Cable plant magna Velikiye Luki: products

VVG cable-ng is a representative of a fairly wide group of conductive products used to provide electricity production shops and offices, for laying in walls, pipes and tunnels, for street lighting. Any electrical work in the construction of private housing or multi-storey buildings requires the use of this particular type of material. The VVG-ng cable is designed for laying in places where it is necessary to avoid fire. It consists of conductive copper filaments enclosed in an insulating sheath and covered with a common film on top. All cable components are designed to continue delivering electricity to its intended destination in the event of a fire.

Types of VVG-ng cable and its marking

Products marked VVG-ng include several types of cable that differ in their characteristics. In order to distinguish each of them, a marking was invented, including information on the composition of the conductive thread and its cross section, on the insulating sheath and its properties, and on the features of the cable.

So, the abbreviation VVG-ng means:

• Thread material - copper (by default). If the thread is aluminum, then the letter A (AVVG) is in front of the designation
• BB - means that PVC compound was used to insulate copper threads and the outer sheath of the cable
• G - means "naked". The cable has no protective coating in the form of a metal plate or other material. Such protection is present in products with a larger cross section.
• ng - means "non-combustible", does not spread combustion when laid alone and in a group. Cable manufacturing technology helps to limit its ignition. Such a cable does not burn in a fire, but melts.

When designating products, other signs can also be used:

• VVG-ng-LS - cable has low smoke emission (LS)
• VVG-ng-NF - cable insulation does not contain halogen materials (NF)
• VVG-ng-P - the cable has a flat shape and can be used for laying under plaster (P), it is fire resistant
• VVG-ng-FRLS - the cable is fire resistant (FRLS) and in the event of a fire will continue to supply electricity for a certain time (usually 60-180 minutes)

As well as letters numbers are used when marking the cable. They reflect the number of copper threads and the cross-sectional area of ​​​​one thread in square millimeters:

• Marking VVG-ng-LS 3 x 50 + 1 x 25 means that the cable has two sheaths made of PVC plastic (copper strands sheath and a common outer sheath - VV), has no protection (G), has low flammability (ng) and low emission smoke (LS). The number of copper threads is 3 with a section of 50 mm (3x50), and one thread has a section of 25 mm (1x25)

The marking also includes the operating voltage of the cable. It is indicated in kilowatts, for example:

• VVG-ng-LS 3 x 50 + 1 x 25 -1 operating voltage of this cable is 1 kV (number 1 in the marking)

The VVG-ng cable is a universal conductive product used in wet conditions and at altitudes up to 4300 meters. Application temperature ranges from +50 to -50°C, maximum allowable humidity - 98% (at +40°C).

Cables of the "NG" version, which are flame retardant when laid in a bundle with a normalized volume of combustible mass of cables in accordance with GOST 12176-89, section 3 (IEC 332-3-96), were developed in 1984-1986. Non-propagation of combustion, depending on the design of the cables, was ensured by using special protective thermal barriers or screens in cable structures, by limiting the volume of combustible materials, using polymer and other materials with low specific heat of combustion and polymer compositions with high oxygen index values. At the same time, cables of the “NG” version during combustion emit a large amount of smoke containing corrosive and toxic products.

In this regard, a set of works was carried out to create polyvinyl chloride compositions with reduced fire risk, on the basis of which it was developed and mastered New episode flame retardant cables with low smoke and gas emission "NG-LS". Index "LS" (low smoke)- compliance with the requirements for smoke generation during combustion of IEC 61034, parts 1 and 2.

Distinctive feature cables of the "NG-LS" version is that their insulation, filling and sheath are made of special polymer compositions of reduced fire hazard created on the basis of polyvinyl chloride. Cables of the "NG-LS" version differ from cables with the "NG" index in that, in addition to flame retardance, they are characterized by a reduced release of hydrogen chloride and low smoke generating capacity during combustion and smoldering. Therefore, the use of cables with the index "NG" in subways Western Europe was banned in the late 1970s.

