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T2-NF24A-SR-S2 • en • v1.1 • 04.2011 • Subject to changes
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Technical data sheet
NF24A-SR-S2
Modulating spring return actuator with
emergency function for adjusting air
dampers in ventilation and air conditioning
systems in buildings
• For air dampers up to approx. 2 m
2
• Tor�ue ��� Nm
Tor�ue ��� Nm
��� Nm
• Nominal voltage AC/DC 24 V
• Control�� modulating DC �� ... ��� V
Control�� modulating DC �� ... ��� V
• Position feedback DC 2 ... ��� V
• Two integrated auxiliary switches
Two integrated auxiliary switches
Technical data
Electrical data
Nominal voltage
AC 24 V, 50/60 Hz / DC 24 V
Nominal voltage range
AC 19.2 ... 28.8 V / DC 21.6 ... 28.8 V
Power consumption In operation
At rest
For wire sizing
3.5 W @ nominal torque
2.5 W
5.5 VA
Auxiliary switch
2 x SPDT, 1 mA ... 3 (0.5) A, AC 250 V
(1 x fix 10% / 1 x adjustable 10 ... 90%)
Connection Motor
Auxiliary switch
Cable 1 m, 4 x 0.75 mm
2
Cable 1 m, 6 x 0.75 mm
2
Functional data
Torque Motor
Spring return
Min. 10 Nm @ nominal voltage
Min. 10 Nm
Control Control signal Y
Operating range
DC 0 … 10 V, input impedance 100 k�
DC 2 … 10 V
Position feedback (measuring voltage U)
DC 2 … 10 V, max. 0.5 mA
Position accuracy
±5%
Direction of rotation Motor
Spring return
Reversible with switch
/
Can be selected by mounting L / R
Manual override
With hand crank and interlocking switch
Angle of rotation
Max. 95° , can be limited with
adjustable mechanical end stop
Running time Motor
Spring return
≤150 s (0 ... 10 Nm)
≤20 s @ –20 ... 50°C / max. 60 s @ –30°C
Sound power level Motor
Spring return
≤40 dB (A) @ 150 s running time
≤62 dB (A)
Service life
Min. 60,000 emergency positions
Position indication
Mechanical
Safety
Protection class
III
Extra low voltage
UL Class 2 Supply
Degree of protection
IP54
NEMA2, UL Enclosure Type 2
EMC
Low-voltage directive
CE according to 2004/108/EC
CE according to 2006/95/EC
Certification
Certified to IEC/EN 60730-1 and IEC/EN 60730-2-14
cULus according to UL 60730-1A and UL 60730-2-14
and CAN/CSA E60730-1:02
Mode of operation
Type 1.AA.B
Rated impulse voltage Actuator
Auxiliary switch
0.8 kV
2.5 kV
Control pollution degree
3
Ambient temperature
–30 ... +50°C
Non-operating temperature
–40 ... +80°C
Ambient humidity
95% r.h., non-condensating
Maintenance
Maintenance-free
Dimensions / Weight
Dimensions
See «Dimensions» on page 3
Weight
Approx. 2.0 kg
