Method for installing heat shrink cover, electric heating system and installation system

Abstract

The present invention relates to a method for installing a heat shrink cover around a component to be covered. In particular, a method for installing a heat shrink cover around a component to be covered by an electric heating system is provided, the electric heating system comprising an electric heating unit and an electronic control unit connected to the electric heating unit, the method comprising the following steps: attaching the electric heating unit to the outer surface of the heat shrink cover; arranging the heat shrink cover around the component to be covered; retrieving at least one setting parameter of the heat shrink cover and / or the component to be covered, and generating a setting value indicating the at least one setting parameter; in an actuation step, actuating the electric heating unit to provide heat for thermally restoring the heat shrink cover, wherein the actuation step is performed in response to the setting value.

Description

Technical Field

[0001] The invention relates to a method for installing a heat shrink cover around a component to be covered. In particular, the invention can be used to install medium voltage (MV) joint bodies of 12 to 42 kV, but can also be used to advantage for covering other components and for other voltage levels. In particular, the invention can be used to install heat shrink joint bodies and re-sleeve sleeves, and in principle all types of heat shrink sleeves, such as terminal and cover sleeves, and molded products such as sheds, splits, boots and caps. The invention also relates to an electric heating system and a mounting system for flameless installation of a heat shrink cover. Background Art

[0002] Most existing MV joints consist of a heat shrink joint body with a mastic, stress control sleeve or patch underneath. On the outside of the heat shrink body, a conductive mesh is applied or a socket is positioned, and the cable's shield or tape shield is connected from one end of the joint to the other. Finally, the entire connection area is usually covered by a heat shrink outer protective sleeve, the so-called resleeve sleeve.

[0003] Heat shrink components in the sense of the present invention relate to articles made of a material which shrinks from an expanded state to a contracted state of much smaller diameter by the application of sufficient heat.Heat shrink components are widely used as connector sleeves or other cable accessories.

[0004] The present invention utilizes heat-recoverable articles (independently dimensionally thermally unstable articles) as heat shrink layers. Generally speaking, such articles are made of materials that can impart elastic or plastic memory properties to them, which are heated to a certain temperature and deformed, for example, deformed to a configuration different from its normal configuration under internal pressure, and then cooled while being maintained under pressure. If the article is made of a completely or partially crystalline material, at least partially cross-linked in the amorphous region, and deformed at a temperature at or above the crystalline melting point of the material, the article will have elastic memory. Articles with elastic memory will not return to their original configuration until they are heated again to at least their crystalline melting temperature. If the article is made of an amorphous material, it is heated to a temperature at which the article can be deformed by pressure, and then the deformed article has the characteristics of plastic memory. Of course, the heat shrink layer can be made of any suitable material, which is known to those skilled in the art. In addition, the present invention also includes a multilayer structure that additionally includes elastic and / or electrically semiconductive and conductive layers.

[0005] The heat shrink cover installed according to the present invention is used for voltages above about 1 kV. In particular, in the context of the present invention, the term high voltage is intended to include the usual nominal voltage ranges for power transmission, namely medium voltage (MV, about 3 kV to about 72 kV), high voltage (HV, about 72 kV to about 245 kV) and extra-high voltage (currently up to about 500 kV). Of course, higher voltages may also be considered in the future. These voltages may be direct current (DC) or alternating current (AC) voltages. In the following, the term "high voltage cable" is intended to mean a cable suitable for carrying a current greater than about 1 A at a voltage above about 1 kV. Therefore, the term "high voltage accessory" is intended to mean equipment suitable for interconnecting high voltage facilities and / or high voltage cables. In particular, the high voltage accessory may be a terminal or a cable connector.

[0006] The invention is also applicable to the so-called "low voltage (LV)" range, which relates to voltages below 1 kV.The principles of the invention may further be applied to heat shrink products for electronic applications, plumbing and building applications and the like.

[0007] The expression "sleeve" according to the invention is intended to mean straight tubular sleeves as well as differently shaped covers for branch joints, elbows, bends, splits, surrounds, sheds and the like.

[0008] For installing heat shrink products for LV, MV and HV applications, an open flame is usually used, such as a gas torch. However, the use of an open flame is disadvantageous from a work safety point of view. Furthermore, it is desirable to reduce the energy and time required for installing the product. In some cases, it is also desirable to reduce the heat generated during the installation process. One main aim is to reduce the influence of the joint technology on the heat shrink installation result. Automated installation is highly desirable. Therefore, it is desirable to use energy sources other than open flames, preferably electrical energy. In particular, it is desirable that the joint body and the re-sleeving sleeve can be installed flamelessly in one process without further interaction of the cable joint.

[0009] For example, from published European patent application EP 3 624 288 A1 a method for installing a heat shrink cover around a component to be covered is known, in which an electric heating system is used instead of an open flame. Although these known electric heating systems have many advantages, the inventors of the present invention surprisingly found that the quality of the heat shrinking process and the final connector arrangement depends to a large extent on the material underneath the parts of the heat shrink cover. In particular, it was found that the thermal conductivity and the temperature of the cables to be connected have a significant influence on the performance and quality of the heat shrinking process.

[0010] As mentioned above, the heat shrink MV joint system has an inner joint body and an outer re-sleeve sleeve. The heater is arranged on the outside of the re-sleeve sleeve, and the joint body is located centrally below and has a short length. The installation of this MV joint system takes place in a trench or manhole, and rarely in a closed environment such as a wind tower or enclosure. Compared to a laboratory environment under controlled temperature conditions, the MV joint system under real conditions is installed in the field where the air temperature is between 0℃ and 45℃. The temperature of the cable is between -10℃ and +60℃. Summary of the invention

[0011] The invention is based on the discovery that the heating sequence must be different according to these temperatures. Moreover, this difference is not just a (linear) extension and reduction of all parts of the time series, but means a more complex variation of the thermal energy over time.

[0012] The object of the present invention is to provide an improved installation method, electric heating system and installation system for installing a heat shrink cover on a component to be covered, which alleviates or overcomes the disadvantages of traditional installation methods and significantly reduces installation time, manufacturing costs and complexity, while ensuring safe covering of the component to be covered, in particular by achieving automated installation that overcomes the reliance on joining technology. Such an automated installation method must fully handle the influence of the substrate to be covered and its condition, in particular its temperature during the installation process, in order to set the correct process parameters.

[0013] This object is achieved by the subject matter of the independent claims. Advantageous embodiments of the invention are the subject matter of the dependent claims.

