Fan-and-filter units are a small, often unnoticed detail in enclosures. If the filter media they contain must be replaced because of contamination, plant operators often turn to filters that are as inexpensive as possible. But beware! The lowest procurement costs are not always the lowest overall costs. Moreover, selecting the wrong filter can even endanger the entire plant’s operation. Now, the new pleated filters for the Rittal TopTherm fan-and-filter units give operators peace of mind. Consequently, the enclosure does not become a dust collector in the first place; the new pleated filters ensure that the protection category is retained and can also reduce energy consumption and operating costs.
Fan-and-filter units filter the cooler ambient air before it enters the enclosure, simultaneously allowing the heated internal air to escape through an outlet filter. It is im-portant that the fan-and-filter unit does not reduce the enclosure's protection category while the highest possible volumetric air flow is achieved at the same time. This way, it dissipates the heat load of the built-in electronic components in the enclosure and prevents the formation of hotspots.
The drawbacks with the filter medium
Fan-and-filter units must be designed to prevent dust and sprayed water from entering. The reliability of the gasket, the shape of the lamina, and the choice of filter material all play a vital role. However, the devil is in the details, especially when it comes to the latter. If the filter for instance is too tight, not enough air will be able to pass through; if it is too porous, excessive amounts of dust or even water can enter the enclosure and damage components. What’s more: If foreign material is used for the filter medium, for example, after it has been individu-ally cut from a roll, the protection category will no longer be guaranteed.
Everything is balanced out
Rittal has managed to balance these demands with its new pleated filters. Not only is the desired IP54 protection category guaranteed, but enclosures are also reliably protected against damaging levels of dust and dirt particles: The pleated filters’ higher separation efficiency, namely more than half as much again than conventional filter media, means that the components in the enclosure exhibit a lower failure rate. In addition, small dust particles (0.3–1 µm) are separated much more efficiently, while the air throughput is increased at the same time.
Air throughput is efficiently increased
Thanks to the pleats, the filters have a six times larger surface area that is more air permeable than a conven-tional chopped-fibre filters. This allows up to 40 per cent more air to pass through. Electricity costs can also be significantly reduced thanks to this higher air throughput. This means a huge 22 percent fewer operating hours in terms of numbers. This not only saves energy but also slashes service and operating costs. These savings also result from the longer fan life, achieved in turn through the shorter running times, allowing maintenance intervals to be extended by a factor of two to three. Thanks to this improved function, a smaller fan could even be used while still delivering full performance.
- Use our efficiency calculator here to discover how much you can save for your own installation.