FB3G250-24PL-91 DC Backward Centrifugal Fan, 24VDC, 250mm, 1475.0 m3/h

Brief Description

The FB3G250-24PL-91 is a 24VDC high-static-pressure DC backward centrifugal fan that delivers an exceptional 885 Pa at 1475.0 m³/h — industrial-grade static pressure from a standard low-voltage DC power source. Operating at 2950 RPM, this 250mm fan pushes the performance envelope for 24V centrifugal fans, making it ideal for high-resistance ducted systems, HEPA filtration, and applications where substantial back pressure must be overcome without stepping up to higher voltage systems. The BLDC92 brushless motor achieves this while drawing 8.0A at 192W, with integrated FG tach output enabling precision closed-loop speed control. Compatible with 0-10VDC analog and PWM digital control signals, the fan integrates seamlessly into automated ventilation systems. With IP44-rated ingress protection, Class B insulation, and a 50,000-hour L10 service life, this fan is engineered for demanding industrial, telecom, and cleanroom applications requiring high pressure from low-voltage DC power. CE and RoHS certified.

Product Specification

At the heart of the FB3G250-24PL-91 is a BLDC92 external rotor brushless DC motor driving a backward curved centrifugal impeller with a 250mm diameter, optimized for high-pressure operation at 2950 RPM. The aerodynamic design achieves 75-80% efficiency, converting 192W of DC power into 1475.0 m³/h of airflow against an impressive 885 Pa static pressure — pressure performance that competes with 48V and even 310VDC systems. The 8.0A current draw at 24VDC nominal (16-28 VDC range) enables operation from standard deep-cycle battery banks and high-capacity DC power supplies commonly found in telecom and industrial installations. Its comprehensive control interface accepts 0-10VDC analog signals and PWM (1-10kHz) digital inputs for stepless speed regulation, while the FG tachometer output delivers real-time RPM feedback for closed-loop integration with PLC, microcontroller, or building management systems. Built-in protection features include soft-start, current limiting, locked-rotor protection, and reverse polarity protection. The fan construction features a die-cast aluminum housing with IP44-rated sealing, ball bearings supporting any mounting orientation, and Class B electrical insulation for safe operation up to 130°C ambient. Rated for 50,000 hours L10 lifespan at 40°C with minimal maintenance, this fan is purpose-built for applications where high static pressure must be delivered from low-voltage DC power with uncompromising reliability.

Nominal Date

DC Backward Centrifugal Fan
Type	FB3G250-24PL-91
Model	BLDC92

Connection diagram

Remarks:

I. Standard lead wire length is 300mm; customized length available upon request.

II. Control via 0-10VDC analog signal or PWM digital signal.

Product drawing

Aerodynamic Performance Charts

Test condition:

I. Measurement performed according to ISO 5801, using double chamber method.

II. Test voltage: 24VDC, ambient temperature: 23±2°C, relative humidity: 50±10%.

III. Noise measured at 1m distance in anechoic chamber per ISO 3744.

IV. PQ curve shows performance across 0-100% duty cycle at rated voltage.

Safety Requirements

I. When taking out the fan, do not directly lift the fan lead wire. If the lead wire is excessively stressed, the internal welding part may fall off

II. Do not plug or unplug the fan lead plug when the fan is running

III. If the fan does not work after starting, do not touch the impeller, rotor, or other parts, professional technical personnel are required to inspect the fan to prevent sudden start of the fan from causing hand or other personal injury

IV. Because of the soft start characteristics of the fan, to prevent personal injury, do not touch the impeller or other parts of the fan during powered on or running at low speeds

V. The fan needs to be operated and used under the guidance of professional personnel to prevent children from coming into touch this product

VI. If the power line is worn or damaged, it needs to be returned to the manufacturer for repair or be replaced under the guidance of the manufacturer

VII. As a part of the fan, it is not recommended to use the motor alone when there is no impeller or loading

Advantages

1. Industrial-Grade Static Pressure at 24VDC: The FB3G250-24PL-91 achieves an exceptional 885 Pa at 1475.0 m³/h on only 24VDC — pressure performance that rivals 48V and 310VDC systems. This enables high-resistance ducted ventilation, HEPA filtration, and cleanroom pressurization from standard low-voltage DC power infrastructure.

2. High-Speed Aerodynamic Efficiency: 75-80% aerodynamic efficiency at 2950 RPM through precision backward curved impeller design, converting 192W into substantial airflow against high back pressure — 30-40% energy savings versus equivalent AC centrifugal fans requiring 3-phase power.

3. Wide Application Range: Ideal for telecom shelter pressurization, cleanroom HEPA filtration, industrial fume extraction with long duct runs, data center rack cooling, and any application where high static pressure must be delivered from battery or DC bus power. Available for OEM/ODM customization.

4. Robust & Sustainable: EC brushless motor reduces energy consumption by 30%+ versus AC alternatives. Die-cast aluminum IP44 housing, ball bearings, and 50,000-hour L10 lifespan at 40°C ensure minimal lifecycle cost and replacement frequency.

5. Precision Integration: 0-10VDC/PWM control plus FG tach feedback enable seamless PLC and BMS integration. Standard 250mm flange, any-orientation mounting, and maintenance-free BLDC design simplify installation and eliminate ongoing service requirements.

FAQ

Q1: What kind of payments do you support?

A1: For sample order, 100% payment in advance; For batch order, 30% in advance and 70% will be paid before shipping

Q2: Will you provide samples?

A2: Sample is available and can be delivered within 7 days for standard models

Q3: How can I choose a more suitable model?

A3: We need the information like fan type, quantity, size, material, voltage, air flow and static pressure.

Q4: How can I place the order?

A4: Usually quote you within 24 hours after we get your inquiry. First sign the PI, pay deposit, then we will arrange the production. After finished production need you pay balance. Finally we will ship the Goods.

Q5: About transportation

A5: All available shipping ways could be applied, express shipping, air or sea. Appointed shipping company or our own forwarders all could be used in shipment. Full-way tracking the cargos for you before the goods arrive.

Q6: How long is the warranty period?

A6: We currently offer 3-year quality guarantee for our own products, and in response to current product problems, our company provides line support, and some customers have been able to improve their products.