DC fans have distinct advantages compared with AC fans: 3-4 x lower power input, lighter in weight, wider range, easy to control, simple function monitoring as well as higher life expectancy due to lower inherent heat.
In many cases, however, only mains voltage is available. With a simple yet inexpensive ballast for standard DC fans, SEPA Europe GmbH now offers the solution to this problem. With the LMV12W12, a special miniature switched-mode power supply individual or several DC fans can be operated simultaneously up to a total power input of 12 Watt with an alternating voltage of 176 to 264 VAC. The DC output is both idling and short-circuit proof. The entire efficiency coefficient is only marginally lower than that of the DC fan alone. The price of fans plus power unit is equivalent to that of a high-quality AC fan. For supplying several DC fans, this solution is in fact cheaper than with AC fans.