In our life, people's understanding of wires and cables may be limited to household wires and external general cables, but in practical use, wires and cables involve more fields. Today, let's introduce the basic concepts and knowledge of wires and cables

Wire and cable are wire products used to transmit electromagnetic energy, information and realize electromagnetic energy conversion. Wires and cables in the broad sense are also referred to as cables, and cables in the narrow sense refer to insulated cables, which can be defined as: an aggregate composed of the following parts; One or more insulated cores, as well as their possible cladding, total protective layer and outer protective layer. The cable can also have additional uninsulated conductors.

Main classification

Bare wire body products

The main features of this kind of products are: pure conductor metal, without insulation and sheath layer, such as steel cored aluminum strand, copper aluminum busbar, electric locomotive line, etc; The processing technology is mainly pressure processing, such as melting, calendering, drawing, stranding / compression stranding, etc; The products are mainly used in suburban, rural, user main line, switch cabinet, etc.

power cable

The main features of this kind of products are: extruding (winding) the insulation layer outside the conductor, such as overhead insulated cable, or several cores stranded (corresponding to the phase line, zero line and ground wire of power system), such as overhead insulated cable with more than two cores, or adding sheath layer, such as plastic / rubber sheathed wire and cable. The main process technologies include drawing, stranding, insulation extrusion (wrapping), cable forming, armor and protective layer extrusion. The different process combinations of various products are different.

The products are mainly used for strong electric energy transmission in power generation, distribution, transmission, transformation and power supply lines, with large current (tens of amps to thousands of AMPS) and high voltage (220V to 35kV and above).

Wires and cables for electrical equipment

The main features of these products are: a wide range of varieties and specifications, a wide range of applications, and more use voltages of 1kV and below. In the face of special occasions, new products are constantly derived, such as fire-resistant cables, flame-retardant cables, low smoke halogen-free / low smoke low halogen cables, anti termite, anti mouse cables, oil / cold / temperature / wear-resistant cables, medical / agricultural / mining cables, thin-walled wires, etc.

Model naming

Basic concepts

The complete naming of wires and cables is usually complex, so people sometimes use a simple name (usually the name of a category) combined with model specifications to replace the complete name. For example, "low voltage cable" represents all plastic insulated power cables of 0.6/1kv grade. The type spectrum of wires and cables is relatively perfect. It can be said that as long as the standard models and specifications of wires and cables are written, the specific products can be defined, but what is its complete naming?

The naming principles of wire and cable products are as follows:

1. Content included in product name

(1) name of product application occasion or size category

(2) product structure, material or type;

(3) important features or additional features of the product

It is basically named in the above order. Sometimes, in order to emphasize important or additional features, the features are written in front of or in front of the corresponding structural description.

2. Order of structure description

The product structure description is based on the principle from inside to outside: conductor -- > insulation -- > inner sheath -- > outer sheath -- > armor type.

3. Simplify

Without causing confusion, some structure descriptions are omitted or abbreviated. For example, aluminum conductors are not allowed in automobile wires and flexible wires, so conductor materials are not described.

Case:

Rated voltage 8.7/15kv flame retardant copper core XLPE insulated steel tape armored PVC sheathed power cable

"Rated voltage 8.7/15kv" - application occasion / voltage level

"Flame retardant" - emphasized features

"Copper core" - conductor material

"XLPE insulation" - insulating material

"Steel strip armor" - material and type of armor layer (double steel strip gap wrapping)

"PVC sheath" - inner and outer sheath materials (the inner and outer sheath materials are the same, and the inner sheath materials are omitted)

"Power cable" -- name of product category

The corresponding model is zr-yjv22-8.7/15. See the description below for the writing method of the model.

4. Use the capital of the first letter of Chinese pinyin to indicate the insulation type, conductor material, inner sheath material and structural characteristics. If Z represents paper; L stands for aluminum; Q stands for lead; F stands for split phase; Zr stands for flame retardant; NH stands for fire resistance.

5. The composition of the outer sheath is represented by numbers, with two digits. No number means no armor layer and no outer coating. The armored steel wire is represented by the first digit and the armored steel wire is represented by the second digit.

⒍ according to the arrangement of cable structure, the general order of cable models is: insulating materials; Conductor material; Inner sheath; Outer sheath.

⒎ cable products are indicated by model, rated voltage and specification. The method is to add the rated voltage, number of cores and nominal cross-sectional area after the model.

list

RV，RVV，RVVP，RVVY，RVVYP，KVVRP，（N）2YSLC，ZR-RE，ZR-REE，ZR-REEP，PUR，LIYY，LIYCY，LIYY(TP），LIYCY(TP) ，LI2YCY，PIMF，LIHH，LIHCH。

characteristic

CEF - ethylene propylene rubber insulation, neoprene sheath, marine flame retardant power cable.

CVV - PVC insulated, PVC sheathed marine flame retardant power cable.

BV, BX, RV and RVV series wires are often used for oxygen cabin wires, including:

Bv - copper core PVC insulated wire, with long-term allowable temperature of 65 ℃, minimum temperature of - 15 ℃, working voltage of AC 500V and DC 1000V, which can be fixed indoors and outdoors, and can be laid in open or concealed.

BX - copper core rubber insulated wire, the maximum service temperature is 65 ℃, which is applied indoors.

RV - PVC insulated single core flexible wire, the maximum service temperature is 65 ℃, the minimum service temperature is - 15 ℃, and the working voltage is AC 250V and DC 500V. It is used as the internal wiring of instruments and equipment.

RVV - copper core PVC insulated and sheathed flexible wire. The allowable long-term working temperature is 105 ℃, and the working voltage is 500V AC and 1000V DC. It is used in wet, high mechanical protection requirements, frequent movement and bending.

Common models

VV: PVC insulation (first V), PVC sheath (second V)

Yjv22 means: cross linked polyethylene insulation (YJ), PVC sheath (V), steel tape armor (22)

The model with "Zr" or "fr" is flame retardant cable (wire). Add "L" for aluminum wire

The model of wire is simple:

BVV -- PVC insulated and sheathed copper core wire,

Bv -- PVC insulated copper core wire,

BVR -- PVC insulated copper core flexible wire,

BX -- rubber insulated copper core wire,

RHF -- neoprene rubber sheathed copper core cord.

Scope of application

Power system 

The wire and cable products used in the power system mainly include overhead bare wires, bus bars (buses), power cables (plastic cables, oil paper power cables (basically replaced by plastic power cables), rubber sheathed cables, overhead insulated cables), branch cables (replacing some buses), electromagnetic wires and electrical equipment wires and cables for power equipment, etc.

Information transmission system

The wires and cables used for information transmission system mainly include local telephone cable, TV cable, electronic cable, RF cable, optical fiber cable, data cable, electromagnetic cable, power communication or other composite cables.

Mechanical instrument system 

This part is applied to almost all products except overhead bare wires, but mainly power cables, electromagnetic wires, data cables, instrument cables, etc

This article explains some basic knowledge of wires and cables to you. I believe you have a certain understanding of this. I hope you can have a certain reference value for readers through the above introduction. If you want to know more or have any needs, you can log in to renhotec platform and contact us at any time.