A DIN rail is a metal rail of a standard type widely used for mounting
circuit breaker
A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by an overcurrent or short circuit. Its basic function is to interrupt current flow to protect equipment and to prevent the risk ...
s and industrial control equipment inside
equipment racks. These products are typically made from cold rolled carbon steel sheet with a
zinc-plated or
chromated bright surface finish. Although metallic, they are meant only for mechanical support and are not used as a
busbar
In electric power distribution, a busbar (also bus bar) is a metallic strip or bar, typically housed inside switchgear, panel boards, and busway enclosures for local high current power distribution. They are also used to connect high volt ...
to conduct electric current, though they may provide a chassis
grounding connection.
The term derives from the original specifications published by
Deutsches Institut für Normung
' (DIN; in English, the German Institute for Standardisation Registered Association) is the German national organization for standardization and is the German ISO member body. DIN is a German Registered Association ('' e.V.'') headquartered in ...
(DIN) in Germany, which have since been adopted as European (EN) and international (IEC) standards. The original concept was developed and implemented in Germany in 1928, and was elaborated into the present standards in the 1950s.
Types
There are three major types of DIN rail:
* Top hat section (TH), type O, or type Ω, with hat-shaped cross section.
* C section
* G section
Top hat rail IEC/EN 60715
![DIN-rail-dimensions](https://upload.wikimedia.org/wikipedia/commons/5/51/DIN-rail-dimensions.svg)
This 35 mm wide rail is widely used to mount
circuit breaker
A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by an overcurrent or short circuit. Its basic function is to interrupt current flow to protect equipment and to prevent the risk ...
s,
relay
A relay
Electromechanical relay schematic showing a control coil, four pairs of normally open and one pair of normally closed contacts
An automotive-style miniature relay with the dust cover taken off
A relay is an electrically operated switch ...
s,
programmable logic controller
A programmable logic controller (PLC) or programmable controller is an industrial computer that has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines, machines, robotic devices, or any activity tha ...
s,
motor controller
A motor controller is a device or group of devices that can coordinate in a predetermined manner the performance of an electric motor. A motor controller might include a manual or automatic means for starting and stopping the motor, selecting forw ...
s, and other electrical equipment. The EN 60715 standard specifies both a 7.5 mm (shown above) and a 15 mm deep version, which are officially designated
* top hat rail IEC/EN 60715 – 35 × 7.5
* top hat rail IEC/EN 60715 – 35 × 15
Some manufacturers catalogues also use the terms: Top hat section / TH / TH35 (for 35mm wide) / Type O / Type Omega (Ω).
The rail is known as the TS35 rail in the USA.
Module width
The width of devices that are mounted on a 35 mm "top hat" DIN rail generally use "modules" as a width unit, one module being 18 mm wide. For example, a small device (e.g. a circuit breaker) may have a width of 1 module (18 mm wide), while a larger device may have a width of 4 modules (4 * 18 = 72 mm wide). Equipment enclosures also follow these module widths, so an enclosure with a DIN rail may have space for 20 modules, for example. Not all devices follow these module widths.
Module widths are usually abbreviated as "M" (e.g. 4M = 4 modules) . Some manufacturers (including Mean Well) use "SU" (likely stands for "standard unit", e.g. 4SU = 4 modules) .
C section
These rails are symmetrical within the tolerances given. There are four popular C section rails, C20, C30, C40 and C50. The number suffix corresponds to the overall vertical height of the rail.
G section
G-type rail (according to EN 50035, BS 5825, DIN 46277-1).
::
![G-Schiene EN 50035 (G32)](https://upload.wikimedia.org/wikipedia/commons/3/34/G-Schiene_EN_50035_%28G32%29.svg)
G rail is generally used to hold heavier, higher-power components. It is mounted with the deeper side at the bottom, and equipment is hooked over the lip, then rotated until it clips into the shallower side.
Others
In addition to the popular 35 mm × 7.5 mm top-hat rail (EN 50022, BS 5584, DIN 46277-3), several less widely used types of mounting rails have also been standardized:
* Miniature top-hat rail, 15 mm × 5.5 mm (EN 50045, BS 6273, DIN 46277-2);
* 75 mm wide top-hat rail (EN 50023, BS 5585);
Related equipment
*
European Standard
European Standards (abbreviated EN, from the German name ("European Norm")) are technical standards which have been ratified by one of the three European standards organizations: European Committee for Standardization (CEN), European Committee for ...
EN 50022: Specification for low voltage switchgear and control-gear for industrial use. Mounting rails. Top hat rails 35 mm wide for snap-on mounting of equipment. (formerly:
German Standard
German(s) may refer to:
* Germany (of or related to)
** Germania (historical use)
* Germans, citizens of Germany, people of German ancestry, or native speakers of the German language
** For citizens of Germany, see also German nationality law
**Ge ...
DIN 46277,
British Standard
British Standards (BS) are the standards produced by the BSI Group which is incorporated under a royal charter and which is formally designated as the national standards body (NSB) for the UK. The BSI Group produces British Standards under the a ...
BS 5584)
*
IEC
The International Electrotechnical Commission (IEC; in French: ''Commission électrotechnique internationale'') is an international standards organization that prepares and publishes international standards for all electrical, electronic and r ...
International Standard 60715: Dimensions of low-voltage switchgear and control-gear. Standardized mounting on rails for mechanical support of electrical devices in switchgear and control-gear installations.
*
Australian Standard
Standards Australia is a standards organisation established in 1922 and is recognised through a Memorandum of Understanding (MoU) with the Australian government as the primary non-government standards development body in Australia. It is a c ...
AS 2756.1997: Low-voltage switchgear and controlgear - Mounting rails for mechanical support of electrical equipment.
See also
*
Printed circuit board
A printed circuit board (PCB; also printed wiring board or PWB) is a medium used in Electrical engineering, electrical and electronic engineering to connect electronic components to one another in a controlled manner. It takes the form of a L ...
References
External links
*
{{Deutsches Institut für Normung
EN standards
Mechanical standards
Rail
Rail or rails may refer to:
Rail transport
*Rail transport and related matters
*Rail (rail transport) or railway lines, the running surface of a railway
Arts and media Film
* ''Rails'' (film), a 1929 Italian film by Mario Camerini
* ''Rail'' ( ...