Author: longwell

ec fans in hvac ventilation
By longwell / May 13, 2026 / Technical Articles

EC Fans in HVAC Ventilation: Driving the Future of Energy-Efficient Airflow

In today’s fast developing pace, efficiency is paramount in every indu...

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White powder coated weather cowl for an exterior duct termination
By longwell / May 13, 2026 / Engineering Case Studies

Why Paint Was the Wrong Answer for an Outdoor Cowl

The requirement was purely cosmetic. The engineering was entirely abou...

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EC fan replacing a unit limited by shaded-pole motor speed control
By longwell / May 13, 2026 / Engineering Case Studies

You Cannot Put a VFD on a Shaded-Pole Motor

The obvious way to add speed control to an existing AC fan does not wo...

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Universal voltage fan, 172mm EC axial, rated IP55
By longwell / May 12, 2026 / Engineering Case Studies

One Fan SKU for Every Market: The 100-240V Argument

They asked for an EC replacement. What they got that they had not aske...

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A 250mm DC axial fan showing fan protection features for outdoor use
By longwell / May 12, 2026 / Engineering Case Studies

Three Protections That Matter in an Unattended Cabinet

Nobody visits a roadside telecom cabinet to check a fan. Its fan prote...

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High-temperature AC motor with Class H insulation for a heater
By longwell / May 12, 2026 / Engineering Case Studies

High-Temperature AC Motor for a Commercial Heater: Class H

Three watts of output, and almost all the engineering went into surviv...

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Cross-flow fan rebuilt for a fan speed increase in the same housing
By longwell / May 12, 2026 / Engineering Case Studies

More Speed Buys Airflow and Spends Bearing Life

Raising speed is the fastest way to more airflow in a fixed housing. I...

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Fan coil unit selected despite a capacity mismatch with the brief
By longwell / May 11, 2026 / Engineering Case Studies

The Unit They Chose Was Half the Capacity They Asked For

They asked for 3 to 4 kW, then picked a 1.9 kW unit from the catalog. ...

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longwell--project-image-05-jpg
By longwell / May 11, 2026 / Engineering Case Studies

The Regulation Chose the Motor Before We Did

We usually explain why EC beat AC on the merits. In this order, the la...

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Ignition electrode specification drawing with ceramic insulator
By longwell / May 11, 2026 / Engineering Case Studies

A Photograph and a Voltage: Building a Drawing From Nothing

The brief was an image and two figures. Everything else had to be deri...

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