Nelson™ Heat Trace Type CLT Self-Regulating Heaters

Nelson

Nelson™ Heat Trace Type CLT Self-Regulating Heaters

Nelson

Nelson™ Heat Trace CLT Series heating cables provide an industrial and commercial-grade solution for maintaining fluid flow under low ambient conditions. These self-regulating, cut-to-length cables are normally installed in commercial and light industrial applications, to maintain pipe temperature and/or prevent freezing in ambient temperatures down to -40 °C/-40 °F. CLT Series heating cables are available in 120 and 240 voltages and are designed for use in ordinary (unclassified) locations. Typical applications for this product are freeze protection and low watt density process temperature systems such as product pipelines, fire protection, process water and dust suppression systems.

Specifications

Certifications and Compliances
UL Listed, CSA Certified: Ordinary (Unclassified) Locations
Maintain Temperature
65 °C (150 °F)
Maximum Continuous Exposure Temperature
65 °C (150 °F) continuous power on
Maximum Intermittent Exposure Temperature
85 °C (185 °F) 1000 hours cumulative exposure
Bus Wire Size
18AWG Copper Conductors
Minimum Installation Temperature
-40 °C (-40 °F)
Minimum Bend Radius
12.0 mm (0.50 in) at -40 °C (-40 °F)
Dimensions
6.7 mm x 11.1 mm (0.264 in x 0.437 in)
Accessories
Connection kits, thermostats, contactors, junction boxes, tape, warning signs, custom control, and monitoring and power panels are available. See catalog pages for details

Features

  • Type CLT self-regulating heater cable is a parallel circuit electric heater strip. An irradiation cross-linked conductive polymer core material is extruded over the multi-stranded, tin-plated, 18-gauge copper bus wires. The conductive core material increases or decreases its heat output in response to temperature changes. Two jackets provide extra dielectric strength, moisture resistance, and protection from impact and abrasion damage. A thermoplastic elastomer overjacket is then extruded over the inner jacket. A tinned copper braid is installed over the second jacket, providing a continuous ground path. A UV stabilized polyolefin overjacket is provided to cover the braid for wet applications.
  • Operating principle: The parallel bus wires apply voltage along the entire length of the heater cable. The conductive core provides a continuous parallel heating element permitting the cable to be cut to any length in the field with no dead or cold zones developing. The heater cable derives its self-regulating characteristic from the inherent properties of the conductive core material. As the core material temperature increases, the number of conductive paths in the core material decreases, automatically decreasing the heat output. As the temperature decreases, the number of conductive paths increases, causing the heat output to increase. This occurs at every point along the length of the cable, adjusting the power output to the varying conditions along the pipe. The self-regulating effect allows the cable to be overlapped without creating hot spots or burnout. As the cable self-regulates its heat output, it provides for the efficient use of electric power, producing heat only when and where it is needed.
  • Voltage ratings: 240 Vac products are suitable for use on supply voltages of 208-277 Vac. See catalog pages for details.

Documents & Drawings