Orange rectangular damper actuator with a metallic clamp at the top and a black electrical cord at the bottom.

LF24-SR US | Belimo | Actuators & Dampers

Damper Actuator, 35 in-lb, Spring Return, 24V, Modulating

Brand:Belimo

MPN:LF24-SR US

SKU:LF24-SR

List Price:

$749.00

Today's Price:

$389.48

product datasheet

installation instructions

catalog page

How To: Pre-Tension an Actuator on a Globe Valve

product specifications

Supply Va

5 VA

Power Supply

24 VAC,24 VDC

Torque

35 in-lb

Housing Material

Zinc Coated Steel

Humidity

max. 95% RH non-condensing

Input Impedance

100 k Ω for 2 to 10 VDC (0.1 mA), 500 Ω for 4 to 20 mA

Position Indication

visual indicator, 0° to 95° (0° is full spring return position)

Shaft Diameter

3/8 in to 1/2 in round, centers on 1/2 in

Quality Standard

ISO 9001

Power Supply Type

24V

Servicing

maintenance free

Power Consumption Running

2.5 W

Power Consumption Holding

1 W

Running Time

150 seconds

Unit of Measure

Transformer Sizing

5 VA (class 2 power source)

Storage Temperature Range

-40 to 176 °F (-40 to 80 °C)

Actuator Series

Ambient Temperature Range

-22 to 122 °F (-30 to 50 °C)

Application Type

Air

Angle of Rotation

95°

Agency Listings

cULus acc. To UL 873 and CAN/CSA C22.2 No. 24-93

Electrical Connection

3ft [1m], 18 GA plenum cable with 1/2 in conduit connector

Feedback Output U

2 to 10 VDC (max 0.7 mA) for 95°

Supply Voltage (Nominal)

24 VAC

Control Signal

Analog

product series specifications

Input Impedance: SR Models: 100 kΩ @ 0/2-10 VDC; 500 Ω @ 4-20 mA; MFT Models: 100 kΩ @ 0/2-10 VDC; 500 Ω @ 4-20 mA; 1500 Ω @ PWM, float, on/off

Motor: Brushless DC

Manual Override: Manual crank (except TF)

Wiring: TFB, LF: 3' (0.9 m) cable, 18 AWG, plenum rated (modulating models) - 3' (0.9 m) appliance cable (on/off, MFT, -S models); NFB, AFB, EFB: 3' (0.9 m) appliance cable, 18 AWG; NEMA 4: Terminal blocks inside housing

Conduit Connection: w/Cables: 1/2" NPT; NEMA 4: Four knockouts for waterproof conduit fittings

Feedback: 2-10 VDC (-SR and -MFT models only)

Auxiliary Switch: TFB, LF (-S): 1 SPDT, 3A @ 250V; NFB, AFB, EFB (-S): 2 SPDT, 3A @ 250V

Action: 2-Position: CW/CCW reversible mounting; Float/Prop.: DA/RA switch, CW/CCW rev. mt.

Spring Return Time: < 60 seconds

Rotation: 95°

Noise: TFB, LF, NFB: < 62 db; AFB: < 45 db; EFB: < 71.4 db

Resolution: 100 steps

Life Expectancy: 2-Position: 60,000 cycles; Float/Prop.: 60,000 cycles; 500,000 repositions

Operating Temperature: -22° to 122°F (-30° to 50°C); NEMA 4 models with heater option can go down to -40°C

Operating Humidity: 5 to 95% RH

Enclosure Rating: TFB: NEMA 2 (IP42); LF, NFB, AFB, EFB: NEMA 2 (IP54); NEMA 4: NEMA 4 (IP66)

Approvals: cULus, CE, RoHS

Warranty: 5 years

product series features

Symmetrical, reversible rotation design for installation flexibility
ISO 9001 manufacturing facility assures high quality
NEMA 4 Enclosure Rating for outdoor locations available on AFB, EFB and NFB models
Low power consumption for high efficiency and smaller transformer sizing
MFT models offer flexibility to customize and adapt a single actuator to various controllers and applications

more information & related documents

Series Description

The Belimo TFB, Belimo LF, Belimo NFB, Belimo AFB, and Belimo EFB Series direct-coupled air damper actuators provide control of dampers and valves for spring return applications. The damper actuators come in two-position, tri-state, proportional, and Multi-Function Technology (MFT) models. All include spring return to drive the damper or valve to a normal position when power is lost. Unique universal power supply models work with 24 Volt AC to 240 Volt AC or 24 Volt DC to 125 Volt DC. The new EFB Series is true spring return with a high 270 in-lb torque output and most models are available with optional NEMA 4 housing. It is possible to dual-mount EF actuators on one shaft, for a total of 540 in-lb. This actuator series is indispensable for Building Automation System BAS and HVAC applications. Kele also offers a number of accessories to work with Belimo spring return acuators.

Kele Description

ACT/SR/35INLB(4NM)/24V/PROP

Manufacturer

Belimo