An EC (Electronically Commutated) fan uses a brushless DC motor with onboard electronic commutation, allowing infinite speed control via 0–10 V, PWM, or Modbus signals while reaching 88–93% wire-to-air efficiency. An AC fan uses a fixed-speed or triac-dimmable AC induction motor, typically 55–75% efficient. EC fans cost more upfront but save 30–50% on energy and 70–90% on noise at part-load.

Centrifugal fans move air perpendicular to the impeller axis — high static pressure (up to 3.2 kPa), used in AHUs, dust collection, heat exchangers. Axial fans move air parallel to the axis — low static (200–600 Pa), high airflow, ideal for free cooling, condensers, ventilation. Cross-flow fans move air across the impeller — used in fan-coil units and AC indoor units for wide even flow at low pressure.

A plug fan is a centrifugal fan without a scroll housing — the impeller mounts directly into a plenum or AHU section. Typically backward-curved with EC motors (called "Plenum Fans" or "FanGrid arrays"). Allows flexible installation, multi-fan N+1 redundancy, and lower system effect losses. LONGWELL LWBE3G is a plug fan family.

Forward-curved (FC): cheap, compact, high airflow at low pressure, max ~65% η, noisy, used in residential HVAC, small AC units. Backward-curved (BC): expensive, higher static pressure, max 88–93% η, quieter, used in AHUs, FFU, plug fans, professional HVAC. Backward-curved EC plug fans dominate professional HVAC + data center.

FanGrid is an array of multiple smaller EC plug fans (typically 4, 6, 9, or 16) replacing one large belt-drive AC fan in a CRAH or AHU. Benefits: N+1 redundancy without standby unit, lower total noise, easier maintenance (hot-swap), better part-load efficiency. Widely used in data center CRAH retrofit and large AHU programs.

LONGWELL EC fans are rated L10 = 60,000 hours (~6.8 years 24/7) and L50 = 90,000 hours at 40°C ambient. With 50% load duty at 25°C ambient, real-world MTTF exceeds 120,000 hours (>13 years). Bearings are sealed-for-life; electronic boards conformal-coated.

Five-step selection: (1) Calculate required airflow CFM/m³h from sensible heat load and ΔT. (2) Calculate system static pressure (filter + coil + damper + ductwork losses). (3) Plot operating point on fan PQ curve, prefer BEP at 70–90% max RPM for noise headroom. (4) Verify motor full-load amps fit AHU breaker. (5) Choose IP rating per environment (IP54 indoor, IP55 outdoor, IP67 wet/coastal). LONGWELL Selection Center automates this.

SFP = electrical power input ÷ air volume flow. Unit: W per L/s. SFP captures installed efficiency including motor + drive losses, not just peak fan η. Targets: SFP <0.5 W/L/s excellent (EC at BEP), 0.5–0.8 good (AC backward), >1.5 poor (forward AC). EU ErP Lot 6 sets SFP limits for fans >125 W.

BEP is the operating point on a fan PQ curve where wire-to-air efficiency is highest. Operating away from BEP wastes energy and increases noise. Rule: design system pressure curve to cross fan PQ at 80–95% of BEP airflow. EC fans hold BEP across a wider range than AC because variable speed shifts the operating point with load.

Wire-to-air η = useful air power (m³/s × Pa) ÷ electrical input power (W). Includes ALL losses: motor, drive, bearing, aerodynamic. Different from 'motor efficiency' (motor loss only) or 'fan total η' (excludes motor). LONGWELL LWBE3G measures 88–90% wire-to-air per AMCA 210/211.

P (W) = (V × Pa) / (η × 1000), where V = airflow m³/s, Pa = static pressure, η = wire-to-air efficiency. Example: 1.5 m³/s at 800 Pa at 88% η → P = 1,364 W ≈ 1.4 kW. Use LONGWELL Selection Center to verify operating point on actual PQ curve.

Sound power Lw (dB) is absolute acoustic energy emitted, measured in reverberation room per ISO 13347. Sound pressure Lp (dB(A)) is what's measured at a distance — depends on room, distance, reflections. For BMS calc, use Lw. For 'will neighbors hear it?' use Lp at expected distance.

