 | This article needs additional citations for verification .(June 2017) |
Tri-rated cable is a high temperature, flame retardant electrical wire designed for use inside electrical equipment.
Tri-rated cable meets the requirements of three different international standards: BS 6231, UL 758, and CSA 22.2. [1] Combining three standards in one product makes tri-rated cable suitable for use in equipment that is required to meet both North American and British wiring regulations. [2]
Tri-rated cables are constructed with a flexible stranded copper conductor (Class 5 according to IEC 60228), and insulation of heat resistant PVC. Tri-rated cable is manufactured in a variety of insulation colours, including brown, orange, yellow, pink, and dark blue. [3]
Tri-rated cable is designed for use in switch, control, relay and instrumentation panels of power circuits, and as internal connectors in rectifier equipment, motor starters and motor controllers. [2]
BS 6231 is a British Standard, last revised in 2006 by the BSI Group. [4] This standard specifies the performance and construction requirements of electrical cables that are single core, non-sheathed, PVC-insulated and rated 600/1000 V. Wire meeting the requirements of type CK of this standard is used as tri-rated wire.[ citation needed ] This standard specifies a nominal insulation thickness of 0.8mm for wire sizes 0.5mm2 to 6mm2. Larger wires sizes are required to have thicker insulation.
Wire that is approved to BS 6231 might not carry the UL and CSA ratings, if, for example, the wire is not suitable for use at the higher 105 °C temperature that is specified for those ratings. In that case, the wire is not tri-rated.
According to UL 758, the maximum operating temperature of tri-rated cable is 105 °C. British Standard BS 6231 requires only a maximum operating temperature of 90 °C for continuous use. UL and CSA give tri-rated cable a voltage rating of 600 V, while it is rated at 1000 V in the BS 6231 standard.
UL 758 is a standard maintained by UL LLC, principally for the U.S. market. This standard covers "Appliance Wiring Material" ("AWM"), including single-insulated conductors and individual insulated conductors. [5] Wire meeting the requirements of UL Style 1015 is considered tri-rated wire.[ citation needed ] UL Style 1015 specifies wire sized from 28 to 9 AWG, with a maximum temperature of 105 °C, a voltage rating of 600 V, and PVC insulation with a thickness of 1⁄32 inch (0.8 mm). [6]
CSA 22.2 Part 210-11 covers "Appliance Wiring Material". [7] CSA 22.2 Part 127-18 covers "Equipment and lead wires". [8]
IEC 60320 Appliance couplers for household and similar general purposes is a set of standards from the International Electrotechnical Commission (IEC) specifying non-locking connectors for connecting power supply cords to electrical appliances of voltage not exceeding 250 V (a.c.) and rated current not exceeding 16 A. Different types of connector are specified for different combinations of current, temperature and earthing requirements. Unlike IEC 60309 connectors, they are not coded for voltage; users must ensure that the voltage rating of the equipment is compatible with the mains supply. The standard uses the term coupler to encompass connectors on power cords and power inlets and outlets built into appliances.
A power cord, line cord, or mains cable is an electrical cable that temporarily connects an appliance to the mains electricity supply via a wall socket or extension cord. The terms are generally used for cables using a power plug to connect to a single-phase alternating current power source at the local line voltage. The terms power cable, mains lead, flex or kettle lead are also used. A lamp cord is a light-weight, ungrounded, single-insulated two-wire cord used for small loads such as a table or floor lamp.
Electrical wiring in North America follows the regulations and standards applicable at the installation location. It is also designed to provide proper function, and is also influenced by history and traditions of the location installation.
The National Electrical Code (NEC), or NFPA 70, is a regionally adoptable standard for the safe installation of electrical wiring and equipment in the United States. It is part of the National Fire Code series published by the National Fire Protection Association (NFPA), a private trade association. Despite the use of the term "national," it is not a federal law. It is typically adopted by states and municipalities in an effort to standardize their enforcement of safe electrical practices. In some cases, the NEC is amended, altered and may even be rejected in lieu of regional regulations as voted on by local governing bodies.
Appliance classes specify measures to prevent dangerous contact voltages on unenergized parts, such as the metallic casing, of an electronic device. In the electrical appliance manufacturing industry, the following appliance classes are defined in IEC 61140 and used to differentiate between the protective-earth connection requirements of devices.
