A DIN Rail is a metal rail of with standard size of 35 mm wide. (A)

It's commonly used on installation and assembly of electrical devices or controllers for home or business use.
Besides the typical DIN rail 35 mm x 7.5 mm, can also be found in other measures as:

- Mini DIN Rail, size 15 mm x 5.5 mm (B)
- DIN Rail, size 35 mm x 15 mm (C)
- G section, size 32 mm x 15 mm x 8mm (D)

These rails are designed for installations with a method of simple, fast and configurable fixing. Ideal for installation in electrical distribution points, distribution of telephone wiring, alarms, digital electric programmers, keystone adapter, attenuators and any other compatible device.

VDC would be the abbreviation for Volt Direct Current which translated would volts direct current. The idea of ??this type is unidirectional current to the load. Direct current is normally produced by batteries, thermocouples, solar cells and a dynamo electric machine type. The direct current can flow in conductors such as wires, but may also flow through semiconductors, insulators ... In the image: 1 - current per pulse 2 - Direct Current (DC) 3 - Alternating Current (AC) 4 - Variable Current

The DIN is a standard that was developed by the "Deutsches Institut für Normung" (one might call the national standards organization in Germany). The DIN is facing many sectors, but we have tried to focus on the DIN-oriented electronics and computing. In the case of Enclosures means qualifying under the German legislation on racks and is standardized to DIN 41494-7.

It is a special multi point communication for industrial machinery by its format adapted to long distance and heavy machinery. The connector is used to connect the DB9 serial port or popularly called. One characteristic is that it is able to greatly reduce the noise so that the distance is much greater.