In some ways, the DIN-rail system has become a victim of its own success. As the DIN-rail mounting system is now ubiquitous for almost all electrical, networking and telecommunication equipment, there is a tendency to try and cram as much as possible onto each rail. Each component should be as thin as possible to minimize the amount of rail space required. However, some electrical equipment generates heat, for example power supplies, contactor coils or relays, so placing these units in very close proximity to each other can adversely affect the natural convection cooling air flow. As every 10°C increase in ambient temperature halves the operational lifetime, this needs to be avoided if possible.
Solutions include adding spacers between equipment to allow free air convection to cool the components, to repositioning heat-generating components so that they are not in close proximity where they could warm each other up, or, in extreme cases, adding fans to force air cool the parts. The vertical separation between rails also needs to be considered so that warm air rising from one component does not adversely affect the component placed immediately above it. Fortunately, software packages are readily available that can be used to both plan the layout of the panel or cabinet in advance and to calculate the expected thermal loading. This software is often offered free by the cabinet manufacturers. More advanced software can also automatically check if the electrical safety, construction, and technical standards, such as EN 61439, are also being complied with.
RECOM is an established power supply manufacturer that is well-known for board-mounting or chassis-mounting embedded power, but also offers competitively priced
AC/DC DIN-rail mount power supplies (Figure 2).