[0014] The invention is based on the idea that the electrical heating sequence for shrinking a heat shrink cover must be selected in response to at least one of the following parameters, namely component temperature, material and / or geometry of the component to be covered, material and / or geometry of the heat shrink cover and ambient temperature.

[0015] Specifically, the present disclosure provides a method for installing a heat shrink cover around a component to be covered by an electric heating system, the electric heating system comprising an electric heating unit and an electronic control unit connected to the electric heating unit, the method comprising the following steps:

[0016] attaching an electric heating unit to an outer surface of the heat shrink cover;

[0017] Arranging the heat shrinkable cover around the component to be covered;

[0018] Retrieving at least one setting parameter of the heat shrink cover and / or the component to be covered, and generating a setting value indicating the at least one setting parameter;

[0019] In the energizing step, the electric heating unit is energized to provide heat for thermally restoring the heat shrinkable cover, wherein the energizing step is performed in response to a set value.

[0020] By taking into account at least one setting parameter, the adverse effect of the component to be covered acting as a heat sink or, in very hot conditions, as an additional heat source can be compensated and the quality of the connection as well as the time necessary to install the cover can be optimized. Thus, reliably good electrical and sealing properties can be achieved with a short installation time.

[0021] According to another example, retrieving at least one setting parameter comprises measuring the temperature of the part to be covered. In very cold conditions, the metal part of the part to be covered transfers a lot of heat, so the energy delivered by the heating unit must be increased. On the other hand, in very hot conditions (for example in Arabia or Australia), since the high temperature of the part to be covered facilitates the heating process, the heat shrinking time of the cover can be significantly reduced.

[0022] According to another advantageous example, retrieving at least one setting parameter comprises acquiring first configuration data characterizing the component to be covered. The configuration data comprises, for example, dimensions and materials of the cable connection.

[0023] In particular, the component to be covered may be a cable connection, wherein the first configuration data comprises information indicating the cable type and the cable diameter and / or the connector type and / or the sealing material.

[0024] Furthermore, retrieving at least one setting parameter may comprise obtaining second configuration data characterizing the heat shrink cover. In particular, the second configuration data may comprise information indicating a material thickness and / or a material composition of the heat shrink cover. An advantage of this solution is that for each specific type of heat shrink cover, an optimal heating sequence may be applied. Furthermore, special cases where the heat shrink cover comprises more than one part, such as a connector body and a re-sleeve sleeve, may also be considered.

[0025] According to an advantageous example of the present disclosure, the energizing step comprises at least one of a preheating phase, a main heating phase, and a post-heating phase. In particular, the energizing step may comprise at least one of a heating phase, a main heating phase, and a post-heating phase, wherein the heating phase heats the heat shrink cover at least partially to a temperature below the installation temperature, the main heating phase heats the heat shrink cover until it at least partially shrinks, and the post-heating phase introduces further heat energy after the heat shrink cover has at least partially shrunk.

[0026] It was found that the pre-heating period and the post-heating period (also called "stages") should be added to the main heating period, which will also be called the "full" heating period. There are several advantages to using these different stages.

[0027] First, preheating can reduce overall installation time. The joint components are made of thermally insulating materials. Preheating allows the temperature to be raised to levels such as 30°C to 70°C. These temperatures are much lower than the heat shrink installation temperatures of approximately 90°C to 120°C. Therefore, when full heating is performed, it can run faster than starting from ambient or low temperatures.

[0028] Preheating also allows for a more reliable installation at the same temperature, regardless of the temperature of the previously heat-shrunk component.

[0029] An important reason for post-heating is that heat shrink tubing may shrink to a certain extent, but not completely without fully heating the entire material. The result is a reduction in radial pressure on the component to be covered (i.e. the cable). This may result in improper electrical performance or an improper seal. Applying a post-heating stage can help by fully heating the tubing as a whole after some recovery of the tubing and help soften the entire heat shrink material so that it shrinks completely and generates maximum radial pressure after cooling. The length and intensity of the post-heating depends, among other things, on the heat dissipation characteristics of the substrate.

[0030] In some cases, such as specific fitting bodies, heat shrink sleeves are multi-layered, i.e. have an inner elastomer layer that does not require heat to shrink, but is required in order to make good contact with the cable. This is particularly important when the cable temperature is quite low before installation. In other cases, heat shrink sleeves are installed in areas where mastics and other (thermal) fitting materials are applied. These require a certain amount of heat for a certain period of time to soften and flow as required.

[0031] A fundamental reason for pre-heating (and post-heating) is to support the creation of a heat wave from the center to the end of the joint. The reason for this is that the heat shrink tubing should be installed gradually to evacuate air for good electrical performance and / or to avoid air entrapment. The number of heating elements is limited to reduce overall product cost. The width of the heating element is between 50 and 150mm in the area where the joint body is located, and up to 250mm where the seal is formed on the cable jacket.

[0032] Preheating supports a gradual shrinkage of the sleeve despite the large width of the heater. In the course of intensive tests it was found that, despite a heater system with the above-mentioned width, a well-defined cascade of preheating, full heating and postheating as well as a specific time lag between the activation of adjacent heating elements significantly leads to the generation of heat waves and gradual shrinkage. Without this, parts of the joint body are more likely to shrink through sections whose width corresponds to the width of the external heater. The appropriate electrical properties of the installed joint body were measured by reaching different partial discharge levels (i.e. maximum 5pC at 24kV for a 24kV joint). It was found that such good PD results could only be achieved by generating a gradual shrinkage of the joint body.

[0033] According to an advantageous example, the heating unit comprises a plurality of heating sections, which can be controlled by an electronic control unit. These heating sections are also referred to herein as heating elements, and can be formed by integrated interconnected elements or by separate parts. The control unit advantageously controls each heating section individually. Alternatively, the heating sections can also be interconnected to form a group of heating sections that are simultaneously excited. This is conducive to axially symmetrical heating relative to the center of the heat shrink cover. Specifically, the heating section can be excited by being introduced into a current flowing through the heating section conductor, and / or can be excited by a current controlled by retrieved feedback data, which is, for example, the corresponding actual voltage and current value of the heating section and / or data retrieved from a separate sensor element.

[0034] The present disclosure also relates to an electric heating system for installing a heat shrinkable cover around a component to be covered, wherein the electric heating system comprises an electric heating unit and an electronic control unit connected to the electric heating unit, and wherein the electric heating system is operable to perform the method according to the present invention.

