What is difference between PVC cable & XLPE cable?

Answer Posted / paul abernathy

Hello All-

While all of the answers are for the most part technically correct they do not answer the fundamental question presented. The differences in PVC versus XLPE is that PVC can be extruded, melted and re-extruded (or formed as Thermoplastic compound) while XLPE is a thermoset (or setting) which means it is not capable or regaining it's thermal melting point to be reconfigured or re-extruded. Due to these properties (melting is a result of heat) Thermoset is by it's nature prone to better results in higher temperature environments.

At the end of the day, insulation is insulation and both Thermoplastic or Thermoset have temperature ratings (in terms of wire/cable) at 90 °C . However, the thermoset properties of thermal breakdown are better in this case. Typical building wiring uses Thermoplastic (THHN/THWN-2) which is a PVC Thermoplastic product. However, the use of Thermoset insulation like XHHW (notice the "X") does have a higher property for potential temperature values even if the baseline for NEC use is 90 °C . For example, in an emergency situation the XLPE insulation threshold can reach up to 140 °C depending on the various standards employed.

Crosslinking improves the elevated-temperature properties of the base polymer. Adequate strength to 120–150 °C is maintained by reducing creep, the tendency to flow. Chemical resistance is enhanced by resisting dissolution. Low temperature properties are improved. Impact and tensile strength, scratch resistance, and resistance to brittle fracture are enhanced.

They key is this in terms of product manufacturing, the thermoplastic insulation is always less mils than the thermoset insulation and thermoplastic tends to have (not required) a nylon outer coating to the insulation which adds some protective value which is gained in XLPE without the nylon due to an increased mils insulation value.

Hope this was helpful.

Is This Answer Correct ?    52 Yes 4 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

transformer phasor diagram under load explain it?

1673


what is meant by carrier aided trip protection in transmission line

3313


what & how to check the lightning arrester

1461


Different STANDARDS (BS, IS, IEC etc) gives different informations on CT specification. How they correspons w r t each other (i.e I mean to say BS provides "knee point voltage" but IS does not, then how can i select CT)

1512


What is the settings of distance protection relay in 400 kv line

1196






Define unilateral circuit?

707


What is the maximum operating temperature for a thermoplastic insulated cable?

658


how does the terminal voltage of transmission lines increase when a capacitor is connected???? This happens not only in transmission lines but also in all circuits. How??? When a capacitor is connected in a transmission line, capacitor also takes energy from the same supply. But how is it able to increase the terminal voltage??? Practically What sequence of events happen during increase in voltage???

1620


What do you mean by an instrument transformer?

656


How can we find the breaking capacity of a Load breaker switch (LBS) fed from 11 kv supply??ex:50KA, 26kA etc???detailed step vice answer pls.

1591


what should be the no load current for 3 phase ac motors ranging from 5 kw to 1000kw?

1381


I have a small system with two motors that are running on 380 vac, 60 hz. These motors are expensive and I usally get them from Brazil. I am adding another motor to the system, but I want to purchase a 480 vac, 60 hz motor to use. It will be on a VFD that is rated fro 380 thru 480. Is this posible and will I have to use a larger motor and derate it?

1534


what is the most permissible winding temp when we conducting a generator load test?(condition no load)

1233


how to calculte capacitor range for single phase induction motors??pls tel

1622


Draw the circuit of clapp oscillator?

677