To solve the problems associated with the release of HCl and smoke, a class of cable materials has been created that do not contain halogens, that is, do not emit corrosive gases and have a significantly lower level of smoke emission - the so-called compositions. Cables using these materials are designated by the index "NG-LS HF". Index "HF" (halogen free) - compliance with the requirements for the corrosiveness of the products of smoke and gas emissions during combustion of GOST R IEC 60754, part 2.

Polymer shell METALANGA corresponds to the index "NG-LS HF" fire safety standards. The combination of a polymer sheath with a metal hose ensures fire safety in the most adverse conditions.

Wire and cable VVGng LS is the top of the family of cable products with the abbreviation VVG, the secret of its privilege is the postscript LS, what it indicates and what it hides, we will analyze in detail in this article.

Indoor smoke is considered the most important factor that increases the risk negative consequences in case of fire. In case of fire at industrial facilities and large public buildings cable routes become one of the main sources of smoke. The sad experience of the Ostankino television tower, the Manege and other disasters of the last decade only confirmed this truth.

Currently, technical regulation documents strictly regulate the types of cable products that can be used for group laying inside public and industrial premises(GOST R 5315-2009). Here, in addition to the condition of non-propagation of combustion (-ng), one of mandatory requirements there was a low smoke and gas emission during combustion or smoldering of the cable.

Designation LS, order of assignment

The decoding of VVGng LS is as follows:

• There is no letter A at the beginning of the marking, which means the cable is copper;
• B - the outer insulating layer consists of PVC insulation;
• B - core insulation consists of PVC insulation;
• ng - does not spread combustion with single and group laying;
• LS- L ow S moke (translated from english easy smoke)

In the marking VVGng (..)-LS, after the category through a hyphen is the designation LS, indicating low smoke and gas emission ( L ow S moke). Of course, such an index can be assigned to a cable only in case of a successful test for such an indicator. The standard procedure for testing for smoke generation during combustion and smoldering, a description of the installation, etc. are given in GOST R IEC 61034 -1 (2) -2005.

The principle of the test is to measure the transparency of the air in the chamber with the cable before and after combustion. The smoke resulting from the combustion of the sample reduces the light transmission of the volume, which is recorded by the instruments. The result of the test will be the ratio of light transmission before and after the experiment, expressed as a percentage. In accordance with GOST R 53769-2010, it is considered that the cable has successfully passed the test if the smoke has reduced transparency by no more than 40%. In this case, the manufacturer has the right to put the LS index in the marking.

Cable insulation with low smoke emission

For the production of VVGng LS cable, PVC compounds of reduced fire hazard are required, and, in contact with fire, they should not give a large number smoke. In addition, it is required that the smoke be minimally toxic (the toxicity index is not more than 40 mg / m 3 according to GOST R 53769-2010).

The task is difficult, but it was successfully solved by selecting special additives - antipyrines and additives. Today, such plastic compounds are produced both in Russia and abroad. Domestic manufacturers have registered several TUs, for example TU 2246-001-25795756-2009, and produce plastic compounds for them, specialized for core insulation, internal filling and outer sheath (grades PPI 30-30, PPV-28, PPO30-35, respectively).

Cable structure VVGng LS

The composition and arrangement of the elements of the VVGng (..) -LS cable is no different from its counterparts - cables with copper conductors, with PVC insulation and sheath according to GOST 53769-2010. External similarity is clearly visible in the image shown in this section.

Cable VVGng(..)-LS can be round and flat, maximum amount lived five. The cores themselves can be single-wire or multi-wire, round or sector. The nominal values ​​​​of the cross-sectional areas are selected from a single standard series for all.

VVGng LS cable specifications

Since the characteristics of the entire family of cables with PVC core insulation and sheath are standardized by one standard GOSTR 53769-2010, they vary only within small limits for different manufacturers. The standard does not introduce separate indicators for the cross-sections and shape of the cores, the thickness of the insulation of conductors and sheaths, electrical resistance, etc. for cables with insulation made of plastic compounds with reduced smoke generation. They go along with the whole family of PVC compounds. Separate values ​​are given for XLPE insulation, etc.

