EFX120-S N4



Damper Actuator, 270 in-lb [30 Nm], Spring return, AC 100…240 V / DC 100…125 V, On/Off, 2 x SPDT, NEMA 4

Fail-safe position
Weight 12 lbs

270 in-lb [30 Nm]




AC 100…240 V / DC 100…125 V

Auxiliary Switch


Actuator Type

Spring return

Control type


Torque motor
270 in-lb [30 Nm]
Power consumption in operation
9.5 W
Power consumption in rest position
4.5 W
Transformer sizing
21 VA @ 100 VAC, 29 VA @ 240 VAC
Ambient humidity
5...95% r.H. non-condensing
Housing material
Aluminum die cast and plastic casing
Electrical Connection
Terminal block(s) inside junction box with knockouts
Auxiliary switch
2 x SPDT, 3A resistive (0.5A inductive) @ 250 VAC, one set at 10°, one set at 85°
Manual override
5 mm hex crank (3/16" Allen), supplied
Angle of rotation
Max. 95°, adjustable with mechanical end stop, 35...95°
Position indication
visual indicator, 0° to 95° (0° is full spring return position)
Ambient temperature
-22...122°F [-30...50°C]
Non-operating temperature
-40...176°F [-40...80°C]
direction of rotation motor
reversible with CW/CCW mounting
Overload Protection
electronic throughout 0° to 95° rotation
Degree of Protection
IP66, NEMA 4, UL Enclosure Type 4
Nominal voltage
AC 100...240 V / DC 100...125 V
Nominal voltage frequency
50/60 Hz
Power Supply
100...240 VAC, -20% / +10%, 50/60 Hz, 100...125 VDC, ±10%
Power supply tolerance AC
-20% / +10%
Power supply tolerance DC
Agency Listing
cULus acc. to UL60730-1A/-2-14, CAN/CSA E60730-1:02, CE acc. to 2004/108/EC and 2006/95/EC
Emergency control function
Spring Return
Product family
Damper Actuator
direction of rotation spring-return
reversible with cw/ccw mounting
Noise level, motor
≤56.5 dB (A) 
Shaft Diameter
1/2" to 1.05" round, centers on 3/4" with insert, 1.05" without insert
Electrical accessories
Mechanical accessories
Family Series
EF Series
Noise Level (Fail-Safe)
≤71 dB (A) 
Running time (Fail-Safe)
<20 seconds
Running Time (Motor)
75 sec
Running Time (Fail-Safe)
<20 sec @ -4...122°F [-20...50°C], <60 sec @ -22°F [-30°C]
Fail-Safe function
Spring return
Control type
Degree of protection IEC/EN
Degree of protection NEMA/UL
UL Enclosure Type 4
Auxiliary Switch
CAD ThomasNetLink
EFX120-S N4
Product Features
Torque min. 270 in-lb, for control of air dampers
Electrical Protection
actuators are double insulated
The EF..120-S N4 series actuators provide true spring return operation for reliable fail-safe application and positive close off on air tight dampers. The spring return system provides constant torque to the damper with, and without, power applied to the actuator. The EF..120-S N4 series provides 95° of rotation and is provided with a graduated position indicator showing 0° to 95°. The actuator may be stalled anywhere in its normal rotation without the need of mechanical end switches. The EF..120-S N4 versions are provided with two built-in auxiliary switches. These SPDT switches provide safety interfacing or signaling, for example, for fan start-up. The switching function at the fail-safe position is fixed at 10°, the other switch function is fixed at 85°. The EF..120-S N4 actuator is shipped at 5° (5° from full fail-safe) to provide automatic compression against damper gaskets for tight shut-off. Installation Note: Use 60°C/75°C copper (CU) conductor and wire size range 12-26 AWG, stranded or solid. If conduit is used, use flexible metal conduit; UL listed and CSA certified strain relief or conduit fitting suitable for outdoor applications, rated NEMA type 4, 4X, 6 or 6X or watertight.
For On/Off, fail-safe control of dampers in HVAC systems. Actuator sizing should be done in accordance with the damper manufacturer's specifications. Control is On/Off from an auxiliary contact or a manual switch. The actuator is mounted directly to a damper shaft up to 1.05" in diameter by means of its universal clamp. A crank arm and several mounting brackets are available for applications where the actuator cannot be direct coupled to the damper shaft. Maximum of two EF's can be piggybacked for torque loads of up to 540 in-lbs. Minimum 3/4" diameter shaft and parallel wiring.
Typical Specification
On/Off spring return damper actuators shall be direct coupled type which require no crank arm and linkage and be capable of direct mounting to a jackshaft up to a 1.05” diameter. The actuators must be designed so that they may be used for either clockwise or counter clockwise fail-safe operation. Actuators shall be protected from overload at all angles of rotation. If required, two SPDT auxiliary switch shall be provided. Actuators with auxiliary switches must be constructed to meet the requirements for Double Insulation so an electrical ground is not required to meet agency listings. Actuators shall be cULus listed and have a 5 year warranty, and be manufactured under ISO 9001 International Quality Control Standards. Actuators shall be as manufactured by Belimo.
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.

Installation instructions Download: Installation instructions

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