[0035] Advantageously, the electric heating system comprises a temperature sensor for measuring the temperature of the component to be covered and / or the temperature of the air in the environment of the component to be covered and / or the temperature of the heat shrink cover. Such a temperature sensor can, for example, be integrated into a probe which is connected to the control unit via a cable or a wireless connection. By accurately determining the actual temperature of the component to be covered, heat absorption effects due to low component temperatures can be compensated. Furthermore, in the case of high component temperatures, the time required for mounting the cover can be kept as short as possible.

[0036] According to another example, the electric heating system includes an input device for inputting at least one setting parameter of the heat shrink cover and / or the part to be covered. For example, the input device may include an input device for inputting an ID code of the heat shrink cover, and include a barcode reader, an RFID reader, a QR code reader, a wireless communication interface and / or a manual input interface and / or a wired connection to a chip located at the heat shrink cover. The ID code may include a product identification and / or a product application range and / or a product attribute value, such as the resistance of the heating element. According to one option, the heat shrink cover may have an integrated chip, which may be connected to the control unit like a heater. In this case, the control unit may read the data on the integrated chip. The reading action of the cable connector is not required, which not only saves time but also avoids the root cause of incorrect data input.

[0037] Finally, the present disclosure provides a mounting system, comprising:

[0038] a mounting kit having a heat shrink cover on which an electric heating unit is mounted, and the mounting kit having the electric heating unit, and

[0039] An electronic control unit is used to control the electric heating unit to provide heat during a heat recovery step of heat-recovering the heat-shrinkable cover according to the method of the present invention.

[0040] The present invention can advantageously be used with a multi-part heat shrink cover comprising at least one outer sleeve and at least one inner sleeve. Before starting the installation process, the at least one outer sleeve and the at least one inner heat shrink sleeve can be at least partially in thermal contact. This can be achieved by preheat shrinking the outer heat shrink sleeve in the factory, or by positioning a pre-stretched elastic sleeve on the inner heat shrink sleeve, or by wrapping film, etc. In principle, this can be done on site, not just in the factory. Alternatively, the at least one outer sleeve and the at least one inner heat shrink sleeve are not initially in thermal contact, i.e. by being separate components, which means that they can move freely before the heat shrink installation process.

[0041] The at least one outer sleeve preferably comprises a further heat shrink sleeve, but may also be an elastic cold shrink sleeve, or a plastic or metal film / sleeve / mesh / net or the like.

[0042] Furthermore, on the outer surface of the outermost sleeve, additional objects can be placed, i.e. protecting the surface from the heat source. These can be additional (thin-walled, low-cost) heat shrink sleeves and / or plastic or metal films / meshes etc. The effects of the heat source can be mechanical damage to the surface (dents, cracks, blisters, chemical degradation) or changes in material properties, such as electrical properties. The application of oil or grease etc. also reduces or protects the surface from such damage. Due to the release properties, welding effects of the heater to the heat shrink sleeve can be avoided.

[0043] The electric heating unit on the surface of the outer sleeve can include multiple heating elements, which first heat the outer sleeve, which contacts the next inner sleeve after shrinking. Then the two sleeves shrink together until they contact the other sleeve on the inside. Finally, the entire assembly shrinks until it conforms to the substrate below. The substrate below can be an MV cable joint area, with at least two cable ends and at least one connector for the main conductor. In most cases, other devices for connecting the shielding of the cable are located on the outside of the (unshrinked) joint body. Preferably, these are positioned before the installation process, which allows the installation process to be a single step process of installing the outer sleeve and the inner sleeve together.

[0044] In particular, two or more heating elements may be arranged outside the outer sleeve, the heating elements being energized at different times during the heat shrink installation process. In other words, the heating element located in the center (above the electrical connector) is energized to a high level in the first period. Subsequently, the other two heating elements located on both sides of the first heating element are energized to a high level. The term "subsequently" is defined either by a certain time, i.e., a number of minutes, or by a certain state during the heat shrink installation process, such as when the outer sleeve begins to shrink, or it has shrunk onto the next inner sleeve, or all sleeves including the innermost sleeve shrink together, or all sleeves have finished shrinking and contact the underlying substrate.

[0045] In addition to being controlled to heat or not heat only, the heating unit can also be controlled to perform steps such as pre-heating and post-heating, using lower levels of power in addition to being energized to a high level sufficient to perform the heat shrinking process of the sleeve(s). This speeds up the installation process and reduces thermal stress on the components and substrate. In particular, the electric heating unit is controlled to heat different zones of the sleeves along the longitudinal axis of the inner and outer heat shrink sleeves at different times during thermal recovery.

[0046] For reliable electrical performance, in many cases, a gradual contraction process starting from the center portion of the inner sleeve (eg, the connector body), then continuing toward the end of the connector body, and finally reaching the end of the re-sleeved sleeve is advantageous.

[0047] The logic of arranging multiple heating elements along the length of the outer sleeve and energizing them sequentially continues all the way to the end of the re-encapsulated sleeve. This allows the air to be evacuated and / or avoids the entrapment of air, especially in the sealing area of ​​the cable sheath or in the electrical interface. A similar effect can be obtained when the heater systems overlap, which generates more heat energy in the overlapping area. So the shrinking process starts here.

[0048] In the case of installing MV joints using heat shrink fitting bodies and heat shrink sleeves as re-sleeve sleeves, the average power density of the heater system can be 0.1W / cm 2 and 4.0W / cm 2 Between, preferably between 0.2W / cm 2 and 0.8W / cm 2 between.

[0049] In order to heat the heater system with voltages up to 24 volts to a temperature that allows a prompt and reasonably fast installation process of about 10-30 minutes for a standard 24 kV in-line joint, a copper conductor can be used as the heating wire. The heating wire can be arranged on a flexible carrier material so that the heating unit can be wrapped around a heat shrink cover and can be easily removed after the installation process is completed.

[0050] The carrier material of the heating wire can be a polyimide (PI) or polyethylene naphthalate (PEN) film with an adhesive material. The thickness of the film can be in the order of 10 microns, but less than 80 microns. This supports wrinkling and folding by low force when the heat shrink part shrinks. The heating element can include two layers of polymer film, one or both of which are covered with an adhesive. The heating wire can be laid in a curved manner with a conductor spacing of at least 2.5 mm to avoid film delamination before or during the installation process.

[0051] Furthermore, in the case of installing an MV joint using a heat shrink fitting body and a heat shrink sleeve as a re-fitting sleeve, the size of the heater system can be selected to have at least one heater system in the central area above the connector, the width of which is, for example, no longer than 100 mm, preferably as long as the connector or 50% shorter. The left and right heaters in the fitting body area on each side of the end of the fitting body should not be longer than 50 mm, but are preferably 20 mm longer on each side and not shorter than 5 mm on each side. The heaters at the ends of the re-fitting sleeve on each side should not be longer than 60 mm, but are preferably covering the ends of the re-fitting sleeve, or are preferably 15 mm longer on each side.

