Longline (HTS1F) is a series resistance, single conductor heating cable . It is supplied in multiples of three cables for configuring into a 3 phase heating system. It is used for freeze protection or process temperature maintenance of long pipelines up to 5km, in safe or hazardous areas. A typical application is the temperature maintenance of crude or fuel oils in above ground or buried transfer lines. Longline (HTS1F) minimises the number of electrical supplies needed and so minimises supply cabling and distribution equipment costs. Circuits are often fed at the pipe ends only.
The number of heating cables and their conductor size is varied to produce the desired heat output for the circuit length required. The Longline (HTS1F) heating cables are connected directly to the 3 phase mains voltage or to a step-up transformer.