FB3G250-48PL-91 DC Backward Centrifugal Fan, 48VDC, 250mm, 1475 m3/h

The FB3G250-48PL-91 is a 48VDC high-static-pressure DC backward centrifugal fan that combines telecom-standard voltage with industrial-grade pressure performance. Delivering 885 Pa at 1475 m³/h, it provides substantial pressure headroom for high-resistance ducted systems, HEPA filtration, and telecom infrastructure ventilation. The BLDC92 brushless motor operates at 2950 RPM drawing 4.0A at 192W, with an integrated FG tach output for precision closed-loop speed control. Compatible with 0-10VDC analog and PWM digital signals, it integrates seamlessly with DCIM, BMS, and industrial automation platforms. Its wide 16-56 VDC input range ensures stable operation across telecom -48VDC plant voltage variations and battery-backed DC systems. With IP44 ingress protection, Class B insulation, and 50,000-hour L10 service life, this fan is engineered for demanding 48VDC applications requiring high static pressure. Ideal for telecom shelter pressurization, HEPA-filtered equipment cooling, industrial process extraction, and data center airflow management. CE and RoHS certified.

At the core of the FB3G250-48PL-91 is a BLDC92 external rotor brushless DC motor driving a backward curved centrifugal impeller with a 250mm diameter, optimized for high-pressure 48VDC operation at 2950 RPM. The aerodynamic design achieves 75-80% efficiency, converting 192W of 48VDC power into 1475 m³/h at an impressive 885 Pa — delivering static pressure performance that maximizes the capability of standard telecom -48VDC bus power. The motor's 4.0A current draw across a wide 16-56 VDC range ensures compatibility with telecom DC plants, solar-battery hybrid systems, and DC microgrid installations where voltage may fluctuate. 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. Built-in protection features include soft-start, current limiting, locked-rotor protection, and reverse polarity protection. The fan features a die-cast aluminum housing with IP44-rated sealing, ball bearings for any mounting orientation, and Class B electrical insulation for safe operation to 130°C ambient. Rated for 50,000 hours L10 lifespan at 40°C, this fan is the optimal choice for 48VDC systems demanding high static pressure with DC-native power efficiency.

DC Backward Centrifugal Fan
Type	FB3G250-48PL-91
Model	BLDC92

Remarks:

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

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

Test condition:

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

II. Test voltage: 48VDC, 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.

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

1. High Static Pressure on 48VDC: The FB3G250-48PL-91 achieves an impressive 885 Pa at 1475 m³/h on standard telecom -48VDC power — delivering substantial pressure headroom for high-resistance ducted ventilation, HEPA filtration, and pressurized enclosure cooling without AC inverters.

2. Efficient BLDC92 Performance: 75-80% aerodynamic efficiency at 2950 RPM, converting 192W into 1475 m³/h at 885 Pa — 30-40% energy savings versus equivalent AC fans while operating natively from 48VDC infrastructure.

3. Telecom & Industrial Applications: Purpose-built for telecom shelter pressurization, HEPA-filtered equipment cooling, industrial process extraction, DC microgrid ventilation, and data center airflow management. OEM/ODM available.

4. Reliable Continuous Operation: Die-cast aluminum IP44 housing, ball bearings, over-temperature protection, 50,000-hour L10 lifespan at 40°C, and 3-year warranty for mission-critical 48VDC deployments.

5. DCIM-Ready Control: 0-10VDC/PWM plus FG tach feedback for DCIM/BMS integration. Standard 250mm flange, any-orientation mounting, maintenance-free BLDC.

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.