GOSTR 53769-2010 provides for -LS products some difference in minimum tensile strength, it may be less than that of VVG, but does not differ from VVGng. Therefore, the section "VVGng LS cable specifications"in terms of general characteristics, it practically does not differ from the section of the same name in the article, the cable of the VVG brand. Familiarize yourself with general characteristics VVGng(..)-LS is possible.

Application of cable VVGng(..)-LS

Cables VVGng - LS related to fire hazard classes P1.8.2.1.2 and

P1.8.2.2.2 can be used for group laying in residential and public buildings, internal and external cable structures on industrial enterprises. It is allowed to use the cable at nuclear facilities.

Other cable options

• - round copper wire with PVC insulation of the outer and inner layers, has low gas and smoke emission during combustion with single and group laying;
• VVG-P - the same as VVG, but flat design;
• - round copper wire with PVC insulation of the outer and inner layers, has low gas and smoke emission during combustion with a single laying;
• VVGng-P - the same as VVGng, but flat design;
• VVGng-ls - round copper wire with PVC insulation of the outer and inner layers, has low gas and smoke emission during combustion in single and group laying;
• VVGng-Pls - the same as VVG-ls, but flat design;
• VVGng-frls - round copper wire with fire-resistant PVC insulation of the outer and inner layers, has low gas and smoke emission during combustion in single and group laying;
• VVGng-Pfrls - the same as VVGng-frls, but flat design.

Each strategically important facility is unlikely to be able to do without the use of fire-resistant cable. It is used as a high-tech tool for the transmission and distribution of electricity and signals. Fire-resistant, non-combustible cable is an indispensable component of fire protection systems, smoke protection and warning and evacuation systems.

Application area

Fire-resistant cable products with low smoke emission KSRV ng(A)-FRLS and KSREV ng(A)-FRLS (similar to KPSEng (A)-FRLS, KPSng (A)-FRLS) are intended for group and single laying in various systems fire safety: management of evacuation in case of fire, fire alarm, emergency alert, fire detection, ventilation systems and means of automatic fire extinguishing. This cable product remains operational for three hours in a fire. Very successfully used to maintain the level of fire safety in industrial enterprises, shopping malls, medical and educational institutions, multi-storey buildings and office premises.

In rooms, the cable can be laid in special channels, along blocks, walls, ceilings, on supporting structures, in hidden or open ways.

Description of cable products

KSRVng(A)-FRLS cable is a cable of pair twisting, with single-wire copper conductors (diameter - 0.5, 0.80, 0.97, 1.13, 1.38 mm). Covered with insulating, ceramized silicone rubber, sheathed with PVC-compound with fire hazard reduction properties and minimal combustion toxicity.

Cable KSREV (A)-FRLS has all of the above characteristics, but in addition this species The cable is provided with a screen made of aluminum polymer tape, which performs the function of protection against electromagnetic interference.

Regulatory Compliance

The fire-resistant cable fully complies with the requirements of all regulatory documents, including the “Technical Regulations on Fire Safety” GOST R 53315. The products are certified according to the class P1 b fire safety system. 2.2.2. the GOST standard mentioned above.

Cable Specifications

• Fire resistance of the cable in case of fire - 180 minutes;
• Operating temperature range from -40 to +70 °C;
• Operation of cables at alternating voltage - 250V;
• Work of cables in conditions direct current- 300V;
• The maximum service life is 20 years;
• Manufacturer's warranty - 12 months.

Advantages of fire resistant cable products

The advantages of fire-resistant cables KSRV ng(A)-FRLS and KSREV ng(A)-FRLS are obvious. They do not propagate the combustion process both singly and in a beam. Able to perform their functions in case of fire for a long time. Also an important advantage is that the cable does not emit hazardous to human health during combustion. chemical substances: fluorine, bromine, chlorine and other corrosive gases.

