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XLPE insulation for cables

XLPE is the abbreviation of cross-linked polyethylene. In this type of cable stranded aluminum or copper conductor is screened in the form of semiconducting extrusion. Due to which it provides a smooth conducting surface. It also resists the formation of cavities at the conductor surface. It is the form of a cross-link poly-phone.

The insulation is done with high pressure and temperature. Due to which it is widely used. It has remarkable moisture resistance and high chemical resistance. The property of high thermal insulation makes it more suitable to use in both high voltage & temperature conditions. In this article, we will discuss some basic properties, uses, and applications of XLPE insulation.

Properties of XLPE Insulation

The XLPE insulation has endless properties and applications in every industry. In which industry where it is utilized, it takes advantage of its unique properties over other types of cables. We are including some basic properties and advantages in this topic.

• The cross-linking makes and XLPE make it more strong and it the low-temperature impact strength, Environmental stress cracking and abrasion resistance are increased.
• The XLPE insulation has up to the mark thermal properties, and it does not melt even at 120-degree centigrade temperature.
• It has excellent moisture & flame resistance.
• It has excellent dielectric strength, and a low dissipation factor for all frequencies, which make it an ideal insulator.
• The weight of XLPE insulation cable is very less, which makes it more comfortable to use.
• The joining of XLPE cable is less time-consuming than any other conventional cable.

Different types of XLPE insulation Cable

Variety types of XLPE cables are in use nowadays. This contains Automotive wire(GXL), Building Wire (XHHW), Control Cables, Power Cables, and direct burial cables.

Advantages of XLPE Cables

XLPE cables have superior electrical properties. The XLPE insulated cables have higher current carrying capacity and overloading capacity than PVC cables.

• XLPE cables are an ideal solution for high voltage transmission. During the process of transmission where using OHTL is not possible like in cities, no effect on the effectiveness or hindrance occurs.
• The up to the mark mechanical and chemical properties it has amazing moisture, chemical, and oil resistance. It offers greater tensile strength, elongation, and impact resistance.
• During installation, maintenance, and repair of piping systems and networks saves a lot of time and cost.
• For XLPE insulation water tree resistance is another benefit of LV and MV cables over PE insulation.
• Cables insulated with XLPE has current ampacity greater than the same size cable with PVC insulation. This is so clear in the below 2 tables for same sized aluminum cables. The first table is PVC while the second is XLPE.

Disadvantages of XLPE Cable

• The 11kV underground distribution of XLPE cable is costly as compared to the paper-insulated aluminum-sheathed cable.
• Although some XLPE polymers are water-tree resistant however there is still a risk of medium sensitivity to water treeing.

The difference between XLPE cable and PVC cable

1. XLPE cables have higher current carrying capacity than PVC cables of the same size because XLPE cables have higher working maximum temperature than PVC. (90ºC for XLPE while 70ºC for PVC).
2. XLPE cables have higher maximum short circuit temperature than PVC cables.
3. XLPE cables have longer life time than PVC ones.
4. PVC cables price is less than XLPE ones.
5. XLPE has no chlorine  which causes toxic gases production in case of fire. So XLPE insulated Cable is environment friendly compared with PVC Cable.

IS XLPE cable armored?

This is one of the FAQ about XLPE cable. The direct answer of this one is that the XLPE insulation is different of cable armor. The armor is a mechanical protection around the cable. Its made of steel and is represented as SWA (steel wire armor) or STA (steel tap armor). So the cable could be PVC armored and could be XLPE not armored.

Is XLPE water proof?

The XLPE insulated MV cables are manufactured with longitudinally waterproof shielding to prevent moisture penetration and to extend life time.

xlpe insulation temperature rating

XLPE cable has  working maximum temperature of 90ºC and maximum emergency rating up to 140ºC and short circuit conductor rating of 250ºC.