Electric heating systems for various objects are quite in demand today. It is fashionable to use them both indoors and outdoors. Self-regulating heating cable is of particular interest. It is less demanding on the installation process and consumes less energy. Its design and principles of use are different from conventional resistive cables.
Content
- general characteristics
- Wire construction
- Main advantages
- Choosing the right cable
- Product cost
- Consumer assessment
general characteristics
Self-heating cables are very similar in appearance to ordinary cables, but only slightly flattened. This is due to their design. This shape allows you to fit more closely to the heated surface.
Most often, these products are used to heat pipes, tanks, drains and roof gutters. Systems are offered that are intended for the arrangement of indoor heating, as well as for outdoor installation in the ground or screed. They are laid on the steps or the roadway.
The range of application of such products is extremely wide. The advantage of the cable is the change in the intensity of heating and energy consumption depending on the ambient temperature. Therefore, such a system does not need a thermostat: it adjusts itself to existing conditions.
Wire construction
The heating cable has a special design. In it, between two conductive cores, there is a matrix made of a special polymer material, which is made on the basis of carbon.
When the temperature in a certain area decreases, the electrical conductivity of the product increases, as does the heating itself. If it is quite warm around the heating cable, the material changes its properties and begins to restrain the flow of electricity, respectively, while the heating decreases.
The inner structure is protected by several shells. A metal shield is necessary for grounding and protecting the heating elements from mechanical damage. The PVC upper shell also increases the durability of the product. The strength class determines the conditions in which the system can be used.
Main advantages
The self-regulating heating wire has a number of advantages. Compared to resistive products, it is easier to operate. He is not afraid of local overheating and does not need to maintain the same temperature along the length.
It should also be noted that the system is not afraid of power surges. Unlike a constant heating wire, it can be crossed. This is especially important when arranging heating of piping systems and their valves.
Due to the design features, the product can be cut into small pieces. The minimum length is 10-15 cm. Having paid attention to the scope of their application, we can say that in the near future self-regulating systems can replace resistive ones.
Choosing the right cable
For installation inside the pipe and outside, low-temperature samples are used, which are heated to a maximum of +60 ° C. When calculating a heating cable, you should focus on the following indicators:
- in the most severe weather conditions, choose a 30 W cable;
- in the case of an internal location when pipes pass underground, the optimal power will be 5 W per linear meter;
- outdoor location - depending on the depth of occurrence, you can use samples with a power of 10-15 W / m;
- any position with outdoor pipes - choose a thin heating cable with a power of 20-30 watts.
Low-temperature self-heating cable to protect the pipeline from freezing has a small thickness and is flexible, so that it can be wrapped around water pipes without problems.
The length of the cable is an arbitrary indicator, but there are still some restrictions. The maximum recommended length is 80-100 meters, the minimum is 20-30 cm. As for the bending radius, it is 6 diameters or more. When choosing a self-regulating heating cable, remember that there are two types:
- technical purpose - used for heating water pipes from the outside;
- with safe insulation - it can be laid inside the pipe, as it uses safe fluorine-containing insulation.
When buying this or that sample, you should check with the seller about the possibility of using a heating cable inside the water supply pipe. Also on sale are universal heating cables with silicone insulation, suitable for heating pipes and capable of working as part of underfloor heating.
Product cost
To purchase a system of this type, you will have to spend more money than buying a regular cable. But during operation, the price pays for itself pretty quickly.
The cost of a self-heating cable depends on the cross-section, power and manufacturer. The most expensive are products made in Denmark - their cost can reach 700 rubles. per 1 m. Domestic manufacturers produce systems, the starting price of which is 100 p. for 1 m.
The longer the wire is purchased, the cheaper each running meter will cost. This must be considered before purchasing a product.
Consumer assessment
There are several brands of products that are most popular today. They have the best consumer reviews in the modern market.. These include:
- Raychem;
- Ensto;
- Devi;
- Lavita.
Inside the pipeline, the most commonly used products are Ensto (20 W / m) and Lavita (16 W / m). Raychem products (10 W / m) are installed outside the communications. The Danish company Devi produces a cable for a wide range of applications (9 W / m), but its cost is the highest. The most reasonable price for Ensto and Lavita wires. Also, consumers noted the high quality of these products.
The Finnish company Ensto is not inferior to Devi in terms of durability, but these products will cost the buyer much cheaper. Therefore, many consumers choose products of this particular brand.
Having studied the device of self-regulating cables, you can use them correctly in everyday life. Their installation is quite easy to do on your own. The choice depends on the power of the product and the conditions of its use. It is a very efficient and durable system. It will serve its owners for many years, subject to proper operation and installation.
