There are two different types of heating cables: self-regulating and constant wattage. These cables, also known as “heat trace” or "heat tapes,” are used for freeze protection solution. While both achieve the same goal, their construction, operation, and installation differ.
Self-Regulating Cable
Self-Regulating Cable
{{widget type="Magento\Catalog\Block\Category\Widget\Link" anchor_text="Self-Regulating" template="category/widget/link/link_inline.phtml" id_path="category/29"}} cable adjusts it's heat output based on the surrounding temperature. This cable consist of two bus wires with a semiconductive core. Over the core, there are additional layers of insulation, a braided mesh for grounding, and often a polymer over jacket for moisture protection.
As the ambient temperature decreases the core becomes more conductive and allows the cable to generate heat. As the ambient temperature or the temperature of the item being heated rises, the core becomes less conductive and produces less heat.
Self-Regulating Cable Advantages:
- Automatically adjusts heat output
- No temperature controller required
- Safe for overlapping installations
- Ideal for long runs and freeze-protection applications (e.g., roof & gutter deicing, fire suppression piping)
Constant Wattage Cable
Constant Wattage Cable
{{widget type="Magento\Catalog\Block\Category\Widget\Link" anchor_text="Constant Wattage" template="category/widget/link/link_inline.phtml" id_path="category/185"}} cable also has two conductive heating wires, as well as layers of insulation and over jacketing. The real difference in its construction, which impacts operation, in that there is no conductive core that reacts to changes in the ambient temperature.
When power is applied to the cable, heat is generated based on the resistance of the wire. Without a thermostat or temperature controller the cable will continue to generate heat until the temperature exceeds the maximum exposure temperature. For this reason, constant wattage cable must have a device to regulate the power to the cable and it cannot be overlapped when installed.
Constant Wattage Cable Advantages:
- Precise temperature control for process heating applications
- Maintains shape for tight wrapping
- Suitable for long runs and emergency de-icing
- Often used in floor heating systems
The Best Heat Trace for Freeze Protection
Both cable types are available in various power ratings (3 to 20 watts) and can be cut to length during installation. Choosing the right option depends on the application:
| APPLICATION | SELF-REGULATING | CONSTANT WATTAGE |
| Roof & Gutter De-icing | Better | Good |
| Freeze Protection for Pipes | Better | Good |
| Fire Suppression Piping | Better | Not Allowed |
| Heating Valves | Better | Good |
| Heating Floors | Good | Better |
| Warming for Vscosity | Good | Better |
| Energy Efficiency | Better | Good |
| Hazardous-Area | Good | Good |
| Installation Requiring Overlap | Better | Cannot Overlap |
| Tight Wrapping on Small Objects | Good | Better |
Determining which cable is better is best decided by the application. Cost may also be a consideration in that constant watt is typically more expensive than self-regulating cable. Additionally, while use of a temperature controller is optional with a self-regulating system, it is required for a constant watt system.
Do you still have questions? Briskheat has answers! We stock both self-regulating and constant watt cable in a variety of styles and wattages. Your BriskHeat Account Executive or Local Distributor are trained to assist you with selecting the right cable and accessories for your heat trace application.