LMB24-SR: Belimo Modulating 24V w/ 2-10VDC

Submittal Form
SKU: Belimo LMB24-SR Category: Tag:


For proportional modulation 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 from 1/4” up to 5/8” in diameter by means of its universal clamp. Shafts up to 3/4” diameter can be accommodated by an accessory clamp.

The actuator operates in response to a 2 to 10 VDC, or with the addition of a 500 7 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 or master-slave applications.


The actuator is not provided with and does not require any limit switches, but is electronically protected against overload. The anti-rotation strap supplied with the actuator will prevent lateral movement.

The LMB series provides 95° of rotation and a visual indicator indicates position of the actuator. When reaching the damper or actuator end position, the actuator automatically stops. The gears can be manually disengaged with a button on the actuator cover.

The LMB24-SR… actuators use a sensorless Brushless DC motor, which is controlled by an Application Specific Integrated Circuit (ASIC). The ASIC monitors and controls the actuator’s rotation and provides a digital rotation sensing (DRS) function to prevent damage to the actuator in a stall condition. Power consumption is reduced in holding mode.

Add on auxiliary switches or feedback potentiometers are easily fastened directly onto the actuator body for signaling and switching functions.

Additional information

Power Supply

24 VAC ± 20% 50/60 Hz
24 VDC ± 10%

Power Consumption

1.5 W (0.4 W)

Transformer Sizing

1.5 W (0.4 W)

Electrical Connection

3 ft, 18 GA plenum rated cable
1/2” conduit connector
Protected NEMA 2 (IP54)

Overload Protection

electronic througho2 to 10 VDC, 4 to 20 mAut 0 to 95° rotation

Operation Range Y

2 to 10 VDC, 4 to 20 mA

Input Impedance

100 k7 (0.1 mA), 500 7

Feedback Output U

2 to 10 VDC (max 0.5 mA)

Angle of Rotation

max. 95°, adjust. with mechanical stop


45 in-lb [5 Nm]

Direction of Rotation

Reversible with ↷/↶ Switch
Actuator will move:
↶=CCW with decreasing control signal (10 to 2V)
↷=CW with decreasing control signal (10 to 2V)

Position Indication

reflective visual indicator (snap-on)

Manual Override

external push button

Running Time

95 seconds, constant independent of load


5 to 95% RH non condensing (EN 60730-1)

Ambient Temperature

5 to 95% RH non condensing (EN 60730-1)

Storeage Temperature

5 to 95% RH non condensing (EN 60730-1)


5 to 95% RH non condensing (EN 60730-1)

Housing Material


Agency Listings†

cULus acc. to UL 60730-1A/-2-14,
CAN/CSA E60730-1:02,
CE acc. to 2004/108/EEC and 2006/95/EC

Noise Level



maintenance free

Quality Standard

ISO 9001


1.7 lbs [0.5 Kg]