[0052] The concept of having a heater system that is shorter than the length of the connector supports reliable initiation of the shrinking process in the central area of ​​the connector. The much shorter length of the central heater(s) is also important because of the positioning tolerances of the re-sleeving sleeve relative to the fitting body.

[0053] If the heaters on each side of the fitting body are relatively longer than 20 mm, this may cause a portion of the resleeve to retract beyond the end of the fitting body, resulting in air entrapment. If the heaters are approximately the same length as the fitting body or shorter, this may result in incomplete retraction of the fitting body. If the next heater is energized, the resleeve may retract relatively quickly, which may result in air being trapped under the sleeve, which will not result in electrical failure of the fitting, but may result in failure of the butt joint between the cable jacket and the resleeve, which seals against the ingress of water or other material.

[0054] The heater is of the same length as the sleeve, which ensures that the sleeve is fully retracted to the end. Since heat is lost to the environment, a simple method has been found to compensate for the heat loss.

[0055] Although reference has been made above to arranging the heating systems side by side with little or no overlap, similar effects may be achieved and similar design parameters are valid where extensively overlapping heating systems are used.

[0056] In the case of installing an MV connector, the connection of the cable shield can be completed after the connector body is positioned and before the sleeve is positioned, and of course before the heat shrink installation.

[0057] The connection of the cable shields can be done by arranging the shield wires of the two cables into a common connector or, in the case of shielded cables, a corresponding system with a so-called cheese grater can be used. Separate elements such as rods, multiple wires, braids and / or multiple metal strips connected to each cable shield are also possible. Advantageously, the element has a certain elasticity to allow a certain degree of conformity to the outer shape of the installed connector body.

[0058] In this case, it is preferred that the pre-installed cable shield connection is located primarily at the top of the connector body. Due to gravity, the connector body is in contact with the connector and cable in the upper area. This area is minimally deformed and repositioned during the heat shrinking process. This is important because the shield connection system may have a certain mechanical stiffness, which may negatively affect the shrinking process and / or cause damage or punctures to the re-fitting or combination.

[0059] To facilitate removal of the heat transfer film and / or heater system after installation, it has been found to be advantageous to cover the interface on the outer heat shrink sleeve with a substance that prevents adhesion. In addition to using a powder such as Teflon, it is also useful to apply a small amount of silicone oil or the like. This release agent material should be able to withstand heating temperatures up to 200°C and above. The release agent material can be filled with substances that improve heat transfer, such as metal powders.

[0060] The method may further comprise the step of attaching an insulating sleeve for at least partially covering the heating unit. Such insulation at least partially prevents heat from escaping to the environment. Thus, firstly the heating efficiency is improved. Furthermore, heat transfer to adjacent objects is avoided, which may be important from a safety point of view. Therefore, the mounting kit may further comprise an insulating sleeve for at least partially covering the heating unit. For example, the insulating sleeve may comprise at least one bag filled with insulating particles.

[0061] The invention also relates to a mounting system, comprising a mounting kit and a control unit for controlling the electric heating unit to provide heat during a thermal recovery step to thermally recover the inner heat shrinkable sleeve. Advantageously, the control unit outputs a power supply voltage, and the heating unit is provided with a plug connector for connecting to the control unit during the thermal recovery step. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The accompanying drawings are incorporated into the specification and form a part of the specification to illustrate several embodiments of the present invention. These drawings, together with the description, are used to explain the principles of the present invention. The drawings are only for the purpose of illustrating preferred and alternative examples of how to make and use the present invention, and should not be interpreted as limiting the present invention to only the embodiments shown and described. In addition, several aspects of the embodiments may form solutions according to the present invention alone or in different combinations. Therefore, the embodiments described below may be considered alone or in any combination thereof. As shown in the accompanying drawings, further features and advantages will become apparent from the more specific description of various embodiments of the present invention below, in which the same reference numerals refer to the same elements, and in the accompanying drawings:

[0063] Figure 1 is a perspective view of a cable connector area as an example of a component to be covered;

[0064] Figure 2 is a schematic diagram of an example of an electric heating unit;

[0065] Figure 3 yes Figure 2 Details of the electric heating unit shown;

[0066] Figure 4 is a schematic timing diagram for energizing an exemplary electric heating unit having 12 heating sections;

[0067] Figure 5 shows a schematic diagram of a cable joint with inner and outer heat shrink sleeves and an electric heating unit before heating occurs;

[0068] Figure 6 yes Figure 5 Schematic diagram of the arrangement during heating;

[0069] Figure 7 yes Figure 5 A further schematic diagram of the arrangement during heating;

[0070] Figure 8 is a perspective view of a mounting system for mounting a heat shrink cover. DETAILED DESCRIPTION

[0071] Reference will now be made to the drawings and first to Figure 1 The invention is explained in more detail.The present disclosure relates to a mounting concept for mounting an electrical insulating cover on an object to be covered, such as a Medium Voltage (MV) joint. Figure 1 The connection between the first cable 102 and the second cable 104 is shown, the area forming the component to be covered 100. The first and second cable cores 106, 108 are electrically connected by a conductive connector 110 as known to those skilled in the art.

[0072] like Figure 1 As shown, when installing a heat shrink cover on the component 100 to be covered, essentially four different areas along the longitudinal axis of the two cables must be considered.

[0073] Area 1 is the central area, i.e. the area of ​​the cable connector 110. The cable connector 110 is a metal part that is in direct thermal contact with the cable conductors 106, 108. This means that this central area can be a significant heat sink (at low temperatures). The cable conductor cross section is 25mm 2 and 1000mm 2 The conductor material is usually aluminum, but copper is also common. The size of the cable connector 110 varies depending on the cable conductor size. The temperature inside the heat shrink product is usually 60°C to 120°C, depending on the wall thickness and structure of the sleeve.

[0074] If it is a sleeve with only heat shrink material, the temperature inside may be 90°C to 120°C during installation. If it has an elastomer layer inside, the temperature can be about 60°C. Once the inside of the heat shrink component contacts the connector 110, the connector 110 absorbs a lot of heat. As mentioned above, the temperature of the cable conductors 106, 108 can drop to -10°C, even if the cable ends 102, 104 are partially heated during the cable preparation work. The reason for this effect is that at least one cable is underground for a long time.

