Detailed Description
What Is Trace Heating Cable?
An electric trace heating cable (also called heat tracing, heat tape, or heating tape) is a flexible cable that converts electrical energy into heat along its entire length to compensate for heat losses from pipes, tanks, roofs, and other surfaces to the surrounding environment. Unlike a conventional power cable — which is designed to deliver electrical energy from A to B with minimum loss — a heating cable is designed to dissipate electrical energy as heat (I²R loss in a resistive heating element) at a controlled power per unit length, distributed uniformly along the cable.
Trace heating replaces or supplements conventional thermal insulation. A pipe with 50 mm of mineral wool insulation loses approximately 8–12 W/m of heat at a 40°C temperature difference between the pipe contents and the ambient air. Without trace heating, water in an unheated attic pipe at -10°C ambient will freeze within hours regardless of the insulation thickness — because insulation only slows heat loss; it does not add heat. A 10 W/m trace heating cable installed on the pipe surface under the insulation adds exactly the heat that is lost, maintaining the pipe at a safe temperature above freezing.
Self-Regulating vs Constant Wattage — How They Work
| Parameter | Self-Regulating (PTC) | Constant Wattage |
|---|---|---|
| Heating element | Carbon-black-loaded polymer matrix between two bus wires | Nichrome resistance wire (zone type: spiralled around bus wires; series type: continuous single wire) |
| Temperature response | Power output decreases as temperature rises — the polymer matrix resistance increases per the PTC effect | Power output is fixed regardless of temperature |
| Self-regulation | Yes — the cable adjusts its heat output to match the local heat loss; if a section is covered by snow (insulated), that section's temperature rises and its power output drops, preventing overheating | No — the cable delivers constant power; it must be controlled by a thermostat to match the heat demand and prevent overheating |
| Overlap tolerance | Can be overlapped — if the cable crosses itself, the overlapped section warms up, its resistance rises, and its power output drops, preventing hotspot formation | Cannot be overlapped — overlapping a constant wattage cable creates a hotspot because both cable sections deliver full power at the overlap point, doubling the heat flux and potentially overheating the cable |
| Cut-to-length on site | Yes — the heating matrix between the bus wires acts as a continuous resistive strip; cutting the cable anywhere between bus wires creates a functional heating section | Zone type: cut at marked zone intervals only (typically 1 m); series type: factory-cut only — the total resistance determines the heat output and cannot be changed on site |
| Circuit length flexibility | Yes — the cable can be shortened or extended (within the maximum circuit length limit) to match the pipe length | Zone type: limited to integer multiples of the zone length; series type: fixed factory length |
| Typical applications | Pipe freeze protection, roof de-icing, commercial hot water maintenance | Long pipeline industrial trace heating, tank heating, process temperature maintenance where constant heat output is required and the thermostat provides control |
| Cost per meter | Higher — more complex manufacturing (extruding the heating matrix) | Lower — simpler construction |
| Thermostat required | Recommended (energy saving) but not mandatory — the self-regulation provides inherent overheat protection at moderate ambient temperatures | Mandatory — the thermostat is the only overheat protection |
Self-regulating cable dominates the commercial and residential trace heating market because of its safety advantage: it cannot overheat itself if overlapped, covered, or buried in insulation. For industrial applications where the process temperature must be maintained precisely and the installation conditions are controlled (no overlap risk, thermostat installed), constant wattage cable is a cost-effective alternative.
Why Choose Yichi Trace Heating Cables
- IEC 60800 / IEEE 515 compliant — tested for trace heating safety: The cable is type-tested for the full trace heating duty cycle including cold-start current surge, thermal ageing at rated temperature, mechanical crush and impact resistance, and earth braid continuity. Trace heating cable is a safety-critical product — a failed cable in an attic can cause a frozen pipe burst costing thousands in water damage; a failed cable in a chemical plant can cause a process fluid to solidify, shutting down production
- Self-regulating and constant wattage technologies — select the right cable for the application: Yichi manufactures both technologies. For most commercial and residential trace heating, self-regulating cable with its inherent safety and cut-to-length convenience is recommended. For industrial long-pipeline and process applications, constant wattage cable with its predictable heat output and lower cost per meter is available
- Fluoropolymer high-temperature option to 200°C: For industrial process pipe trace heating where the pipe temperature exceeds 65°C (steam-traced replacement, high-temperature process maintenance), the fluoropolymer-jacketed self-regulating cable provides reliable heat tracing at temperatures that would degrade a polyolefin or TPE jacket within months
- Tinned copper bus wire and earth braid: Both are tinned — because trace heating cables are installed in environments where condensation and moisture are present (pipe chases, attics, roof edges). Bare copper in these environments corrodes, increasing the bus wire resistance and reducing the heating cable's power output over time. Tinned copper maintains stable electrical characteristics for the rated service life
- Cold lead factory-jointed and sealed: The transition from the non-heating cold lead to the heating cable is the most critical joint in the installation — if water enters this joint (from condensation, rain, or pipe leaks), it can cause earth leakage, circuit breaker tripping, and heating failure. The Yichi cold lead connection is over-moulded and rated IP67 for wet locations
- Application sizing support: Provide the pipe diameter, insulation type and thickness, minimum ambient temperature, required maintain temperature, and the pipe material (metal or plastic) — we calculate the heat loss per meter per IEC 62395 (industrial trace heating design) or IEEE 515 and recommend the cable power output, circuit length, and thermostat set point