NFB24-SR-S

$434.70

Each

Damper Actuator, 90 in-lb [10 Nm], Spring return, AC/DC 24 V, DC 2…10 V, 2 x SPDT

Fail-safe position

or sign up for a free membership to get our lowest pricing.

Weight 5.3 lbs
Torque

90 in-lb [10 Nm]
Brand

Belimo
Voltage

AC/DC 24 V
Auxiliary Switch

2 SPDT
Actuator Type

Spring return
Control type

Modulating
Torque motor
90 in-lb [10 Nm]
Power consumption in operation
3.5 W
Power consumption in rest position
2.5 W
Transformer sizing
6 VA (class 2 power source)
Ambient humidity
5...95% r.H. non-condensing
Housing material
zinc coated metal and plastic casing
Electrical Connection
(2) 18 GA appliance cables with 1/2" conduit connectors, 3 ft [1 m],
Auxiliary switch
2 x SPDT, 3A resistive (0.5A inductive) @ 250 VAC, one set at 10°, one adjustable 10...90°
Manual override
5 mm hex crank (3/16" Allen), supplied
Angle of rotation
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]
Control
Modulating
Control operating range Y note
4...20 mA w/ ZG-R01 (500 Ω, 1/4 W resistor)
Position Feedback
DC 2...10 V, Max. 0.5 mA
direction of rotation motor
reversible with built-in switch
Overload Protection
electronic throughout 0° to 95° rotation
Input Impedance
100 kΩ for DC 2...10 V (0.1 mA), 500 Ω for 4...20 mA
Degree of Protection
IP54, NEMA 2, UL Enclosure Type 2
Nominal voltage
AC/DC 24 V
Nominal voltage frequency
50/60 Hz
Power Supply
24 VAC, ±20%, 50/60 Hz, 24 VDC, -10% / +20%
Power supply tolerance AC
±20%
Power supply tolerance DC
-10% / +20%
Agency Listing
cULus acc. to UL60730-1A/-2-14, CAN/CSA E60730-1:02, CE acc. to 2004/108/EC and 2006/95/EC
Operating Range
DC 2...10 V, 4...20 mA w/ ZG-R01 (500 Ω, 1/4 W resistor)
Emergency control function
Spring Return
Product family
Damper Actuator
direction of rotation spring-return
reversible with cw/ccw mounting
Noise level, motor
≤40 dB (A) 
Shaft Diameter
1/2" to 1.05" round, centers on 1/2" and 3/4" with insert, 1.05" without insert
Electrical accessories
ADS-100|IRM-100|P475|P475-1|PS-100|PTA-250|SGA24|SGF24|TF-CC US|ZG-R01|ZG-R02|ZG-SGF|ZG-X40
Family Series
NF Series
Noise Level (Fail-Safe)
<62 dB (A) 
Running time (Fail-Safe)
<20 seconds
Running Time (Motor)
95 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
Modulating
Connection
cable
Degree of protection IEC/EN
IP54
Degree of protection NEMA/UL
NEMA 2
Enclosure
UL Enclosure Type 2
Auxiliary Switch
2 SPDT
CAD ThomasNetLink
NFB24-SR-S
Product Features
Torque min. 90 in-lb, for control of air dampers.
Electrical Protection
actuators are double insulated
VA Rating
6
Mechanical accessories
AF-P|AV8-25|IND-AFB|K7-2|KG10A|KG8|KH10|KH12|KH8|KH-AFB|SH10|SH8|TOOL-06|Z-AF|ZG-100|ZG-101|ZG-109|ZG-110|ZG-118|ZG-120|ZG-AFB|ZG-AFB118|ZG-DC1|ZG-DC2|ZG-JSA-1|ZG-JSA-2|ZG-JSA-3|ZS-100|ZS-101|ZS-150|ZS-260|ZS-300|ZS-300-5|ZS-300-C1|ZS-300-C2|ZS-300-C3|Z-SF
Operation
The NF..24-SR-S 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 NF..24-SR-S series provides 95° of rotation and is provided with a graduated position indicator showing 0° to 95°. The NF..24-SR-S uses a brushless DC motor which is controlled by an Application Specific Integrated Circuit (ASIC) and a microprocessor. The microprocessor provides the intelligence to the ASIC to provide a constant rotation rate and to know the actuator’s exact fail-safe position. The ASIC monitors and controls the brushless DC motor’s rotation and provides a digital rotation sensing function to prevent damage to the actuator in a stall condition. The actuator may be stalled anywhere in its normal rotation without the need of mechanical end switches. The NF..24-SR-S 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 adjustable between 10° to 90°. The NF..24-SR-S actuator is shipped at 5° (5° from full fail-safe) to provide automatic compression against damper gaskets for tight shut-off.
Application
For fail-safe, modulating control of dampers in HVAC systems. Actuator sizing should be done in accordance with the damper manufacturer’s specifications. 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. The actuator operates in response to a 2 to 10 VDC or, with the addition of a 500Ω resistor, a 4 to 20 mA control input from an electronic controller or positioner. A 2 to 10 VDC feedback signal is provided for position indication. Not to be used for a master-slave application.
Typical Specification
Spring return control 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 actuator must provide modulating damper control in response to a 2 to 10 VDC or, with the addition of a 500Ω resistor, a 4 to 20 mA control input from an electronic controller or positioner. The actuators must be designed so that they may be used for either clockwise or counter clockwise fail-safe operation. Actuators shall use a brushless DC motor controlled by a microprocessor and be protected from overload at all angles of rotation. Run time shall be constant, and independent of torque. A 2 to 10 VDC feedback signal shall be provided for position feedback. 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.

Datasheet Download: Datasheet

Installation instructions Download: Installation instructions

Need Help?

Call one of our experts 1-888-423-2525

Monday-Friday EST 6:00am - 4:00pm