[0075] Cold connectors that absorb a lot of heat may require longer post-heating times compared to other areas of the joint. The length and intensity of post-heating varies with temperature, cable cross-section and conductor material, and connector size and material.

[0076] Region 2 (present on both sides of connector 110 but labeled on only one side in the figure) represents the insulating region, i.e. the region between the end of the connector body forming the heat shrink sleeve (not shown in this figure) and the center region (region 1).

[0077] The characteristic of this area is that cable conductor 106,108 is encapsulated by insulating material 112, and this insulating material is polyethylene (PE) normally.Three factors mainly affect the heat dissipation performance in this area: the thickness and material of cable conductor cross section, conductor material and insulating material 112. The latter depends on voltage level (12kV to 42kV). The heating sequence can change according to the ambient temperature in these three factors and / or the installation process that affect heat dissipation performance.In zone 2, the connector body must conform to the cable insulating material 112 as much as possible, so that exhaust air and close the axial electrical interface.In addition, when the connector body has an elastomer inner layer, it is crucial to make this layer firmly adhere to the cable insulating material 112.

[0078] Taking into account the above-mentioned influencing factors of the cables 102, 104, these effects are mainly achieved by a suitably long post-heating period.

[0079] Area 3 refers to the screen cutting area. In the screen cutting area, mastic or other conformable materials can be applied in many applications.

[0080] Typically, at the screen cut area (Zone 3), a conforming material 116 ("putty") is applied to treat the geometric step from the cable insulation 112 to the conductive outer layer 115. For proper electrical performance of the joint, the conforming material 116 must be heated to a certain temperature throughout its entirety and needs to be exposed to a certain (minimum) radial pressure. The factors affecting the heating sequence are similar to those of Zone 2, with lower cable temperatures resulting in longer post-heating times.

[0081] The outermost region 4 is the sealing area outside the connector body where the re-sleeve generally must seal against the cable jacket 114 .

[0082] The cable sheath 114 is usually a few millimeters thick and is made of a polymer material. Under the cable sheath 114 are the shielding wires or metal tapes, which have a relatively low cross-section. The heating sequence in these areas is less dependent on the surrounding cable temperature than in the area of ​​the joint body. Another aspect is that the requirements in terms of installation quality are lower than those for the joint body, which produces the main insulation.

[0083] To achieve a proper watertight seal, the hot melt material often used on the inside of the heat shrink tubing needs to be heated and softened, as does the outside of the cable jacket. Therefore, the post-heating time depends largely on the temperature measured in this area.

[0084] Figure 2 A schematic plan view of an electric heating unit 300 is shown (before being formed into a cylindrical shape) comprising seven heating elements 306 . The heating elements 306 are formed from wires 302 .

[0085] The heating elements are arranged symmetrically with respect to the central axis, and when the heating unit 300 is wrapped around the heat shrink cover, the central axis will be annular. Figure 2 As shown, the central heating element and the two peripheral heating elements are constructed as separate heating elements, each having two separate connecting elements. In contrast, the heating elements adjacent to the central heating element are connected in series with each other, and the two heating elements adjacent to the peripheral heating element are interconnected in series. Therefore, the number of connecting elements at the connector 304 can be reduced, taking into account that the internal heating element always operates symmetrically. Another reason is to produce a narrow heating element that is only half the length of the copper wire. Connecting these two in series will produce a heater with a typical wire length and typical process parameters.

[0086] Figure 3 yes Figure 2 Detail of , showing the arrangement of wire 302 on substrate 308. In an exemplary embodiment, wire 302 is formed of a copper conductor having a diameter between 0.15 mm and 0.8 mm. Substrate 308 can be formed, for example, of a polyimide (PI) or polyethylene naphthalate (PEN) film with an adhesive material. The thickness of the film can be on the order of 10 microns, but less than 80 microns. When the heat shrink component shrinks, this supports wrinkling and folding by low force. The heating element can include two layers of polymer film, one or both of which are covered with an adhesive.

[0087] Figure 4 An example of a timing for energizing a heating unit having 12 heating elements (heaters 1 to 12) arranged adjacent to each other in the direction along the longitudinal axis of the heat shrinkable cover is shown. In this arrangement, heaters 1 and 2 are heating elements arranged in the center of the heating unit, heater 3 is on the left side of heater 1, and heater 4 is on the right side of heater 2. In addition, heater 5 is adjacent to heater 3, heater 6 is adjacent to heater 4, and so on, until heaters 11 and heaters 12 as peripheral heating elements.

[0088] According to the present disclosure, a control unit selects a specific heating sequence based on a set value indicating the type of component to be covered and / or the type of heat shrink cover used. Preferably, the set value also contains information about the temperature of the component to be covered. In general, the colder the cable and cable accessories, the longer the post-processing period that must be selected. The extension also depends on the heat dissipation characteristics of the substrate (area). The duration of the preheating and full heating periods is affected by the initial temperature of the cable accessories and their size (i.e., voltage level), rather than the cable temperature. Depending on the voltage level, the wall thickness of the connector body is also different. This means that the heating sequence of connector bodies with higher voltage levels is usually longer.

[0089] Another option is to reduce installation time by preheating the product prior to positioning on the cable and / or before actual installation begins.

[0090] Figure 4 The sequence given in shows exemplary voltage values ​​that, together with the resistance of the heating elements, generate enough heat to shrink the heat shrink cover in the area where they are located. In this example, it is 22 volts (DC). At about the time of switching from 22 volts to a lower value, the heat shrink cover shrinks in the area of ​​the heating element. Voltage values ​​below 10 volts do not generate enough heat to bring the heat shrink cover to shrinking temperature, but will raise its temperature above room temperature.

[0091] Figure 4The sequence shown in allows for the generation of heat waves that travel through the heat shrink product, starting from the center and progressing to the ends. Each heating element not only generates enough heat to shrink the heat shrink cover in the area in which it is located, but also generates heat to increase the temperature of the adjacent areas. When the heater elements in those adjacent areas are later switched to 22 volts, the uneven initial temperature in the area causes the heat shrink dynamics to start from the area close to the previous heater and then develop to the opposite end. The width of the heater elements, and thus the performance of the heat shrink cover, must be selected based on experimentation and / or trials. Heating elements with a lower width allow for easier generation of heat waves and gradual shrinking of the heat shrink cover.

[0092] Therefore, the control unit selects Figure 4 The 50 minute schedule is shown as the optimum schedule for parts with room temperature.

