1. Standard test method for single cable non-burning
A test cable is suspended in a dedicated burner, the flame temperature at the cable reaches a certain value (exceeding the ignition temperature), a few minutes later, the ignition source is removed, and then the test cable is put out.

2. Material Oxygen Index method
will be a certain number of size test samples into a special container, filled with nitrogen, gradually filled with oxygen, in different oxygen content, in the prescribed way to ignition, so that the test material in the container in a stable combustion oxygen content is called the Oxygen Index.

3. Standard test method for flame-retardant examination of cables through holes
The United States, Sue, Japan, countries on the cable through the hole to make use of blocking material flame-retardant, have developed a standard test method, in a special furnace, according to the standard temperature curve gauge? "Time-temperature" change speed heating effect on the test wire and cable one end of the furnace wall through the cable sealing treatment mode, after 1-3h heating, observation of the outside of the Furnace cable section master does not burn or intact, to determine the sealing material flame resistance characteristics.

4. Standard test method for flame resistance of bunched cables
The basic principle of the standard test method is the same as that of single cable. Domestic wire and cable manufacturers have been modeled after the iec382-2 new Standard and IEEC-383, ICS-366 standard set of testing equipment. The experiment of simulating cable tunnel, cable shaft and cable interlayer is also organized, and reliable test data are obtained.

Flame-Retardant cable means: under the prescribed test conditions, the specimen is burned, after the removal of the fire source, the flame spread only within the limited range, residual flame or residual burning in the limited time to extinguish the cable itself. Its basic characteristics are: In the case of fire may be burned to run, but can prevent the spread of the fire. Generally speaking, the cable in case of fire, can limit the combustion in the local scope, do not produce the spread of other equipment, to avoid causing greater loss.

The structure of the flame-retardant cable is basically the same as that of the ordinary cable, except that its insulating layer, sheath, outer layer and auxiliary material (packing and filling) are all or part of the flame retardant material.

Fire-resistant cable means: under the prescribed test conditions, the specimen is burned in the flame and can maintain its normal operating performance for a certain period of time. Its fundamental characteristic is that the cable can maintain the normal operation of the line for a period of time under burning condition. Popularly speaking is, in case of fire, the cable will not burn, the circuit is relatively safe.

The structure of the fire-resistant cable is basically the same as that of the ordinary cable, except that the conductor of the fire-resistant cable adopts a copper conductor with good fire resistance (the melting point of the copper is 1 083 ℃), and a refractory layer is added between the conductor and the insulating layer. The refractory layer is formed by the multiple cloud mother belt wrapping. Because the different mica belt's allowable working temperature difference is big, therefore the cable fire resistance performance key is the Mica belt.

Therefore, the main difference between fire-resistant cable and flame-retardant cable is that the fire-resistant cable can maintain a normal power supply for a period of time while the fire-retardant cable does not have this characteristic. This feature determines that fire-resistant cables play an important role in modern urban and industrial buildings.
Because once the fire occurred, control, surveillance, guidance and alarm system power supply circuit must maintain normal operation. Therefore, the cable is mainly used in emergency power supply to the user fire equipment, fire alarm equipment, ventilation exhaust equipment, guide lights, emergency power sockets, emergency elevators and other power supply circuit.

One: View the section cable the most inner part is to the electric core
Once outward is the insulating layer of the half conductive layer, shielding layer and filling layer. Now the market has a lot of businesses will use low-quality goods to impersonate, if the use of some unqualified products for the cable filling, some future more benefits, but a part to test the market, in order to later can very good speculation, increase the interests of businessmen, expand the source of profit circle.

Second: Check the thickness of insulating layer
General Low-voltage Cable insulation layer thickness is very thin, low pressure is about 1-3 high pressure is probably lower than the thickness of the low, his pressure is higher, that is, his resistance is less than the low-voltage cable, low voltage cable is not easy to heat, so it is not prone to fire phenomenon, for high-voltage cable, this is a big drawback, low-voltage cable is only one layer of protective sleeve.

III: How to distinguish between High-voltage and low-voltage power cable
The High-voltage cable has an insulating layer after removing the outer skin. is wrapped in the cable core outside, white like the main insulating layer of plastic, low-voltage cable is not this an important insulating protective layer, his resistance is very poor, white like the main insulating layer of plastic, low-voltage cable is mainly not this main insulating layer.

Power cables are cables used to transmit and distribute electricity, the power cable is used in the underground power grid of the city, the power supply of the industrial and mining enterprise and the transmission line of the water over the river, the proportion of the electric cable is increasing, the power cable is the cable product of the power system used for transmission and distribution in the main trunk line.

High-voltage cable in the installation of the same need to ground, the purpose is to facilitate the detection of the cable lining of the good or bad, in the detection of cable protection, steel armored and copper shielded cable, if the voltage can withstand is to prove that the inner layer is intact.
His grounding method is the sheath one end of the direct grounding, the other end is protected through the protective layer grounding, the two ends of the sheath grounding this method is less used, just suitable for use in the short and small load of the cable line.