LONGWELL EC motors use sensorless field-oriented control (FOC) with PMSM (permanent-magnet synchronous motor) topology. Rotor position estimated from back-EMF, eliminating Hall sensors and improving reliability. Commutation at 16–20 kHz IGBT switching.

Noise floor at 30% speed @ 1 m: LWBE3G-355 = 36 dB(A), LWBE3G-500 = 38 dB(A), LWAE3G-630 = 40 dB(A). Full-load Lw rises to 78–88 dB(A) by size and load. Octave-band sound power Lw per ISO 13347 provided on every datasheet.

Yes. LONGWELL Selection Center provides AMCA 210/211 PQ curves, ISO 13347 sound power Lw (octave band), CFD-validated efficiency maps, system effect coefficients. Web-based, free-to-use, exports BIM-compatible reports.

Yes. HALT (Highly Accelerated Life Test) and HASS reports provided for OEM volume programs. Profiles: temperature −40°C to +85°C, vibration 5–50 Hz per IEC 60068-2-64, accelerated bearing life per ISO 281.

CE (LVD + EMC), UL/cUL recognition, TÜV component approval, ATEX (II 3D Ex tc T125°C on dedicated SKU), VDE, EAC, RoHS, REACH, FCC, CCC, ISO 9001/14001/45001, BSCI, Passivhaus PHI on residential ERV, HVI 920, ErP Lot 6 (2026), GB/T 18801, Matter 1.2 (smart home).

Yes. ATEX Group II Category 3D Ex tc T125°C IIIC for dust-explosive (zone 22). LWBE3G-ATEX and LWHV-ATEX lines are zone 21/22 certified. Zone 1/2 gas-explosive on dedicated OEM programs.

IP55 = dust protected + water jets from any direction. IP67 = dust-tight + temporary immersion. Most LONGWELL EC fans IP54 standard, IP55 widely available, IP67 on outdoor/coastal SKUs.

Yes. All EC fan SKUs >125 W meet EU Ecodesign Lot 6 (Reg. 327/2011 as revised) including 2026 SFP tightening. ErP documentation in technical dossier on EU shipments.

Yes. LWBE3G-residential and LWM-ERV SKUs are HVI 920 (Home Ventilating Institute) tested and certified, plus AHRI 870 where applicable.

EN 61000-6-2 (industrial immunity) and EN 61000-6-3 (residential emissions) per CE EMC Directive. Medical-grade EN 60601-1-2 option for OR/ICU/imaging. Conducted emissions class B for sensitive lab environments.

Sample: 1–3 days from stocked diameter sizes. Bulk (≤500 units): 15–30 days. OEM volume (1,000+): 6–10 weeks. ebm-papst 2026 lead time 14–22 weeks; Ziehl-Abegg 12–18 weeks.

Catalog SKU: MOQ = 1 unit. Custom OEM (private label, custom impeller, special voltage, controls): MOQ = 100–500 units. Tooling-modification programs: MOQ = 1,000–3,000 units.

Yes. OEM/ODM program covers private label, custom impeller geometry, custom motor voltage (24/48/110/230/400V), custom housing materials, custom controls firmware. First batch lead time 3–4 months including engineering.

Standard: 24 months from shipment. OEM extended 36 or 60 months on qualifying volume contracts. Warranty replacement: same-SKU shipment within 5 working days from EU/US warehouses, 15 days from China direct.

Yes. EU bonded warehouses in Rotterdam and Hamburg, US distribution from Chicago, MENA hub in Dubai. CBAM emissions disclosure for EU. INCO: FOB Shenzhen/Ningbo, EXW factory, CIF/DDP available.

Replacement impellers, motor capsules, bearing kits, electronic boards (3-phase), conformal-coated control boards, fan grilles, inlet rings stocked. Same-SKU warranty replacements ship within 5 working days from EU/US warehouses.

7-day fast track: customer submits CFM/Pa/ambient/IP via web; LONGWELL returns sized BOM in 24 hours; samples ship day 2–3; customer tests; decision day 6; PO day 7. Used by hundreds of OEMs for rapid prototyping.