[0093] It can be seen from the figure that in the first 6 minutes, the maximum voltage of heaters 1 and 2 is 22V and the current is 8A, that is, the total power of the two heating elements is 352W. This is the main heating stage, and no preheating stage is performed in this area.

[0094] Heaters 3 and 4, directly adjacent to heaters 1 and 2, are energized at a lower voltage and current (8V, 3A, i.e. 48W for two heating elements), thus undergoing a preheating phase. Further out, heaters 5 and 6 are energized at 5V and 2A, resulting in a total energy of 20W. The remaining heaters 7 to 12 are not energized at all during this period. As a result, the heat shrink cover remains cool and does not shrink in these areas, so that the air can be squeezed outwards.

[0095] Returning to heaters 1 and 2, the energy supplied to these two heating elements is reduced after 6 minutes and remains at 18V, 6.5A (i.e. 234W in total) until the end of 15 minutes after start-up. This is called the post-heating phase. The energy is then reduced again for 4 minutes and completely turned off after 20 minutes. After this, the heat shrink covers under these two heating elements have completely shrunk and have heated the underlying cable section to some extent in order to improve the fit and conformity of the heat shrink covers, resulting in a tighter electrical interface.

[0096] On the other hand, heaters 3 and 4 heat with maximum power (voltage of 22 V and current of 8 A, i.e. 352 W for both heating elements in total) in their main heating phase, starting from 7 minutes after start-up until 18 minutes after start-up. The energy is then reduced (post-heating phase) and switched off after 27 minutes after start-up. Heaters 7 and 8 start with their pre-heating phase, with a lower amount of energy introduced after 20 minutes after start-up, and with the highest amount of energy during the main heating phase, which takes place between 33 and 37 minutes after start-up.

[0097] Heaters 5 and 6 start with a preheating phase from the beginning and have their main heating phase (22V, 8A) in a period between 20 minutes and 32 minutes after starting. The post-heating phase at 15V lasts from 33 minutes to 37 minutes. Then, heaters 5 and 6 are turned off. Compared with the other heating elements, heaters 5 and 6 (together with heaters 3 and 4) have the longest main heating phase.

[0098] Heaters 7 and 8 start the preheating phase 20 minutes after the start of the heating sequence, in other words, at the same time as the start of the main heating phase of the adjacent heaters 5 and 6. From the end of the main heating phase of heaters 5 and 6, the power is slowly increased, and the main heating phase lasts 5 minutes. Heaters 7 and 8 do not perform a postheating phase.

[0099] For heaters 9 and 10, the 11-minute preheating phase started 27 minutes after the start of the sequence. The main heating phase started 39 minutes later and lasted 5 minutes. This was followed by 3 minutes of post-heating.

[0100] Peripheral heaters 11 and 12 have a fairly short 5 minute preheat, starting 39 minutes after start-up, and have their main heating phase at the end of the total sequence, with a slight reduction in energy at the end, and no significant post-heat phase. The sequence ends at 50 minutes when peripheral heaters 11 and 12 are turned off.

[0101] like Figure 4 As shown in (right column), one joint can be covered at a time. Alternatively, three joints can be covered simultaneously. Of course, when shrinking three heat shrink covers simultaneously, the total power that must be provided is higher.

[0102] Figures 5 to 7 It is shown how, for a simpler heating unit having only five heating elements, a heat wave is generated from the center of the heat shrink cover to the periphery.

[0103] The cover 1000 comprises an outer sleeve 1102 and an inner sleeve 1104. The example explained below relates to the installation of at least two sleeves, wherein the inner sleeve is a heat shrink sleeve, by heating the outermost sleeve from its outside. A special application is the heat shrink installation of an MV joint of an electric heating system. For example, the outer sleeve 1102 is a re-sleeving sleeve, while the inner sleeve 1104 is a joint body, both sleeves being separate components and manufactured with at least one heat shrink layer. The two sleeves are positioned independently of each other in the cable joint area. According to the invention, the two sleeves are installed in an installation sequence, in other words, in a heating sequence, without interaction of the joint parts. At the end of the installation process, the electric heater and all other items required for the installation process can be removed.

[0104] like Figure 5As shown, the cover 1000 also includes an electric heating unit 1110, which is arranged on the outer surface 1108 of the outer sleeve 11102. The heating unit 1110 provides all the heat energy required to shrink the outer and inner sleeves 1102, 1104. Figure 5 In the example shown, both sleeves 1102, 1104 include at least one heat shrink layer that allows the sleeves to recover to a smaller diameter when the sleeves are heated to a recovery temperature.

[0105] Advantageously, the outer sleeve 1102 is longer than the inner sleeve 1104 in the longitudinal direction along the middle axis 1112. Thus, a reliable sealing of the connection covered by the first and second sleeves 1102, 1104 can be achieved. However, the first and second sleeves 1102, 1104 can of course also have the same length.

[0106] Figures 5 to 7 The installation process according to the present invention is schematically shown. In a first step, the inner sleeve 1104 and the outer sleeve 1102 are arranged to surround the part to be covered 1114. The heating unit 1110 is arranged on the outer surface of the outer sleeve 1102. The electric heating unit 1110 can have a plurality of heating elements 1116. These heating elements 1116 can be powered individually so that the following areas can be heated differently along the longitudinal axis 1112, or connected in series to form a heating element pair that is energized together.

[0107] The heating unit first heats the outer sleeve 1102 in a central area determined by the size of the heating element 1116c, which contacts the outer surface of the inner sleeve 1104 after thermal recovery and contraction. Figure 6 middle.

[0108] Then, the two sleeves 1102, 1104 are shrunk together until the other sleeves inside touch (not shown). Finally, the entire assembly is shrunk until it conforms to the underlying substrate 1114. The final situation is as follows: Figure 7 As already mentioned, the underlying substrate 1114 may be a MV cable splicing area, with at least two cable ends and at least one connector for a main conductor.

[0109] Figures 5 to 7 An exemplary arrangement is shown in which the MV cable joint area is covered by a joint body forming an inner sleeve 1104 and a re-sleeved sleeve forming an outer sleeve 1102. Both sleeves 1102, 1104 are heat recoverable, i.e., they include at least one heat shrink layer. According to this embodiment, a first cable end 1118 is connected to a second cable end 1120. As known to those skilled in the art, a first main conductor 1122 and a second main conductor 1124 are connected to each other by an electrical connector 1126.

[0110] An electrical shield connector 1128 is provided for electrically connecting the first electrical shield wire 1130 of the first cable 1118 and the second electrical shield wire 1132 of the second cable 1120. The shield connector is attached before the re-sleeve 1102 carrying the heating unit 1110 is arranged around the cable connection area. It should be noted that the arrangement is slightly asymmetrical due to the shield connection.

