Energy-efficient cooling system for electrical cabinets

Focus on reducing carbon emissions and rising energy costs have prompted manufacturers of air-conditioning systems - for use in electrical cabinets - to look for solutions to reduce energy consumption. Manufacturers currently optimise refrigerant circuits and integrate low-power fans to cut electricity costs and consumption, and make the device more environmentally friendly. These efforts are no doubt geared towards the future, especially in large manufacturing facilities with a variety of air-conditioned cabinets. But the drawback is that these solutions are still based on a regulating method which merely switches the compressor on and off. So, these systems either run in full power or not at all. In addition, the compressor always needs a defined standing time between its operation phases before it can start again. The consequences are severe temperature fluctuations and moisture build-up in the cabinet, as well as high stress for the installed components and a heavy load on the air conditioners which can quickly lead to total failure.

Seifert mtm Systems, a German-headquartered developer of temperature control management systems for industrial control cabinets, is consequently addressing the problem and, together with a major compressor manufacturer, working on a speed-controlled system that finally does away with these disadvantages. With just three ecool devices and a cooling capacity ranging from 250 to 3500 W, all industrial sizes and requirements - from compact to large control cabinets - are covered. The compact compressor, which sets its speed to provide the required cooling performance, only requires the power input necessary for the actual cooling. With the second generation of the ecool air conditioners, a uniform temperature level in the cabinet of up to ±0.2 K is obtained for slow changes, which stresses the electronic components and the air conditioner significantly less. This results in higher safety and longer life. In addition, the formation of condensation in the cabinet is minimised.

Using adjustable compressors increases the coefficient of performance (COP) significantly - the current ecool devices which operate in this way reach a COP of up to 2.5 at L35/L35, while conventional systems achieve only 2.1. As an example, these numbers translate into the following results for the 2000 W class: with only 1000 W of electrical power, a cooling performance of 2500 W can be achieved, whereas other known devices achieve only 2100 W. This means an additional yearly saving average of up to 20% compared to other energy-saving cooling units available at present. The flexibility of the new Seifert Ecool devices features another advantage - with other inflexible systems, unnecessary costs and efforts go into installing larger air conditioners if cabinets are upgraded with additional components. This is not needed for an ecool system, since it will adjust to the new set-up. Particularly for outdoor applications, the ecool devices can be combined with fresh and filtered environmental air for component cooling. This would mean a bonus reduction of power consumption. In case of power failure, the devices can also be operated by DC battery. Therefore, consistent and safe air conditioning is ensured at all times.

The new, sturdy Seifert high-performance air conditioners are integrated into one compact stylish housing made of sheet metal that can be custom painted in RAL colours. For special applications, Seifert also manufactures stainless steel housings. Customers whose requirements are very specific and who might not find their suitable solution in the standard product range can rely on Seifert’s engineering department to design tailor-made application systems within international quality guidelines. Apart from saving power, Seifert’s air conditioners are also environmentally friendly, avoiding to a large extent the use of plastics and operating using the refrigerant R134a. They can also be equipped with a washable permanent metal filter for use in high particle-carrying environments. Incurring no significantly higher costs than conventional air conditioners, the strong second-generation ecool units are a sure investment, profitable even within a few months of operation, according to Seifert mtm Systems.