DIN rail

{{Short description|International standard for mounting equipment}} {{multiple image | align = right | direction = vertical | width = 200 | image1 = Din rail.jpg | caption1 = A front view of a populated 35 mm DIN rail | image2 = DIN rail rear view.JPG | caption2 = Rear view. Note the release loops at the top of the mounted devices which unclip them.}}

A '''DIN rail''' is a metal rail of a standard type widely used for mounting [[circuit breaker]]s and industrial control equipment inside [[Enclosure (electrical)|equipment racks]]. These products are typically made from cold rolled carbon steel sheet with a [[Galvanization|zinc-plated]] or [[Chromate conversion coating|chromated]] bright surface finish. Although metallic, they are meant only for mechanical support and are not used as a [[busbar]] to conduct electric current, though they may provide a chassis [[Ground (electricity)|grounding]] connection.

The term derives from the original specifications published by [[Deutsches Institut für Normung]] (DIN) in Germany, which have since been adopted as European (EN) and international (IEC) standards.<ref>{{cite book|last1=Simpson|first1=Robert|title=Lighting Control: Technology and Applications|date=2003|publisher=Focal Press/Elsevier|location=Oxford UK|isbn=0-240-51566-8}}</ref> The original concept was developed and implemented in Germany in 1928, and was elaborated into the present standards in the 1950s.<ref>{{cite web|url=https://site.ieee.org/npec-sc2/files/2017/06/SC-2Mgt08-2_Att9-WP_DIN-Rail.pdf|title=DIN-Rail in the Electrical Control Cabinet and Junction Box|author=Arnold Offner|website=[[IEEE]] Power and Engineering Society|author2=Phoenix Contact|date=November 12, 2008|access-date=May 31, 2018}}</ref>

==Types== There are three major types of DIN rail:<ref>{{cite book|last1=Tickoo|first1=Sham|title=AutoCAD Electrical 2010 for Engineers|date=2010|publisher=Dorling Kindersley|location=India|isbn=978-81-317-3213-7|pages=8–46}}</ref> * Top hat section (TH), type O, or type Ω, with hat-shaped cross section. * C section * G section

===Top hat rail IEC/EN 60715=== [[File:DIN-rail-dimensions.svg|120px]]

This 35 mm wide rail is widely used to mount [[circuit breaker]]s, [[relay]]s, [[programmable logic controller]]s, [[motor controller]]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).{{citation needed|date=January 2012}}

The rail is known as the TS35 rail in the US.{{citation needed|date=February 2024}}

====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 {{nobr|1=(4 × 18 mm = 72 mm).}} 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. {{citation needed|date=April 2020}}

Module widths are usually abbreviated as "M" (e.g. 4M = 4 modules) {{citation needed|date=April 2020}}. Some manufacturers (including Mean Well) use "SU" (likely stands for "standard unit", e.g. 4SU = 4 modules) {{citation needed|date=April 2020}}.

===C section=== These rails are symmetrical within the tolerances given and referenced by the standard EN 50024 (abrogated). There are four popular C section rails, C20, C30, C40 and C50. The number suffix corresponds to the overall vertical height of the rail.

[[File:C-section-rail-C30.svg|350px]]

===G section=== [[File:G-type-Din-rail.jpg|thumb|Cross section view of a G-type DIN rail, with electrical equipment mounted on it]] G-type rail (according to EN 50035 (abrogated), BS 5825, DIN 46277-1). :: [[File:G-Schiene EN 50035 (G32).svg|300px]] 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]] 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]] DIN 46277, [[British Standard]] BS 5584) * [[International Electrotechnical Commission|IEC]] [[List of IEC standards|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. * [[Standards Australia|Australian Standard]] AS 2756.1997: Low-voltage switchgear and controlgear - Mounting rails for mechanical support of electrical equipment.

==See also== * [[Printed circuit board]]

==References== {{Reflist}}

==External links== * {{Commons category-inline}}

[[Category:EN standards]] [[Category:Mechanical standards]] [[Category:Deutsches Institut für Normung|Rail]]