CABLE INSULATION
ADVANTAGES & DISADVANTAGES | Material | Advantages | Disadvantages | Max Operating Temperature |
| PVC | Cheap, Durable, Widely available | Highest dielectric losses, Melts at high temperatures, Contains halogens | 70oC for general purpose 85oC for heat resisting purpose |
| PE | Lowest dielectric losses, High initial dielectric strength | Highly sensitive to water treeing, Material breaks down at high temperatures | |
| XLPE | Low dielectric losses, Improved material properties at high temperatures | Does not melt but thermal expansion occurs, Medium sensitivity to water treeing (although some XLPE polymers are water-tree resistant) | 90oC |
| EPR | Increased flexibility, Reduced thermal expansion (relative to XLPE), Low sensitivity to water treeing | Medium-High dielectric losses, Requires inorganic filler / additive | 90oC |
| Paper / Oil | Low-Medium dielectric losses, Not harmed by DC testing, Known history of reliability | High weight, High cost, Requires hydraulic pressure / pumps for insulating fluid, Difficult to repair, Degrades with moisture | 70oC |
Mainly above 6 sq mm cables are called power cables but it depends upon the use of cable. For PVC power cables we use IS:1554 and for XLPE power cables we use IS:7098 and for Rubber based power cables we use IS:9968 and other relevant specifications. Power cables are defined by voltage grade and nominal cross sectional area.