AC Axial Fan for Industrial Control Panels: 112 CFM Case Study

What the panel builder needed

A European OEM building automation control panels wanted a cheaper alternative to their German fan supplier. They needed a true drop-in. Namely a 120 by 120 by 38mm AC axial fan needing no change to the existing chassis.

Those panels hold PLCs, contactors and drives, all making heat inside a sealed box. Meanwhile the enquiry began modestly, as a request for a standard spec sheet.

• 220 VAC at 50 or 60Hz, since that bus already exists.
• At least 95 CFM of free-air delivery, to hold safe internal temperatures.
• No more than 45 dBA, since control rooms carry workplace noise limits.
• A minimum L10 life of 50,000 hours at a 40C ambient.
• CE marking as mandatory, with UL component recognition strongly preferred for North American exports.
• Lastly, an operating range of -10C to +65C.

The L10 line is what shapes the engineering. Fifty thousand hours is nearly six years of running non-stop. Consequently that figure picks the bearing before anything else does.

Specifying the AC axial fan, twice

A 120 by 38mm AC axial fan points straight at our LWAA12038SH series, built around a 220 VAC shaded-pole motor for exactly this kind of cabinet cooling.

Why not EC

We weighed a more efficient EC variant, then rejected it. Their system runs on a direct 220 VAC bus, so an EC fan would need an AC/DC supply added. That brings cost, complexity and one more thing to fail inside a panel already crowded.

The decision that mattered: bearings

Here the customer builds two tiers of panel, a standard line and a high-reliability line. So instead of picking one bearing, we offered two versions of the same fan.

• LWAA12038SH-35-00 uses a sleeve bearing, which keeps the price competitive for standard panels.
• LWAA12038SH-36-00 uses a ball bearing system, giving longer life and better durability for the high-reliability tier.

Consequently the customer qualifies one air design and one mechanical shape, yet still serves two market tiers with two SKUs. That costs far less than qualifying two different fans.

Materials and protection

The frame is die-cast aluminum alloy, which survives rough handling and helps shed heat. Meanwhile the impeller is UL94-V0 rated PBT plastic, which matters in a panel full of live terminals.

Meanwhile the motor is impedance protected. If the rotor locks, winding impedance limits the current, so the fan cannot overheat. It holds that safely for at least 72 hours, which UL 507 requires rather than merely suggests.

Technical Specifications

Two model numbers appear below, -35 and -36. Read the bearing row to see what separates these two AC axial fan variants, since almost nothing else does.

Technical Documentation

The following documents were approved and provided to the customer, enabling their engineering team to complete the component qualification process.

LWAA12038SH-35-00 Specification (Sleeve Bearing)
Here the datasheet provides complete performance data, mechanical drawings, and electrical specifications for the LWAA12038SH-35-00 model, essential for design engineers integrating the sleeve bearing version.

LWAA12038SH-36-00 Specification (Ball Bearing)
This document details the LWAA12038SH-36-00 model, identical in performance but featuring a ball bearing for extended life, intended for procurement managers specifying higher-reliability components.

The standard 120mm frame and 7-blade impeller design of the LWAA12038SH series, engineered for consistent performance.

Why the OEM changed supplier

Beyond the specification itself, four things carried this.

• Cost reduction with no re-engineering. This AC axial fan is a one-for-one drop-in, meeting every critical specification without a chassis change. The saving comes from not redesigning anything, which is the cheapest kind of saving there is.
• Two bearings, one qualification. Supplying fully documented specifications for both the -35 and -36 models let the customer keep separate SKUs for standard and premium panels while qualifying a single design.
• One fan for both continents. The series holds CE and UL component recognition together, so the same part goes into panels bound for the EU and for North America. That removes a second supply chain entirely.
• Curves engineers can use. P-Q and acoustic curves come from testing to AMCA 210/211 and ISO 5801 methods. In short, that is what lets a technical team commit without re-measuring.

Browse our AC axial fan range, or the compact cooling fan section. Electrical safety standards come from UL Solutions in UL 507.

Questions panel builders ask

Can I use a VFD to control the speed?

No. This AC axial fan uses a shaded-pole induction motor, which a variable frequency drive will overheat and eventually destroy. Where you need variable speed, take a fan from our SmartEC axial series instead, since those carry a 0-10V and PWM interface built in.

What is the lead time on 1,000 units?

A standard make-to-order run of 1,000 units takes 15 to 25 days from purchase order confirmation to ex-works Ningbo. Smaller quantities are often available from regional stock with a 1 to 5 day lead time.

Does it have locked rotor protection?

Yes, through impedance protection. If the impeller stalls, the winding impedance limits current draw so the motor cannot overheat. The design complies with UL 507 and protects against fire for at least 72 hours under a locked rotor fault at rated 220 VAC.

Which bearing should I choose?

It depends on ambient temperature and running hours, rather than on price alone. Sleeve bearings are quieter and cheaper, yet their life falls sharply as temperature climbs. Ball bearings hold their rating in a warm panel. Consequently they suit the high-reliability tier and the 50,000-hour figure.