2 W, 3 VA

Power consumption in rest

position

1.5 W, 2 VA

Transformer sizing

5 VA (class 2 power source)

Shaft Diameter

1/4...1/2” round, centers on 1/2”

Electrical Connection

18 GA appliance cable, 3 ft [1 m], with 1/2”

conduit connector

Overload Protection

electronic throughout 0...95° rotation

Electrical Protection

actuators are double insulated

Angle of rotation

95°

Torque motor

18 in-lb [2 Nm]

Direction of motion motor

selectable by ccw/cw mounting

Direction of motion fail-safe

reversible with cw/ccw mounting

Position indication

Mechanical

Running Time (Motor)

75 s @ 250°F [121°C]

Running time fail-safe

<25 s @ 32...122°F [0...50°C]

Ambient humidity

max. 95% r.H., non-condensing

Ambient temperature

32...122°F [0...50°C]

Storage temperature

-40...176°F [-40...80°C]

Degree of Protection

IP42, NEMA 2, UL Enclosure Type 2

Housing material

UL94-5VA

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.

California State Fire Marshal Listing 3210-

1593:104

Noise level, motor

45 dB(A)

Noise level, fail-safe

62 dB(A)

Servicing

maintenance-free

Quality Standard

ISO 9001

Weight

1.6 lb [0.60 kg]

Part no. Clamp side spring-return

FSTF120 US CW

FSTF120.1 US CW (bulk pack)

FSTF120.1 CCW CCW (bulk pack)

FSTF120-S US CW CW

FSTF120-S.1 US CW (bulk pack)

FSTF120-S.1 CCW CCW (bulk pack)

FSTF24-S.1 US CW (bulk pack)

† UL File XAPX.E108966

Torque 18 in-lb, 250°F for 30 min, for fire and smoke dampers

Application

The type FSTF 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. Square footage of operating damper will

depend on make and model per damper manufacturer UL testing.

Operation

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) typically 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.

Dimensions (Inches[mm])

Standard:

1/4" to 1/2"

1/4" to 5/16"

0.68" [16.7]

0.43" [11]

0.77" [19.5]

4.5" [114]

0.2" [5.2]

6.28" [159.5]

Safety Notes

Screw a conduit fitting into the actuator’s bushing. Jacket the actuator’s input

and output wiring with suitable flexible conduit. Properly terminate the conduit

in a suitable junction box.

Retrofit Safety Note

Use of the FSTF for replacement of other makes of actuators is limited in

damper area. The FSLF is preferred for direct coupled applications. The FSTF

may be applied for linkage applications on dampers 1.5 sq.ft. and smaller at

velocities under 2000 fpm.

FSTF24 US Technical Data Sheet

On/Off, Spring Return, Fail-Safe, AC/DC 24 V

800-543-9038 USA

866-805-7089 CANADA

203-791-8396 LATIN AMERICA / CARIBBEAN