J20741 - Subject to change. © Belimo Aircontrols (USA), Inc.
Torque min. 35 in-lb, for control of air dampers
Application
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 auxil-
iary contact, or a manual switch.
The actuator is mounted directly to a damper shaft from 3/8”
up to 1/2” in diameter by means of its universal clamp, 1/2”
shaft centered at delivery. For shafts up to 3/4” use K6-1
accessory. A crank arm and several mounting brackets are
available for applications where the actuator cannot be direct
coupled to the damper shaft.
Operation
The LF 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 consistent torque
to the damper with, and without, power applied to the actuator.
The LF 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. Power con-
sumption is reduced in holding mode. The actuator is double
insulated so an electrical ground connection is not necessary.
The LF120-S US and LF230-S US versions are provided with
1 built-in auxiliary switch. This SPDT switch is provided for
safety interfacing or signaling, for example, for fan start-up.
The switching function is adjustable between 0° and 95°.
Dimensions
[All numbers in brackets are in millimeters.]
LF120 (-S) US / LF230 (-S) US
On-off, Spring Return Fail-Safe, 120/230 VAC
Technical Data LF120 (-S) US LF230 (-S) US
Power supply 120 VAC ± 10% 230 VAC ± 10%
50/60 Hz 50/60 Hz
Power consumption running: 5.5 W 5 W
holding: 3.5 W 3 W
Transformer sizing 7.5 VA 7 VA
Electrical connection 3 ft, 18 GA appliance cable
(-S models have 2 cables)
1/2” conduit connector
Overload protection electronic throughout 0 to 95° rotation
Electrical protection actuators are double insulated
Angle of rotation max 95°, adjust. with mechanical stop
Torque 35 in-lb [4 Nm] constant torque
Direction of rotation reversible with cw/ccw mounting
Position indication visual indicator, 0° to 95° (0° is
spring return position)
Auxiliary switch 1 x SPDT 3A (0.5A) @ 250 VAC,
UL listed
(-S models) adjustable 0° to 95°
Electrical protection actuators are double insulated
Running time motor: < 40 to 75 sec
spring:< 25 sec
@-4°F to +122°F [-20°C to +50°C]
< 60 sec
@-22°F [-30°C]
Humidity 5 to 95% RH non-condensing
Ambient temperature -22°F to +122°F [-30°C to +50°C]
Storage temperature -40°F to +176°F [-40°C to +80°C]
Housing NEMA type 2 / IP54
Housing material zinc coated steel
Agency listings UL 873, CSA C22.2 No. 24 Certified,
CE [LF230(-S) US]
Noise level max: running < 50 db (A)
spring return 62 dB (A)
Servicing maintenance free
Quality standard ISO 9001
Weight LF120/230 3.4 lbs (1.54 kg)
LF120/230-S 3.5 lbs (1.60 kg)
TEMP. IND &
REG. EQUIP.