Heating cables

Electrical trace heating refers to heating tapes or heating cables for heating pipelines, tanks, containers, open spaces, gutters, and floors, among other things. The tapes or cables are used for frost protection or to keep the temperature of viscous media constant, for example.

The VdS prescribes a redundant trace heating design for sprinkler systems. The control cabinet design must also comply with VdS specifications.

Polymer-insulated heating conductors (single-core plastic cable) and mineral-insulated heating conductors with a metallic outer sheath for high temperatures and high outputs.

Heating tapes: Flat design consisting of two conductors, whereby the actual heating element is usually located between the conductors. Most heating tapes are referred to as self-regulated or self-limiting. Heating cables: round design, usually with fixed heating output and a single current-carrying conductor (serial design).

Self-regulating heating tapes (sometimes referred to as self-limiting heating tapes) and resistance heating cables with a fixed resistance value per metre.

These terms can be used synonymously. Each manufacturer has its own naming conventions, even if the technology is the same.

We distinguish between the simple rubber outer sheath (thermoplastic) and the higher-quality fluoropolymer outer sheath, which is more suitable for use in chemical environments, for example.

This is usually a single-core conductor that heats up due to its specific resistance. The following designs are common: Plastic outer sheath (single-core plastic cable), i.e. polymer-insulated, and mineral-insulated heating conductors, i.e. with a metallic outer sheath for high temperatures.

Yes, at least for temperature-critical applications. Even if the heating tapes are self-limiting with regard to their power output, it is usually impossible to maintain a precise temperature. Without a controller, the tape will eventually settle on an equilibrium temperature – which may be significantly higher than the desired temperature.

The heating element is made of a special plastic containing carbon particles. These are embedded between the two parallel copper conductors and form the current paths. When the temperature rises, the plastic expands, thereby causing the carbon particles to move away from each other. This interrupts the current paths, and the heating cable heats less. As soon as the heating cable cools down, the plastic particles contract again, and the current paths are restored, thus causing the heating cable to produce more heat. The self-limiting property of the heating cable causes it to react to temperature fluctuations at any point in the pipe system.

Yes, halogen-free and low-smoke heating tapes are available.

The maximum temperature in the heating cable depends on the type of heating cable or heating tape, as well as various project and environmental parameters. Depending on the type and application, the maximum temperature range for self-regulating heating conductors is between 65°C and 260°C. Polymer-insulated fixed resistor cables can be used up to a max. temperature of 260°C. For mineral-insulated heating cables, this increases to up to 800°C.

The maximum operating temperature for electrical heating tapes depends on the heating tape type and manufacturer. Heating tapes are usually available for different temperature ranges. However, in addition to considering the holding temperature, you should also keep in mind the maximum process-side temperature to which the heating tape is exposed. The limits of the technology are currently in excess of 200°C (with the heating tape switched on) and approx. 260°C (with the heating tape switched off).

Yes, electrical trace heating can heat up a medium under certain conditions. Heating tape has a limited power output, which means it is generally only able to heat empty pipes or containers. If there is sufficient time available, however, a stagnant (non-flowing) medium can be partially heated.

There are various technologies and cables available on the market. To ensure the right product is selected for your application, a case-by-case consideration of the project conditions (e.g. ambient temperature, insulation, pipe diameter or container size, explosive atmosphere, etc.) is required. A complex design carried out by a specialist company is generally what you need here.