AXIAL FLOW DRAFT FAN

The WK series is a compact axial fan for panel cooling, small condensers, refrigeration cabinets and electrical enclosures - the places where a small moving-air component is needed rather than a full fan assembly.

Nine frame sizes run from 80 x 80 x 25 mm up to 172 x 150 x 51 mm, so the range covers the standard cut-outs used on control panels and small equipment. Voltages are 115 V or 220 V at 50/60 Hz, power is 11 W to 37 W, airflow 17 to 160 CFM and noise 29 to 53 dB(A). The model code combines frame size, an A1 or A2 variant, the H marking, the bearing type (S for sleeve, B for ball) and the L suffix.

The bearing choice is the decision that matters most. Sleeve bearings are quieter and cheaper, and they are fine for equipment that runs intermittently in a clean, upright position. Ball bearings cost more but tolerate higher temperature, longer duty and, critically, any mounting angle - a sleeve-bearing fan mounted horizontally or upside down wears out quickly because the oil cannot stay at the bearing.

Weights run from 240 g to 950 g. All versions are supplied with lead wires and can be fitted with a finger guard or filter where the fan is accessible.

Selection is by the required airflow at the actual system resistance and by the space available - a fan rated 100 CFM free air will deliver far less through a filter and a louvre. Check the noise figure against the application: in a cold room the fan noise is masked, but in a shop cabinet it is not, and a 50 dB fan at close range is intrusive.