This part of GB/T 11918 specifies structures, mechanical properties, electrical performance and other technical requirements of plugs, socket-outlets and couplers for industrial purposes.
This part applies to plugs and socket-outlets, cable couplers and appliance couplers, with a rated operating voltage not exceeding 1 000 V d.c. or a.c. and 500 Hz a.c., and a rated current not exceeding 800 A, primarily intended for industrial use, either indoors or outdoors.
These accessories are intended to be installed by instructed persons (GB/T 2900.73-2008, Definition 195-04-02) or skilled persons (GB/T 2900.73-2008, Definition 195-04-01) only.
The list of preferred ratings is not intended to exclude other ratings.
This part applies to plugs and socket-outlets, cable couplers and appliance couplers, hereinafter referred to as accessories, for use when the ambient temperature is normally within the range of -25℃ to +40℃. These accessories are intended to be connected to cables of copper or copper alloy only.
This part applies to accessories with screwless type terminals or insulation piercing terminals, with a rated current up to and including 32 A for series I and 30 A for series II.
The use of these accessories on building sites and for agricultural, commercial and domestic applications is not precluded.
Socket-outlets or appliance inlets incorporated in or fixed to electrical equipment are within the scope of this part. This part also applies to accessories intended to be used in extra-low voltage installations.
This part does not apply to accessories primarily intended for domestic and similar general purposes.
In locations where special conditions prevail, for example on board ship or where explosions are liable to occur, additional requirements may be necessary.
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 3956-2008 Conductors of Insulated Cables (IEC 60228:2004, IDT)
GB/T 4207-2012 Method for the Determination of the Proof and the Comparative Tracking Indices of Solid Insulating Materials (IEC 60112:2009, IDT)
GB 4208-2008 Degrees of Protection Provided by Enclosures (IP code) (IEC 60529:2001, IDT)
GB/T 5023 (all parts) Polyvinyl Chloride Insulated Cables of Rated Voltages Up to and Including 450/750 V [IEC 60227 (all parts)]
GB/T 5169.11-2006 Fire Hazard Testing for Electric and Electronic Products — Part 11: Glowing/Hot-wire Based Test Methods — Glow-wire Flammability Test Method for End-products (IEC 60695-2-11:2000, IDT)
GB/T 5169.21 Fire Hazard Testing for Electric and Electronic Products — Part 21: Abnormal Heat — Ball Pressure Test (GB/T 5169.21-2006, IEC 60695-10-2:2003, IDT)
GB/T 9797 Metallic Coatings — Electrodeposited Coatings of Nickel Plus Chromium and of Copper Plus Nickel Plus Chromium (GB/T 9797-2005, ISO 1456:2003, IDT)
GB/T 9799 Metallic Coatings — Electroplated Coatings of Zinc on Iron or Steel (GB/T 9799-2011, ISO 2081:2008, IDT)
GB/T 11918.4 Plugs, Socket-outlets and Couplers for Industrial Purposes — Part 4: Switched Socket-outlets and Connectors with or without Interlock (GB/T 11918.4-2014, IEC 60309-4:2012, MOD)
GB/T 12599 Electroplated Coatings of Tin — Specification and Test Methods (GB/T 12599-2002, ISO 2093:1986, MOD)
GB 13539.1-2008 Low-voltage Fuses — Part 1: General Requirements (IEC 60269-1:2006, IDT)
GB/T 13539.2-2008 Low-voltage Fuses — Part 2: Supplementary Requirements for Fuses for Use by Authorized Persons (Fuses Mainly for Industrial Application) — Examples of Standardized Systems of Fuses A to I (IEC 60269-2:2006, IDT)
GB/T 16935.1-2008 Insulation Coordination for Equipment Within Low-voltage Systems — Part 1: Principles Requirements and Tests (IEC 60664-1:2007, IDT)
GB 17465 (all parts) Appliance Couplers for Household and Similar General Purposes [IEC 60320 (all parts)]
IEC 60083 Plugs and Socket-outlets for Domestic and Similar General Use Standardized in Member Countries of IEC
IEC 60245-4:2011 Rubber Insulated Cables of Rated Voltages Up to and Including 450/750V — Part 4: Cords and Flexible Cables
3 Terms and Definitions
For the purposes of this document, the following terms and definitions apply.
Note 1: Where the terms voltage and current are used, they imply the d.c. or the a.c. r.m.s. values.
Note 2: The application of accessories is shown in Figure 1.
3.1
Plug and socket-outlet
A means enabling the connection at will of a flexible cable to fixed wiring. It consists of two parts:
3.1.1
Socket-outlet
The part intended to be installed with the fixed wiring or incorporated in equipment.
A socket-outlet may also be incorporated in the output circuit of an isolating transformer.
3.1.2
Plug
The part integral with or intended to be attached directly to one flexible cable connected to the equipment or to a connector.
3.2
Cable coupler
A means enabling the connection at will of two flexible cables. It consists of two parts:
3.2.1
Connector
The part integral with or intended to be attached to one flexible cable connected to the supply.
Note: In general, a connector has the same contact arrangement as a socket-outlet.
