Why does the 12V fan spin at 5V?

Most motors have a wide tolerance of 5V-13V, though they may not start below ~7V.

Do more blades mean better performance?

More blades increase static pressure (good for radiators) but are louder. Fewer blades increase airflow (good for ventilation) with lower noise. 7-9 blades is typical.

How do I know if the fan is dying?

Listen for clicking/grinding, check RPM via software (far below spec is a red flag), or manually spin blades to check for wobble or stiffness.

38405mm Sleeve Bearing Brushless Cooling Centrifugal DC Blower

Name: 38*40*5mm Sleeve Bearing Brushless Cooling Centrifugal DC Blower
Brand: Fengxia Motor (Shanghai) Co., Ltd.
SKU: 2241817545

Shanghai, ChinaFengxia Motor (Shanghai) Co., Ltd.

38*40*5mm Sleeve Bearing Brushless Cooling Centrifugal DC Blower

US$2.50-3.00

1 Piece

Sample price:US$2.50/piece.Request sample

Product profile

Customization

Available

Material

Aluminum Fan

Blade Material

PBT 94ulv

Model NO.

4005 DC Blower

Type

DC Blower Fan

Electric Current Type

Mounting

Free Standing

Certification

RoHS, ISO, CE

Transport Package

Paper Box

Specification

38*40*5mm

Origin

China

Production Capacity

100000 Pieces/Year

Key features

Wide Voltage Tolerance: Operates reliably within 5V to 13V range, ensuring compatibility with various power sources.

Multi-Bearing Options: Available in sleeve, hydraulic, and double-ball bearings for different lifespan and noise needs.

Global Certifications: Compliant with RoHS, ISO, CE, and FCC standards for international market access.

Customization Services: Supports OEM/ODM, full customization from samples or designs to meet specific requirements.

Durable Construction: Aluminum fan with PBT 94ulv blades ensures long-term stable and durable product quality.

Versatile Applications: Suitable for UAVs, automotive, communication, medical, and refrigeration systems.

Professional Quality Control: 100% finished product inspection with visual and functional checks by 4 QA inspectors.

Fast Delivery: Standard lead time of one month for both peak and off-season production cycles.

Company profile

Importers and ExportersHigh Repeat Buyers Choice

Fengxia Motor (Shanghai) Co., Ltd.

Shanghai, China

CertifiedBusiness Type: Manufacturer/Factory & Trading Company CertifiedR&D Capacity: ODM Service Available & OEM Service Available CertifiedCustomization Options: Customization from Samples, Customization from Designs, etc. CertifiedExport Year: 5 Years CertifiedNearest Port: Shanghai PortAverage Response Time: ≤3.33h

AI-Powered supplier vetting

SummaryThe supplier demonstrates strong customization, R&D, OEM/ODM, quality-control, and complaint-handling capabilities. It reports new products within the past year, provides customization from samples and designs through full customization, and serves known brands through OEM. Production includes two lines, inventory capability, defined inspection procedures, and four QA/QC inspectors. However, important operational limitations exist: no available SDK, no overseas agents, branches, warehouse, or showroom, no offline trade-show participation, and only one experienced export-trade employee. Manufacturing controls also show gaps, including no ongoing quantity reconciliation for each batch and no standard operating procedure for outsourced manufacturing. Financial evidence is represented only by years rather than substantive indicators, so credibility cannot be determined. The supplier holds an ISO9001:2015 certificate, but the available information does not establish broader certification coverage.

Supplier typeThe supplier operates as a manufacturer with two production lines, provides OEM and ODM services, offers inventory capability, and accepts FOB and EXW quotations. It also provides full customization, but lacks overseas agents, branches, warehouses, and showrooms.

CertificationsThe supplier reports an ISO9001:2015 certificate. No additional specific certifications are identified in the provided information.

After-Sales capabilityThe supplier has documented and followed procedures for customer complaints and corrective/preventive actions, supporting an established service-response process. However, it has no overseas agents, branches, warehouse, or showroom, which limits demonstrated overseas service infrastructure.

R&D capabilityThe supplier reports new products in the past year, provides ODM services, and assigns R&D personnel to product development, design drawings, production support, and specifications. Nevertheless, it has no available SDK and no design input, output, review, validation, or confirmation documents available for audit.

Production capacityProduction evidence includes two production lines, inventory capability, one-month average lead times in both peak and off-season periods, four QA/QC inspectors, written finished-product inspection instructions, and multiple listed production machines. Controls are weakened by the absence of ongoing batch quantity reconciliation and a standard operating procedure for outsourced manufacturing.

Customization capabilityThe supplier explicitly supports customization from samples, customization from designs, and full customization, with the same capability reported under both R&D and design services. This directly demonstrates broad customization coverage.

Product Q&A

Q:What causes fan noise and how to fix it?

Check for loose screws causing vibration, remove dust buildup, lower RPM via BIOS, or consider bearing type (sleeve is quietest but wears faster).

Q:Which direction should the fan face?

Follow arrows on the frame: intake for front/side, exhaust for rear/top. Tower coolers push air toward rear exhaust.

Q:What is the difference between 3-pin and 4-pin connectors?

3-pin uses DC voltage control; 4-pin uses PWM for automatic, quieter, and more precise speed control. 4-pin fits 3-pin headers but runs at full speed.

Q:How long will the fan last?

Sleeve bearing lasts ~2-3 years, hydraulic ~4-5 years, and double-ball bearing lasts 5-10 years with 24/7 tolerance.

Q:How can I make the fan quieter?

Use rubber grommets, install inline resistors to drop voltage, or adjust BIOS fan curves to keep RPM low until temperatures rise.