As of May 2026: LONGWELL LWBE3G-355-EC ~$220–$280 FOB Shenzhen (qty 100+); ebm-papst K3G355 €380–€480 ex-works; Ziehl-Abegg RH40C €360–€450 ex-works. Final pricing depends on voltage, IP, control, qty.

(1) 35 years (since 1990), TÜV-certified production, B&K acoustic lab, CFD lab — not a trader. (2) Real cross-reference to ebm-papst / Ziehl-Abegg with dimensional drop-in. (3) Full EU regulatory dossier (CBAM, EUDR, REACH, RoHS, bonded warehouse). (4) Fortune 500 references in heat pump and BESS.

Yes. LWBE3G family dimensionally interchangeable with K3G250 through K3G900 — same mounting, inlet ring, shaft height, 0–10 V control. Drop-in replacement, no AHU rework. Cross-reference table.

Yes. LWBE3G family dimensionally interchangeable with RH28C through RH100C. ZA-control bus bridged via free MODBUS gateway from LONGWELL Engineering.

Yes. LWAE3G-R290 axial and LWBE3G-R290 plug fans validated for propane heat pumps including 75°C ambient at discharge plenum. Spark-free EC design + sealed connection housings meet IEC 60335-2-40 safety.

Leading European heat pump OEMs (DE/IT/PL/FR monobloc R290), major CN/JP/KR brands. Specific references under NDA; case studies on request.

Yes. LWAE3G IP55 axial and LWHV high-pressure plug fans for BESS thermal management — liquid-to-air heat reject, container ventilation, emergency exhaust. IP67 + UL-listed for NFPA 855. Optional ATEX for H2 vent-out.

COP = heating capacity (kW) ÷ electrical input (kW). Heat pump fan power consumes 5–10% of total input. Switching from AC to EC typically lifts heat pump COP by 0.10–0.25 (e.g., 4.30 → 4.50) at A7/W35.

PUE = total facility power ÷ IT load power. 2026 targets: hyperscale <1.15, enterprise <1.40, edge <1.60. Switching from AC to EC on CRAH/AHU typically improves PUE by 0.05–0.10.

L2A is a rear/side-door liquid-cooled heat exchanger pulling CDU loop water (28–32°C supply) and rejecting heat via finned coil with EC plug fans. Allows 30–80 kW/rack cooling without changing room AC. LWBE3G-355 and LWHV-450 are common L2A fans.

Standard: 0–10 V analog, PWM (1 kHz), Modbus RTU (RS485), Modbus TCP (Ethernet). Optional: BACnet MS/TP, CANopen, LIN. Outputs: tachometer, fault relay, runtime, motor temperature (all via Modbus register). Free LONGWELLBUS cloud gateway provides MQTT to AWS IoT, Azure IoT Hub.

Native BACnet MS/TP and BACnet/IP gateway optional. Default Modbus RTU/TCP works with all major BMS (Niagara/Tridium, Honeywell, Siemens Desigo, Schneider EcoStruxure, Johnson Metasys) via standard gateways.

Yes. EC plug fans operate in parallel with master/slave Modbus control. Topology: 1 master, N+1 slaves on RS485 bus. Failure auto-redistributes load. LONGWELLBUS cloud logs events. Used in CRAH FanGrid retrofits.

Residential SKUs (LWM-ERV, LWBE3G-residential) support Matter 1.2 over Thread/Wi-Fi, plus Zigbee, Apple HomeKit, Google Home, Alexa, Tuya. OTA firmware updates. CSA Matter-certified.

EC fans have integrated drive — no external VFD needed. Just line power + 0–10 V. AC fans (LWFC, LWM-AC) are VFD-compatible with ABB, Yaskawa, Siemens.

Yes. CBAM (Carbon Border Adjustment Mechanism) embedded emissions report per shipment, ISO 14067 product carbon footprint, EU customs documentation. EU bonded warehouses (Rotterdam, Hamburg) handle CBAM filing.

Yes. DDP available from EU bonded warehouses. Customer receives DDP-paid landed cost, no customs/VAT obligation. CBAM emissions filing by LONGWELL.