Introduction to production process of wire and cable

Single-Core installation line
1, conductor → insulation injection → withstand pressure test → Test qualified → roll packing → factory
2, conductor → conductor stranded wire or bundle wire → insulation injection → withstand pressure test → Test qualified → packing → factory

Sheath Mounting Line
1, conductor → insulation injection → pressure test → combined sheath injection → inspection qualified → packing → factory
2, conductor → conductor stranded wire or bundle of wire → insulated injection molding → withstand pressure test → combined sheath injection → test qualified → packing → factory

Special single-Core installation line
1, conductor → high temperature F46 injection or silicone rubber insulation → withstand pressure test → Test qualified → to roll packing → factory
2, conductor → conductor stranded wire or bundle wire → high temperature F46 injection or silicone rubber insulation → withstand pressure test → Test qualified → roll packing → factory

Special Sheath Installation Line
1, conductor → high temperature F46 injection or silicone rubber insulation → pressure test → combination sheath high-temperature F46 injection or silicone rubber → inspection qualified → packing → factory
2, conductor → conductor stranded wire or bundle wire → high temperature F46 injection or silicone rubber insulation → withstand pressure test → combine sheath high-temperature F46 injection or silicone rubber → test qualified → roll packing → factory

Compensating wire or compensating cable
1, conductor → insulation injection → pressure test → combined sheath injection → inspection qualified → packing → factory
2, conductor → insulation injection → withstand pressure test → merge shield weaving → sheath injection → inspection qualified → packing → factory
3, conductor → High temperature F46 injection molding or silicone rubber insulation → pressure test → combination shielding weaving → sheathed high-temperature F46 injection or silicone rubber → inspection qualified → packaging → factory

Power cable
1, conductor → insulation injection → pressure test → into a cable or Gagang → sheath injection → test qualified → packing → factory
2, conductor → conductor strand → insulation injection molding → pressure test → into a cable or Gagang → sheath injection → inspection qualified → into the plate packing → factory

Special Power cable
1, conductor → high-temperature F46 injection or silicone rubber insulation → pressure test → into a cable or Gagang → sheath high-temperature F46 injection or silicone rubber → Test qualified → into the plate packing → factory
2, conductor → high-temperature F46 injection or silicone rubber insulation → pressure test → into a cable or Gagang → sheath high-temperature F46 injection or silicone rubber → Test qualified → into the plate packing → factory

I. Ecological and environmental protection
Environmental protection products will be the trend of the future. With the EU issued RoHS Directive, eco-friendly wire and cable research and development and large-scale adoption has become an international trend. At present, the application of fire-retardant and fireproof cable has been extended to many fields, such as mine, general rubber sheath cable, elevator cable, and household appliance cables have different degrees of flame-retardant requirements.
The use of halogen-free low smoke crosslinked polyolefin insulated wire and cable has become a local regulation in these areas. With the increase of people's awareness of environmental protection and safety, eco-friendly cable will be the product direction of future industry development.

II. Special
Domestic cable industry shouting to "Occupy high-end market", occupy high-end market basically can be said to occupy the special cable market. Because of the current high threshold of special cable, high profit margins, competition is more moderate, so the high-end market is undoubtedly the domestic cable industry in front of a visible "big fat." As special cable can meet the special circumstances and special occasions need, coupled with the ability to produce special cables need a strong own equipment, the threshold is relatively high, so special cable will become the future market "darling", the ability of the cable enterprises will rise "Zhengchong".

III. High pressure and ultrahigh pressure
Ultra-high voltage cable as a special type of cable, the reason for the introduction of a separate, is because UHV cable in the future market demand, is "a solo show", UHV construction will rise to the height of the national strategy, thus to the cable production industry has brought huge waves, UHV cable will demand exuberant.

IV. Refinement
The so-called product refinement, its raw materials used more refined, using less raw materials can have more powerful performance. such as fiber optic cable with skeleton, it can be laid through pipes, overhead and so on, with small cable diameter, light weight and good resistance to side pressure; The halfway can be at any time under the fiber, construction and installation convenient;

HDMI Forum Inc. announced that the HDMI 2.0 standard specification has been finalized and released, greatly enhancing the support for 4K ultra-high-definition transmissions, and improving on multiple video and audio technologies. HDMI 1.4 already can support 4K, why should launch HDMI 2.0 yet, what difference do they have, PCER electronic will tell the detailed analysis.

First, hdmi 2.0 does not define new data lines and connectors and interfaces, so it can maintain perfect backward compatibility with hdmi 1.x. The existing two types of data lines can be used directly.

Second, hdmi 2.0 version of the standard specification has been formulated and released, greatly enhancing the support for 4K ultra-high-definition transmission, and in a number of video and audio technology has been improved.