New regulatory requirements developed in accordance with Federal Law No. 123 "Technical

Regulation on fire safety requirements", regulate the need

Use in the installation of communication lines fire-resistant cable to ensure the required

System uptime in case of fire.

According to clause 4.1 of the set of rules SP 6.13130.2009 "Fire protection systems.

Electrical equipment. Fire safety requirements": " cable lines systems

fire protection must be carried out with fire-resistant cables with copper conductors, not

Flame-propagating for group laying according to category A according to GOST R IEC 60332-3-22

Low fume and gas emission (ng-LSFR) or halogen-free (ng-HFFR)."

Preferred areas of application of cable products, taking into account their type of execution

Defined in GOST R 53315-2009 and GOST R 53769-2010.

Primary scope of fire-resistant cable

When designing security systems, a cable is often included in the project with the ending

In the marking ng -FRLS (for example, the cable KPSeng FRLS 1x2x0.5), although it is more logical to use

Cable ng-FRHF (KPSEng FRHF 1x2x0.5).

The LS index, which is an abbreviation for Low Smoke, literally means "low

Smoke emission" seems to be more understandable compared to the HF - Halogen Free index, which

Means "halogen-free". Perhaps this is the reason why more

Applied ngFRLS cable than flame retardant cable with ngFRHF index. Obviously the role is the same

The fact that the price is always a little lower for the KPSeng FRLS cable plays.

According to GOST R 53315--2009 with amendment No. 1 "Cable products. Fire safety requirements

Safety "ngFRLS cable is used" for laying, subject to the amount of combustible load

Cables, in internal electrical installations, as well as in buildings, structures and closed cable

Structures", while the fire-resistant cable ng FRHF - "for laying, taking into account the volume of combustible

Cable loads, in internal electrical installations, as well as in buildings and structures with mass

The stay of people, including in multifunctional high-rise buildings and buildings -

Complexes".

Cable fire hazard class

According to GOST R 53315--2009 in the designation of the fire hazard class:

• the first indicator is the flame propagation limit (O1 or O2 for a cable, tested singly, or P1 - P4 for a cable product tested during group laying)
• the second is the fire resistance limit;
• the third is an indicator of corrosion activity;
• the fourth is an indicator of toxicity;
• the fifth is the indicator of smoke formation.

So a cable with a declared fire resistance of at least 180 minutes of the ng (A) -FRLS type (for example, KPSEng

FRLS 1x2x1) has a fire hazard class P1b.1.2.2.2

Cable type ng(A)-FRHF (for example cable KPSeng FRHF 1x2x1) - has a fire hazard class

P1b.1.1.2.1. Accordingly, the use of the ng(A)-FRHF cable provides not only the minimum

Emission of corrosive gases, but also significantly less smoke emission compared to

Cable ng(A)-FRLS. Therefore, for complete clarity, the cable ng (A) - FRHF is correctly called

Flame retardant, halogen-free and smokeless, flame retardant in group

Gasket.

Halogens, Corrosivity and Toxicity

ngFRLS cable (for example, KPSEng FRLS 2x2x1 cable) when exposed to high temperatures and

The flame releases halogens. The most famous of them are chlorine and fluorine. They are poisonous and

Vigorous oxidizing agents that cause corrosion, which seriously limits the possibilities of application

Such a cable. In case of fire, highly toxic chloride gas

Hydrogen, escaping from the cable insulation that collapses under the influence of temperature,

It spreads over the object and, connecting with water vapor, condenses in the form

concentrated hydrochloric acid.

Permissible according to GOST R 53769-2010 values ​​of indicators of corrosive activity of products

Smoke and gas emissions during combustion and smoldering of insulation materials, shells and protective

Cable hoses with index LS and index HF differ by 28 times!

Smoke emission

The ngFRLS cable (for example, the KPSEng FRLS 1x2x0.75 cable) is quite smoky - when it

Destruction in a flame according to GOST R 53315-2009, a decrease in light transmission up to 50% is permissible,