[0111] According to this example, the heating unit 1110 includes five adjacent heating elements 1116a to 1116e. During the heat shrink installation process, the heating elements 1116a to 1116e are energized at different times. Preferably, the heating element 1116c located in the center above the connector 1126 is energized to a high level in the first stage, such as Figure 6 As shown. Therefore, the central area of ​​the outer sleeve 1102 begins to shrink toward the inner sleeve 1104. In the next stage, as shown Figure 7 As shown, only heating elements 1116b and 1116d are energized or are energized in addition to heating element 1116c. Finally, the outermost heating elements 1116a and 1116e are energized to completely seal the connection of the re-sleeved sleeve 1102. (This state is not shown in the figure.) At this time, heating element 1116c and heating elements 1116b and 1116d may not be energized or energized at a lower level to produce post-heating, or simply because less energy is required to continue the heat shrink installation once the shrink process has begun.

[0112] The order in which the heating elements 1116a to 1116e are controlled can be defined by certain absolute time intervals or certain states during the heat shrink installation process. For example, it can be determined when the outer sleeve 1102 begins to shrink, or when it contacts the next inner sleeve, or when all sleeves including the innermost sleeve shrink together, or when all sleeves have completed shrinking and have contacted the underlying substrate. In addition, the heating elements 1116a to 1116e can also be arranged to overlap or be far away from each other, rather than as Figures 5 to 7 are shown arranged adjacent to each other.

[0113] Furthermore, in addition to merely energizing the heating elements 1116a to 1116e, i.e., turning them on or off, the heating elements 1116a to 1116e may also be controlled to heat at different power levels, as described with reference to FIG. Figure 4As explained. For example, in order to perform the preheating and postheating steps, in addition to stimulating the heating elements 1116a to 1116e to a high level sufficient to perform the sleeve heat shrinking process, the heating elements 1116a to 1116e can also be driven with a lower level of power. Therefore, the installation process can be accelerated and the thermal stress on the components and the substrate below can be reduced. In order to obtain reliable performance, in many cases, a gradual shrinking process is required, starting from the center portion of the joint body, then continuing toward the end of the joint body, and finally reaching the end of the sleeve that is re-fitted.

[0114] Furthermore, the concept of positioning multiple heating elements 1116a to 1116e along the length of the outer sleeve 1102 and energizing them sequentially continues until the end of the re-sleeving. This allows for the evacuation of air and / or avoidance of trapped air, especially in the sealing area of ​​the cable sheath or electrical interface. A similar effect can be obtained by using overlapping heating elements that generate more energy in the overlapping area. Thus, the shrinking process starts from the overlapping area.

[0115] According to the invention, set values ​​of set parameters indicative of the mounting arrangement are retrieved and used to select a specific heating sequence over time and in the axial direction.

[0116] In particular, the selection of the heating sequence depends on the temperature of the cable, the specific materials and geometries of the cable and cable connectors, the specific materials and geometries of the inner and outer jackets, and / or the ambient temperature.

[0117] One possibility to retrieve information about these parameters is to use a control unit that can read the identification of the cover to be installed. The identification of a specific type of cover is associated with the size and material of the cover. Furthermore, a specific type of cover is usually only used for a specific type of cable and connector. Therefore, the material and size of the cable and connector are also indirectly indicated by the identification of the cover. The specific heating sequence required to shrink this specific cover can, for example, be stored in a table in the control unit or can be retrieved from an external database, for example from a label on the product.

[0118] Furthermore, the temperature sensor can provide information about the temperature at the cable (and optionally also the temperature of the surrounding air), so that the applied heating sequence can be selected by additionally taking the measured temperatures into account.

[0119] The following will refer to Figure 8 A mounting system 200 for mounting a heat shrink cover on a component to be covered according to the method of the present invention is described. Figure 8As shown, the installation kit 202 includes an inner sleeve 204 and an outer sleeve unit 206. The outer sleeve unit 206 includes a heat shrink sleeve (not visible in this figure) according to one of the above-mentioned embodiments, which covers an electric heating unit (not visible in this figure) and an optional insulation unit (not visible in this figure). The heating unit includes at least one connector lead 208 with at least one plug connector 210.

[0120] To provide electrical energy to the heating unit, the mounting system 200 comprises a control unit 212. The heating unit is connected to a mating connector 214 via a plug connector 210. The control unit 212 can be connected to a mains power supply or a battery or the like via a power plug 216. A control panel 218 with keys and a display allows manual interaction by an operator. The control unit 212 can also advantageously be used to control the intensity of the heating and, in the case where the heating unit is equipped with individually addressable heating zones, to control the sequence of activated heating zones. It can also detect the actual (average) temperature of the heating unit to a certain extent by tracking the voltage and / or current. The control unit can also modify or select another set of process parameters, such as voltage, current and time period, based on ambient temperature and / or measured or manually entered data of the heat shrink cover. The control unit can also track actual product and process parameters as well as GPS data of the joining location, or, for example, the identity of the installer or cable.

[0121] In order to identify a specific outer cannula unit 206, the control unit 212 advantageously also includes an identification reader, such as a barcode or QR code reader 220. The outer cannula unit 206 is equipped with a QR code tag 222 (or any other suitable identification means) for identifying the type and structure of the outer cannula unit 206 by the reader 220.

[0122] Advantageously, the operator first reads the identification tag 222 of the installation kit 202. Next, the inner sleeve 204 is arranged at the desired position on the component to be covered. The shield connection is then completed. Now, the outer sleeve unit 206 is arranged to cover the inner sleeve 204, and the connector 210 is connected to the mating connector 214. The mating connector provides thermal energy via the low-voltage cable 230. The control unit is connected to the power supply via the power cable 230 and the power plug 216. The operator can now enter the command required to start the heating program belonging to the registered identification of the identification tag 222, or a heating program using the data that may be contained in the identification tag 222, which heating program may require the use of a QR code instead of a barcode.

[0123] After the heating process is completed, the part to be covered is surrounded by the heat shrink inner sleeve 204 and the heat shrink outer sleeve (not shown in this figure). According to the invention, the heating unit, the optional extrusion device and the optional insulation unit are removed and discarded. Advantageously, no torch is required, the details of the heating sequence are controlled by a program stored in the control unit 212, or the data are contained in the identification tag 222.

