News archive

PAPST Introduces Industry's First Reversible Fans - Now you can blow or suck at will!

The latest innovation in cooling fans from PAPST is the reversible fan designed to allow the direction of airflow in enclosures or cooling equipment cabinets to be instantly reversed whenever required. Initially available as an option on PAPST's high performance 6200 Series of 6-inch axial fans and DV6200 diagonal fans, the reversible option will be introduced on other PAPST fans to meet demand.

With the new fans, the direction of rotation is controlled simply applying a DC voltage to an additional wire on the fan. Without the voltage, the fan blows air in its normal direction, but as soon as a DC supply voltage is applied, the fan stops and reverses with minimum loss of efficiency. This allows the airflow direction to be controlled automatically from an external sensor or switch circuit.

All the control electronics including electronic commutation are housed in the fan body so no external circuitry is required. The 6200 Series fans with reversing option features a high airflow of 241 Cu.ft/min in free air. Reversing is also available as an option on the newly announced DV6200 'diagonal' fan whose unique design effectively combines the advantages of both axial fans with their high airflow in free air with the high pressure of a radial fan. This allows it to maintain high airflow even when the enclosure exerts a considerable back-pressure, unlike conventional axial fans whose airflow reduces as back pressure increases.

Why reversing fans? Equipment cooling fans are normally designed to blow air in or out in one direction only. However, in many applications, it is useful to be able to reverse the airflow when required.

In more conventional electronic equipment, reversible fans give equipment designers the option of reversing airflow if hot-spots or condensation develop. If hotspots develop, it may be preferable to evacuate the hot air more directly by reversing airflow so heated air is not simply blown over other parts of the equipment, causing even more overheating – or cold or humid external air is not blown over warm circuitry causing condensation.

PAPST has been developing fans, thermal management systems and motors for over 50 years including the development of the first electronically commutated fans and small motors now widely used thoughout the industry. Today, the company provides the industry's widest range of fans and thermal management systems with innovative developments such as SINTEC sintered bearings, reversible fans, intelligent variable speed fans and complete thermal management systems for control and monitoring multiple fans in large racks and assemblies.

As the market leader in equipment cooling fans, PAPST produces over 80,000 products per day. The company was founded in 1942 and today has a worldwide turnover of some £105million employing over 1,000 people in its manufacturing operations alone. PAPST's UK operation is located in a modern facility in Andover which provides assembly, sales and technical support services including the use of sophisticated design and test facilities which customers can use to test fan performance, noise and so on under a wide variety of operating conditions.