Basic Knowledge of Electric Wire and Cable

(I) The concept of wires and cables and the distinction between wires and cables: wires and cables are materials used for power, communication and related transmission purposes. "Wire" and "cable" do not have a strict boundary. Products that usually have small core numbers, small product diameters, and simple structures are called wires, naked wires without insulation, and others are called cables; The larger conductor cross-sectional area(greater than 6 square millimeters) is called a large wire, the smaller(less than or equal to 6 square millimeters) is called a small wire, and the insulated wire is also called a cloth wire. Wire and cable mainly include naked wire, electromagnetic wire and electrical electrical insulation wire, power cable, communication cable and cable.

Wire and cable naming: The complete naming of wire and cable is usually more complex, so people sometimes use a simple name(usually the name of a category) in combination with the model specification instead of the complete name. Such as "low voltage cable" represents 0.6 / 1 kV class of all plastic insulated power cables. The profile of the wire and cable is relatively complete. It can be said that as long as the standard model specifications of the wire and cable are written, the specific product can be clearly defined, but what is its complete name?

The naming of wire and cable products has the following principles:

1, the content included in the product name(1) product application or size class name(2) product structure material or type; (3) The important features or additional features of the product are basically named in the above order, and sometimes in order to emphasize important or additional features, the features are written before or before the corresponding structure description.

The order of structure description The product structure description is based on the principle of inward and outward: conductor -- --; Insulation -- & GT; Inner guard layer-& GT; Protection layer-& GT; Armor type.

3, simplify without causing confusion, some structural descriptions save or shorthand, such as car lines, soft lines are not allowed to use aluminum conductors, so do not describe conductor materials. Example: rated voltage 8.7 / 15kV flame-retardant copper core cross-linked polyethylene insulated steel belt gauntlet PVC sheath power cable "rated voltage 8.7 / 15kV"-use/voltage grade "flame-retardant"-emphasized feature "copper core"-conductor material "cross-link Polyethylene insulation "-insulating material" steel belt armor "-armored layer material and type(double steel gap wrap)" PVC sheath "-internal and external sheath material(both internal and external sheath materials are the same, Save the cover material) "power cable"-the category name of the product and the corresponding model are written as ZR-YJV22-8 .7 / 15. The wording of the model is described below.

Model: The model composition and order of wire and cable are as follows:[ 1: Category, purpose] [ 2: Conductor] [ 3: Insulation] [ 4: Inner Guard] [ 5: Structural characteristics] [ 6: Outer layer or derivative] -[Sighs] 7: Use features] Items 1-5 and 7 are represented by Pinyin letters, and polymer materials are represented by the first letter of the English name, each of which can be 1-2 letters; Item 6 is 1-3 numbers.

The principle of omission in the model: Copper is the main conductor material used in wire and cable products, so the copper core code T province is written, except for naked wires and bare conductor products. Naked wires and bare conductor products, power cables, and electromagnetic wire products do not indicate the main type of code, and electrical equipment wires and cables and communication cables are not listed, but small or series codes are listed. Item 7 is a mark for various special uses or additional special use requirements. It is marked with Pinyin letters after "-''. Sometimes in order to highlight the item, write the item first. Such as ZR-(flame retardant), NH-(fire resistant), WDZ-(low smoke without halogen, enterprise standard),-TH(wet hot area), FY-(anti-termite, enterprise standard) and so on. Digital Mark coat outer coat or outer sheath 0 No-1 interlocking armor fiber outer 2 double steel with PVC coat 3 thin wire polyethylene coat 4 thick round steel coat 5 wrinkles(rolling) steel belt 6 double aluminum(or aluminum alloy) with 8 Copper wire braiding 9 wire braiding