In electricity supply design, a ring circuit is an electrical wiring technique in which sockets and the distribution point are connected in a ring. It is contrasted with the usual radial circuit, in which sockets and the distribution point are connected in a line with the distribution point at one end.
Electrical wiring is an electrical installation of cabling and associated devices such as switches, distribution boards, sockets, and light fittings in a structure.
Electrical wiring in the United Kingdom is commonly understood to be an electrical installation for operation by end users within domestic, commercial, industrial, and other buildings, and also in special installations and locations, such as marinas or caravan parks. It does not normally cover the transmission or distribution of electricity to them.
A power cable is an electrical cable, an assembly of one or more electrical conductors, usually held together with an overall sheath. The assembly is used for transmission of electrical power. Power cables may be installed as permanent wiring within buildings, buried in the ground, run overhead, or exposed. Power cables that are bundled inside thermoplastic sheathing and that are intended to be run inside a building are known as NM-B.
Ampacity is a portmanteau for ampere capacity defined by United States National Electrical Codes. Ampacity is defined as the maximum current, in amperes, that a conductor can carry continuously under the conditions of use without exceeding its temperature rating.
Heat-shrink tubing is a shrinkable plastic tube used to insulate wires, providing abrasion resistance and environmental protection for stranded and solid wire conductors, connections, joints and terminals in electrical wiring. It can also be used to repair the insulation on wires or to bundle them together, to protect wires or small parts from minor abrasion, and to create cable entry seals, offering environmental sealing protection. Heat-shrink tubing is ordinarily made of polyolefin, which shrinks radially when heated, to between one-half and one-sixth of its diameter.
Mineral-insulated copper-clad cable is a variety of electrical cable made from copper conductors inside a copper sheath, insulated by inorganic magnesium oxide powder. The name is often abbreviated to MICC or MI cable, and colloquially known as pyro. A similar product sheathed with metals other than copper is called mineral-insulated metal-sheathed (MIMS) cable.
A thermoplastic-sheathed cable (TPS) consists of a toughened outer sheath of polyvinyl chloride (PVC) thermoplastic, covering one or more individual annealed copper conductors, themselves insulated with PVC. This type of wiring is commonly used for residential and light commercial construction in many countries. The flat version of the cable, with two insulated conductors and an uninsulated earth conductor, is referred to as twin and earth. In mainland Europe, a round equivalent is more common.
A portable cord is a cable with multiple conductors used for temporary electrical power connections requiring flexibility. The cord can be employed in a range of applications, such as operating motors in small and large tools, equipment, power extensions, home appliances, and machinery.
In electrical safety testing, portable appliance testing is a process in the United Kingdom, Ireland, New Zealand and Australia by which electrical appliances are routinely checked for safety. The formal term for the process is "in-service inspection & testing of electrical equipment". Testing involves a visual inspection of the equipment and that any flexible power cables are in good condition, and also where required, verification of earthing (grounding) continuity, and a test of the soundness of insulation between the current carrying parts, and any exposed metal that may be touched. The formal limits for pass/fail of these electrical tests vary somewhat depending on the category of equipment being tested.
Twin and earth cable is a colloquial name in the UK, Australia, New Zealand and other countries for a type of flat sheathed fixed mains electricity cable, containing two insulated current-carrying conductors and an Earth connector. In Australia and New Zealand this type of cable is referred to as 'Flat TPS', as well as "Twin and Earth" or "Twin with Earth".
In electrical power distribution, armoured cable usually means steel wire armoured cable (SWA) which is a hard-wearing power cable designed for the supply of mains electricity. It is one of a number of armoured electrical cables – which include 11 kV Cable and 33 kV Cable – and is found in underground systems, power networks and cable ducting.
Copper has been used in electrical wiring since the invention of the electromagnet and the telegraph in the 1820s. The invention of the telephone in 1876 created further demand for copper wire as an electrical conductor.
Plugs and sockets for electrical appliances not hardwired to mains electricity originated in the United Kingdom in the 1870s and were initially two-pin designs. These were usually sold as a mating pair, but gradually de facto and then official standards arose to enable the interchange of compatible devices. British standards have proliferated throughout large parts of the former British Empire.