FB3G250-48PL-90 DC Backward Centrifugal Fan, 48VDC, 250mm, 1132 m3/h

The FB3G250-48PL-90 is a 48VDC quiet-operation DC backward centrifugal fan designed for telecom and industrial DC bus applications where low noise is essential. Operating at just 66 dB(A) at full speed — well below normal conversation level — it delivers 1132 m³/h at 508 Pa while consuming only 85W. The BLDC92 brushless motor drives the 250mm backward curved impeller at 2150 RPM, with integrated FG tach output for precision speed feedback in closed-loop control systems. Its 16-56 VDC input range and low 1.75A current draw make it ideal for telecom -48VDC plants, DC microgrids, and battery-backed ventilation systems. Compatible with 0-10VDC analog and PWM digital control, it integrates seamlessly with DCIM and BMS platforms. IP44-rated with Class B insulation and 50,000-hour L10 lifespan, this fan is purpose-built for continuous quiet operation in noise-sensitive infrastructure. Ideal for telecom shelter ventilation, data center rack cooling, office HVAC, laboratory extraction, and residential energy-recovery systems. CE and RoHS certified.

At the core of the FB3G250-48PL-90 is a BLDC92 external rotor brushless DC motor driving a backward curved centrifugal impeller with a 250mm diameter, optimized for quiet high-efficiency operation at 2150 RPM. The aerodynamic design achieves 75-80% efficiency, converting just 85W of 48VDC power into 1132 m³/h at 508 Pa — delivering whisper-quiet 66 dB(A) performance while achieving 30-40% energy savings versus equivalent AC centrifugal fans. The motor's low 1.75A current draw across a wide 16-56 VDC range ensures compatibility with telecom -48VDC plants, solar-battery hybrid systems, and DC microgrid 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. 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 optimized for 48VDC applications requiring silent, efficient, and reliable air movement.

DC Backward Centrifugal Fan
Type	FB3G250-48PL-90
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. Whisper-Quiet 48VDC Operation: The FB3G250-48PL-90 operates at just 66 dB(A) at full speed — well below normal conversation — delivering 1132 m³/h at 508 Pa on standard telecom -48VDC power. Ideal for noise-sensitive infrastructure where both DC compatibility and acoustic comfort are required.

2. Ultra-Efficient Low-Power Design: 75-80% aerodynamic efficiency, consuming only 85W at 1.75A from 48VDC — representing 30-40% energy savings versus equivalent AC fans. The BLDC92 motor achieves 1132 m³/h per 85W for exceptional air-moving efficiency.

3. Wide Application Range: Perfect for telecom shelter ventilation, data center rack cooling, office HVAC systems, laboratory fume extraction, and residential energy-recovery ventilators. Available for OEM/ODM customization.

4. Sustainable & Reliable: EC brushless motor cuts energy use by 30%+ versus AC. Die-cast aluminum IP44 housing, ball bearings, and 50,000-hour L10 lifespan at 40°C ensure low lifecycle cost and minimal maintenance.

5. Seamless DCIM Integration: 0-10VDC/PWM control plus FG tach feedback for DCIM/BMS closed-loop monitoring. Standard 250mm flange, any-orientation mounting, maintenance-free BLDC design.

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.