Third, hdmi 1.4 can already support 4K, but subject to bandwidth, the highest can only reach 3840 × 2160 resolution and 30FPS frame rate, hdmi 2.0 will expand the bandwidth to 18Gbps, can support 3840 × 2160 resolution and 50FPS, 60FPS frame rate. At the same time support up to 32 channels in audio, and the highest sampling rate of 1536kHz.

Other major improvements:

- Simultaneous transmission of dual video streams to multiple users on the same screen

- Simultaneous transmission of multiple audio streams to up to four users

- Supports 21:9 widescreen display

- Dynamic synchronization of video and audio streams

- The cec extension gives better control over consumer electronics devices through a single point of control

All in all, HDMI 2.0 does not define new data lines and connectors and interfaces, so it can maintain perfect backward compatibility with HDMI 1.x. Existing Type 2 data lines can be used directly.

HDMI 2.0 will not replace HDMI 1.x, but based on the latter's enhancements, any device that wants to support HDMI 2.0 must first ensure basic support for HDMI 1.x.

Wire and cable through a certain load current, will be hot, as the load current increases, the wire surface temperature higher, if not timely treatment, the consequences can be imagined. such as: PVC (PVC) wire, is the core temperature of 70 degrees for the upper limit, surface temperature will be low 5~10℃. So the wire surface temperature below 60 degrees is basically safe, from the power maintenance considerations, of course, the lower the temperature the better.

Power lines are running in the following reasons:
1, the wire conductor resistance does not meet the requirements, resulting in the operation of the wire in the heat phenomenon.
2, the improper selection of wire, resulting in the use of the conductor cross-section of the wire too small, the operation of the phenomenon of overload, the long time after use, the heat and heat of the wires caused by uneven heating phenomenon.
3, wiring installation is too dense, ventilation cooling effect is not good, or wire near other heat sources too close, affecting the normal heat of the wire, but also may cause the wire in the operation of the phenomenon of fever.
4, the joint manufacturing technology is not good, the pressure is not close, resulting in contact resistance is too large, will also cause heating wires.
5, wire insulation performance is not good, resulting in small insulation resistance, the operation will also produce heating phenomenon.
6, armored wire local sheath breakage, after the water to the insulation performance caused by slow damage, resulting in insulation resistance gradually reduced, will also lead to the operation of wire heating phenomenon.
Power lines after heating phenomenon, such as not to find the cause of timely troubleshooting, the wires continue to run continuously after electricity will produce insulation thermal breakdown phenomenon. Causes the electric wire to occur the short circuit tripping phenomenon, serious may cause the fire.

Wire and cable industry is "material heavy industry light" industries, material costs about the cost of products 65%~85%. Therefore, it is one of the important ways to reduce the product cost and improve the competitiveness of the enterprises by selecting the material with the performance-price ratio and ensuring the quality of the materials.

Common material quality issues are as follows:
1, copper rod: With recycled copper manufacturing, surface oxidation discoloration, insufficient rally, such as roundness.
2, PVC plastic: impurities, heat weight loss unqualified, extruded layer of gas hole, hard to plasticizing, color is not.
3, Xlpe insulation material: short time to Scorch, easy to early crosslinking and so on.
4, silane crosslinking material: Poor extrusion temperature control, thermal extension difference, surface roughness and so on.
5, Copper Belt: uneven thickness, oxidation discoloration, insufficient tensile strength, lotus leaf edge, softening insufficient, hard, short head more, consecutive bad, paint film or zinc layer fall off, etc.
6, steel wire: Outside diameter is large, zinc layer falls off, galvanization is insufficient, short head is more, pull not enough wait.
7, PE filling bar: Hard, easy to break, Radian is wrong.
8, Non-woven Fabric: The actual thickness of the goods do not version, the tension is not enough, when the width is uneven.
9, PVC tape: Partial thickness, pull not enough, short head, uneven thickness.
10, Refractory mica tape: Layering, insufficient tensile strength, sticky, with a plate wrinkle and so on.
11, no alkali rock cotton rope: uneven thickness, insufficient rally, joint, easy falling powder and so on.
12, glass Ribbon: Partial thickness, ladder, the preparation of small density, mixed organic fiber, easy to tear and so on.
13, halogen-free coating of flame-retardant belt: Easy to break, with a plate wrinkle, ladder, flame-retardant poor, smoke and so on.
14, heat shrink cap: The size of the specification is not allowed, the material memory is poor, the long burn shrinkage, the intensity is inferior.

Some materials manufacturers one-sided pursuit of reducing costs, or blindly cater to the user's low price requirements, and shoddy, jerry-building, resulting in the material quality of the use of the requirements, wire and cable manufacturers to cause direct economic losses, so the return, wrangling, refused to pay the things often occur, so that both sides are The correct attitude should be, both sides of the supply and demand consensus, to discuss both reducing material costs and not affect product quality, mutual benefit and common development.