KGTP or PVS: which flexible wire should I choose?

Introduction: Two Flexible Copper Conductors

KGTP and PVS are two copper conductors that are often confused because of their external similarity and flexibility. Both are multi-strand, both are used for connecting electrical equipment, but they are created for different conditions. KGTP is a flexible power cable with rubber insulation, designed for heavy operating conditions. PVS is a connecting wire with polyvinyl chloride insulation, familiar in household extension cords and electrical appliances.

The difference in insulation material determines the main thing: KGTP remains elastic in frost down to –40 °C, withstands impacts, oils and ultraviolet; PVS stiffens already at –25 °C and is not intended for outdoor use. At the same time, PVS is cheaper, lighter and easier to strip. The choice between them is a choice between a professional tool and a household solution. More about the characteristics of PVS is given in the review about PVS wire, and about KGTP — in the material kgtp cable.

Comparative Table of KGTP and PVS

Design, Insulation and Frost Resistance

KGTP stands for flexible cable, with rubber insulation and sheath, increased frost resistance, tropical version. The letter “T” indicates the tropical version, “P” — a rubber sheath of increased strength. Ethylene propylene rubber insulation retains elasticity in severe frosts, and the black rubber sheath resists abrasion and petroleum products. Such a cable calmly lies on frozen ground, cars drive over it, it does not break at –40 °C.

PVS is a wire with vinyl insulation and a vinyl sheath, connecting. PVC compound is cheap and technological, but at –10 °C it already hardens, and at –25 °C it becomes brittle. Any attempt to bend such a wire in the frost leads to cracks. Therefore, PVS is categorically unsuitable for outdoor winter work. Its element is warm rooms, where the temperature is stable and mechanical loads are minimal. The difference between PVS and VVG, with which it is also often confused, is analyzed in the article PVS or VVG.

Electrical Parameters, Load and Power

Both conductors are manufactured with stranded copper conductors. The permissible continuous current depends on the cross-section. For PVS 3×2.5 mm² it is about 25 A, which at a single-phase 220 V network corresponds to a power of 5.5 kW. For KGTP 3×2.5 the current is similar, but thanks to the more heat-resistant insulation, the cable tolerates short-term overloads better. The rated voltage of KGTP is 660/1000 V, PVS — 450/750 V, that is, for a three-phase 380 V network PVS is suitable with a margin, but in industrial circuits with possible surges up to 660 V KGTP is preferable.

The 3×2.5 cross-section is the most popular for portable tools and extension cords. For welding machines, KGTP 3×4 or 3×6 is used, since currents can reach 40–60 A. PVS of such cross-sections is also produced, but its sheath will not withstand contact with hot metal and sparks. The weight per metre of KGTP is higher than that of PVS of the same cross-section due to the denser rubber sheath, but this difference is compensated by strength.

Application: Home, Construction Site, Outdoor

PVS is a wire for the home. It is used to equip washing machines, refrigerators, electric kettles; extension cords, splitters, and portable leads are made from it. It is light, flexible, pleasant to the touch, and easy to strip. For connecting lamps, computer equipment, and small tools indoors, there is no better solution for its price. Its insulation is not afraid of moisture, but only within the apartment.

KGTP is a cable for professionals. Construction sites, quarries, factories, ships, agriculture — everywhere where the wire is dragged on the ground, thrown under rain and snow, where a guarantee is needed that the insulation will not crack or wear through. The oil- and petrol-resistant sheath allows laying it next to operating machine tools without fear that the emulsion will corrode the plastic. Outdoors, KGTP serves for years without additional protection, which cannot be said about PVS, which fades and cracks in one season.

When to Choose KGTP Cable

• Construction sites, temporary power supply outdoors, including in winter.
• Connection of welding machines, compressors, pumps, crushers, machine tools with vibration.
• Laying on the ground, through passages, in places with mechanical impacts.
• Operation in an oily and chemically aggressive environment: car repair shops, oil depots, production workshops.
• Ship and port networks, where the requirements for flexibility and resistance to salt fog are high.

When to Choose PVS Wire

• Manufacture of extension cords and portable leads for household use.
• Connection of household electrical appliances: washing machines, dishwashers, air conditioners.
• Internal connections in warm dry rooms where there is no risk of mechanical damage.
• Chandeliers, wall lamps, table lamps, office equipment — wherever the aesthetics of the white sheath is important.
• Budget savings in the absence of strict requirements for frost resistance and oil and petrol resistance.

Typical Mistakes in Selection and Connection

• Using PVS in an extension cord for outdoor work in winter. The sheath cracks, exposing the conductors, creating a risk of short circuit.
• Laying PVS on the ground at a construction site. A stone or a caterpillar easily damages the thin PVC sheath.
• Connecting a welding machine with PVS 3×2.5 wire. The current and temperature exceed the permissible values, and the insulation melts.
• Replacing KGTP with PVS in a machine tool with vibration. PVC does not withstand constant bending, and the conductors break.
• Ignoring the marking: KGTP is produced according to GOST 24334-80, PVS — according to GOST 7399-97. Buying a cable without a passport is fraught with unpredictable characteristics.
• Using KGTP in household lamps unnecessarily. It is stiffer, heavier and more expensive than PVS, and the aesthetics of black rubber is not always appropriate in the interior.

Frequently Asked Questions

How are KGTP and PVS deciphered?

KGTP — flexible cable, tropical version, with rubber insulation and sheath. PVS — wire with vinyl insulation and sheath, connecting. The difference is in the materials and purpose.

How does KGTP differ from PVS in frost resistance?

KGTP retains flexibility down to –40 °C, PVS — only down to –25 °C. KGTP is needed for outdoor winter work.

Can PVS be used outdoors?

Only inside protective ducts and at above-zero temperatures. Under direct sun, the PVC sheath quickly degrades, and in frost it cracks.

What is better for a welding machine: KGTP or PVS?

Definitely KGTP. It is designed for high currents, resistance to sparks and mechanical damage. PVS is not intended for welding.

Which wire withstands a greater load: KGTP or PVS?

At the same cross-section, the load capacity is close, but KGTP tolerates overloads better thanks to the heat-resistant rubber insulation. The rated voltage of KGTP is higher.

What is the service life of these conductors?

PVS serves at least 6 years with periodic bending, KGTP — at least 4 years in a mobile state, but in fixed installation KGTP can serve up to 20 years.

Conclusion

KGTP and PVS are two different worlds of flexible conductors. PVS is home, warmth, simplicity and a low price. KGTP is profession, outdoors, frost, oils and mechanical loads. Replacing one with the other in unsuitable conditions leads to rapid failure and potential danger. When choosing, one starts from the place of operation and the nature of the load: for home — PVS, for construction and production — KGTP. A correctly selected conductor serves long and safely.