In some applications, the insulating material of cables is exposed to extreme temperatures. In automotive technology, for example, engine cable harnesses and transmission connections must withstand temperatures of well over 100 °C.
Cable manufacturers have divided the cables for these stresses into temperature classes up to 150 °C. Various insulating materials can withstand these temperature stresses, including polyvinyl chloride( PVC), polypropylene( PP) and crosslinked polyethylene (XLPE). The latter has the DIN/VDE designation 2X, can withstand mechanical stress and overloads, and can be used at temperatures of up to 150 °C.