Fans AA9251MS-AWSize 110V 0.15A 90 x 90 x 25mm case fan

Compact 90 mm AC axial fan

This 90 x 90 x 25 mm axial fan runs on 110–120 V mains power and draws 0.15 A. It is built for industrial and commercial equipment such as medical devices, rail vehicles, drives, hotel systems, cleaning machines, electronic enclosures, new-energy vehicles and supermarket units. The fan is not intended for standard PC case cooling because it requires AC mains voltage instead of a 12 V DC header. Buyers who need a low-voltage PWM or DC fan for a motherboard should look elsewhere.

Direct wire installation

The unit has no Molex, 3-pin or 4-pin connector; the leads must be wired into an AC circuit with proper insulation and strain relief. Installation therefore requires basic electrical wiring skill and adherence to local mains-voltage safety codes. A common mistake is connecting the fan to a PC fan header, which will damage the header and leave the fan inoperative. Another issue is mounting the 25 mm thick frame in a chassis that only accepts 15 mm or 20 mm fans.

110–120 V AC operation limits

Because the fan operates directly from 110–120 V AC, it cannot be speed-controlled by a motherboard PWM signal or a typical DC fan controller. Speed is fixed by line frequency and voltage, so airflow and noise stay constant. The fan also lacks a tachometer output, so the host system cannot monitor its rotation. These constraints make it unsuitable for builds that rely on software fan curves or thermal feedback loops.