The Belimo Sf series damper actuator has an open/close control type. It is a spring return actuators with an emergency function for adjusting air dampers in ventilation and air conditioning systems in buildings. It has an adjustable U-clamp, which accepts round or square shafts. This actuator can be installed with a pre-tensioned spring. This product is controlled with a standard signal of DC 0V to 10V and moves the damper to the operating position. This actuator is overload proof, requires no limit switches. It requires AC supply voltage between 19.2VAC and 264VAC and DC supply voltage between 21.6VDC and 137.5VDC.
It has 2 x SPDT integrated auxiliary switches

The direction of rotation reversible
Spindle driver universal spindle clamp
Operating voltage ranges between 2VDC and 10VDC
Running springtime is <20s
PVC connection cable length is 1m
Motor and return torque is 20Nm
Maximum damper area is 4m²
Damper spindle compatibility ranges between 10mm and 25.4mm
Power consumption is 7W
Noise level ≤45 (Motor) dBA, ≤62 (Spring Return) dBA
Rated impulse voltage is 0.8kV
Maintenance-free
Service life min. 60,000 emergency positions
Ambient temperature ranges between -30°C and 50°C

IEC/EN 60730-1
UL 60730-1A
UL 60730-2-14
CAN/CSA E60730-1:02
IP54