3.2.2
Plug
The part integral with or intended to be attached to one flexible cable connected to the equipment or to a connector
Note: The plug of a cable coupler is identical to the plug of a "plug and socket-outlet".
3.3
Appliance coupler
A means enabling the connection at will of a flexible cable to the equipment. It consists of two parts:
3.3.1
Connector
The part integral with, or intended to be attached to, one flexible cable connected to the supply.
Note: In general, the connector of an appliance coupler is identical to the connector of a cable coupler.
3.3.2
Appliance inlet
The part incorporated in, or fixed to, the equipment or intended to be fixed to it.
Note: In general, an appliance inlet has the same contact arrangement as a plug.
3.4
Rewirable plug or connector
An accessory so constructed that the flexible cable can be replaced.
3.5
Non-rewirable plug or connector
An accessory so constructed that the flexible cable cannot be separated from the accessory without making it permanently useless.
3.6
Mechanical switching device
a switching device designed to close and open one or more electric circuits by means of separable contacts.
3.7
Switched socket-outlet
A socket-outlet with an associated switching device to disconnect the supply from the socket-outlet contacts.
3.8
Integral switching device
A mechanical switching device constructed as a part of socket outlet or connector covered by this standard, and the switching device and socket outlet or connector cannot replaced independently.
3.9
Interlock
A device, either electrical or mechanical, which prevents the contacts of a plug from becoming live before it is in proper engagement with a socket-outlet or connector, and which either prevents the plug from being withdrawn while its contacts are live or makes the contacts dead before separation.
3.10
Retaining device
A mechanical arrangement which holds a plug or connector in position when it is in proper engagement, and prevents its unintentional withdrawal.
3.11
Rated current
The current assigned to the accessory by the manufacturer.
3.12
Insulation voltage
The voltage assigned to the accessory by the manufacturer and to which dielectric tests, clearances and creepage distances are referred.
3.13
Rated operating voltage
The nominal voltage of the supply for which the accessory is intended to be used.
3.14
Basic insulation
The insulation necessary for the proper functioning of the accessory and for basic protection against electric shock.
3.15
Supplementary insulation
Protective insulation
An independent insulation provided in addition to the basic insulation, in order to ensure protection against electric shock in the event of a failure of the basic insulation.
3.16
Double insulation
Insulation comprising both basic insulation and supplementary insulation.
3.17
Reinforced insulation
An improved basic insulation with such mechanical and electrical qualities that it provides the same degree of protection against electric shock as double insulation.
3.18
Terminal
A conductive part provided for the connection of a conductor to an accessory.
3.18.1
Pillar terminal
A terminal in which the conductor is inserted into a hole or cavity, where it is clamped under the shank of the screw or screws. The clamping pressure may be applied directly by the shank of the screw or through an intermediate clamping member to which pressure is applied by the shank of the screw [see Figure 14 a)].
3.18.2
Screw terminal
A terminal in which the conductor is clamped under the head of the screw. The clamping pressure may be applied directly by the head of the screw or through an intermediate part, such as a washer, clamping plate or anti-spread device [see Figures 14 b) and 14 c)].
3.18.3
Stud terminal
A terminal in which the conductor is clamped under a nut. The clamping pressure may be applied directly by a suitably shaped nut or through an intermediate part, such as a washer, clamping plate or anti-spread device [see Figure 14 d)].
3.18.4
Saddle terminal
A terminal in which the conductor is clamped under a saddle by means of two or more screws or nuts [see Figure 14 e)]
3.18.5
Lug terminal
A screw terminal or a stud terminal, designed for clamping a cable lug or bar by means of a screw or nut [see Figure 14 f)].
3.18.6
Mantle terminal
A terminal in which the conductor is clamped against the base of a slot in a threaded stud by means of a nut. The conductor is clamped against the base of the slot by a suitably shaped washer under the nut, by a central peg if the nut is a cap nut, or by equally effective means for transmitting the pressure from the nut to the conductor within the slot [see Figure 14 g)].
3.18.7
Screwless type terminal
A terminal for the connection and subsequent disconnection of one or more conductors, the connection being made, directly or indirectly, by other means than screws.
Note: Examples of screwless type terminals are given in Figure 14h.
3.18.8
Insulation piercing terminal; IPT
A terminal for the connection and subsequent disconnection of one or more conductors, the connection being made by piercing, boring through, cutting through, removing, displacing or making ineffective in some other manner the insulation of the conductor(s) without previous stripping.
Note 1: The removal of the sheath of the cable, if necessary, is not considered as a previous stripping.
Note 2: Examples of IPT are given in Figure 14 i).
3.19
Clamping unit
The part of a terminal necessary for the clamping and the electrical connection of the Conductor.
3.20
Conditional short-circuit current
The prospective current that an accessory, protected by a specified short-circuit protective device, can satisfactorily withstand for the total operating time of that device under specified conditions of use and behavior.
Note: This definition differs from IEV 441-17-20 by broadening the concept of current-limiting device into a short-circuit protective device, the function of which is not only to limit the current.
3.21
Cap
A part separated or attached, which may be used to provide the degree of protection of a plug or appliance inlet when it is not engaged with a socket-outlet or connector.
3.22
Lid
A means to ensure the degree of protection on a socket-outlet or a connector.
