The changing face of power cable

Woven textile covered RHW class power cable has long been the mainstay of US telephone companies. It is rugged with good cold flow and abrasion characteristics. After nearly a century of manufacture and deployment, this genre of cable is now becoming obsolete. Textile RHW is expensive and a declining base of wire and cable manufacturers still make the product. Many modern thermoplastic insulation types hold up well and have the necessary characteristics to carve a niche for themselves in the network. This paper describes tests that Bell Atlantic used to see how a number of commercially available cable types stacked up against woven textile covered RHW cable. The tests determined the cold flow and cut-through strength of these cables using cable samples of several vendors and cables of different stranding types. The paper also explores a number of case studies of power cable insulation failure that resulted in arcing faults to the grounded cable tray system. Finally, this paper addresses the rationale for abandoning a long-held policy that required the use of tinned copper conductors in favor of simple copper.