In DIN-rail mounting, a clip attaches hardware to a standard DIN rail, which is usually fastened to an enclosure or a rack. Of the three different DIN-rail standards, the 35 mm wide configuration is the most prevalent. This type of mounting is commonly used in industrial control applications. It is convenient because many manufacturers provide devices including Ethernet switches and power supplies that are compatible with this standardized footprint. DIN-rail mounting is not as sturdy as panel mounting, but it is easier to configure because it requires fewer holes and screws. You can use it to mount hardware in different configurations as your application needs change simply by clipping the device into or out of place. DIN-rail mounting saves time when you need to replace a component because you do not have to redesign a mounting panel and drill additional holes for new hardware.
Figure 2. DIN-Rail Mounting Configuration in a Lab Setup