[0124] Furthermore, the identification reader 220 can also be connected to the control unit 218 in a pluggable manner so that it can be easily replaced. Furthermore, the installation process can of course also be controlled by communicating directly with the control unit 216 without using an identification device. It goes without saying that wireless communication can also be provided for remote communication with the control unit 216. Furthermore, one or more communication ports can be provided, such as a universal serial bus port 234. An emergency switch 232 can be provided for overriding the control program and switching off the heating when required.

[0125] The present invention can be used illustratively for an arrangement in which the electric heater is located outside an outer sleeve (e.g., a re-fitting sleeve). The connector body forming the inner sleeve and the re-fitting sleeve can be installed without further interaction of the cable connector. During the first phase of the thermal recovery process, the re-fitting sleeve is heated and shrinks at least over part of its length. When the re-fitting sleeve contacts the connector body below, heat is transferred into the connector body. After a period of time, the connector body is heated to the shrinking temperature. The two sleeves then shrink together until the inner sleeve (i.e., the connector body) contacts the part to be covered. Because the heater is located outside the re-fitting sleeve, it can be easily removed after the installation process is completed.

[0126] Of course, the invention can also be used in any other application environment besides installing only MV joints to shrink at least two sleeves by electrically heating the outermost sleeve from the outside. Many aspects of the invention can also be used to install a single heat shrink sleeve.

[0127] Finally, it must be noted that any values ​​or specific properties of the electrical and electronic components described are intended only as examples and can of course be changed as needed in order to adapt the circuit to the specific needs of a specific application environment. In addition, although the embodiments have been described in conjunction with specific examples, the present invention is not limited thereto, and a variety of changes may be made to the disclosed embodiments without departing from the scope of the present invention. Therefore, the various embodiments and examples are not intended to be limited to the specific forms disclosed. On the contrary, they include modifications and substitutions that fall within the scope of the claims, and the individual features can be freely combined with each other to obtain further embodiments or examples according to the present invention.

[0128] Reference numerals list

[0129] 100 Attachments to be covered

[0130] 102 First Cable

[0131] 104 Second Cable

[0132] 106 First Cable Core

[0133] 108 Second cable core

[0134] 110 Cable Connector

[0135] 112 Edge material

[0136] 114 Cable sheath

[0137] 115 Conductive outer layer

[0138] 116 Laminating material; glue

[0139] 300 Heating Unit

[0140] 302 Heating wire

[0141] 304 Heating Wire Connector

[0142] 306 Heating element

[0143] 308 Electrically insulating substrate

[0144] 1000 Cover

[0145] 1102 Outer sleeve; re-sleeved sleeve

[0146] 1104 Inner sleeve; connector body

[0147] 1108 Outer surface of outer sleeve

[0148] 1110 Heating unit

[0149] 1112 longitudinal middle axis

[0150] 1114 Attachments to be covered

[0151] 1116; 1116A-1116e Heating element

[0152] 1118 First cable end

[0153] 1119 First Cable Sheath

[0154] 1120 Second cable end

[0155] 1121 Second cable sheath

[0156] 1122 First Main Conductor

[0157] 1124 Second Main Conductor

[0158] 1126 Electrical connector

[0159] 1128 Shielded Connector

[0160] 1130 First shield line

[0161] 1132 Second shielding line

[0162] 200 Insulation System

[0163] 202 Installation Kit

[0164] 204 Inner casing

[0165] 206 Outer casing unit

[0166] 208 Connector Leads

[0167] 210 Plug connector

[0168] 212 Control Unit

[0169] 214 Mating connector

[0170] 216 Power plug

[0171] 218 Control Panel

[0172] 220 code reader

[0173] 222 Identification (QR code) label

[0174] 226 Power Cable

[0175] 228 Power connection

[0176] 230 Low voltage cable

[0177] 232 Emergency switch

[0178] 234 Communication port

Claims

1. A method for installing a heat shrink cover around a component to be covered, performed by an electric heating system, the electric heating system comprising an electric heating unit and an electronic control unit connected to the electric heating unit, the method comprising the following steps: attaching the electric heating unit to the outer surface of the heat shrink cover; Arranging the heat shrinkable cover around the component to be covered; Retrieving at least one setting parameter of the heat shrink cover and the component to be covered, and generating at least one setting value indicating the at least one setting parameter; wherein retrieving at least one setting parameter comprises acquiring first configuration data characterizing at least one area of ​​the component to be covered; wherein retrieving at least one setting parameter comprises measuring the temperature of the component to be covered; wherein the component to be covered is a cable connection, and wherein the first configuration data comprises information indicating a cable type and a cable diameter and / or a connector type and / or a sealing material; an activating step of activating the electric heating unit to provide heat for thermally restoring the heat shrinkable cover, wherein the activating step is performed in response to the at least one set value.

2. The method according to claim 1, wherein: Retrieving at least one setting parameter includes acquiring second configuration data characterizing the heat shrink cover.

3. The method according to claim 2, wherein: The second configuration data includes information indicating a material thickness and / or a material composition of the heat shrink cover.

4. The method according to any one of claims 1 to 3, wherein: The energizing step includes at least one of a heating phase, a main heating phase, and a post-heating phase, wherein the heating phase is used to at least partially heat the heat shrink cover to a temperature below the installation temperature, the main heating phase is used to heat the heat shrink cover until the heat shrink cover is at least partially shrunk, and the post-heating phase is used to introduce further thermal energy after the heat shrink cover has been at least partially shrunk.

5. The method according to any one of claims 1 to 3, wherein: The electric heating unit comprises a plurality of heating sections operable to be energized in response to control signals provided by the electronic control unit.

6. An electric heating system for installing a heat shrink cover around a component to be covered, wherein the electric heating system comprises an electric heating unit and an electronic control unit connected to the electric heating unit, and wherein the electric heating system is operable to perform the method according to any one of claims 1 to 5.

7. The electric heating system according to claim 6, further comprising a temperature sensor for measuring the temperature of the part to be covered.

8. The electric heating system according to claim 6 or 7, further comprising an input device for inputting the at least one setting parameter of the heat shrinkable cover and / or the component to be covered.

9. The electric heating system according to claim 8, wherein: The input device includes an input device for inputting the ID code of the heat shrink cover, and includes a barcode reader, an RFID reader, a QR code reader, a wireless communication interface and / or a manual input interface and / or a wired connection to a chip located at the heat shrink cover.

10. A mounting system comprising: An installation kit, the installation kit having a heat shrink cover and the electric heating system according to claim 6, wherein the heat shrink cover is covered with an electric heating unit of the electric heating system.

11. The mounting system according to claim 10, further comprising a temperature sensor for measuring the temperature of the component to be covered and / or the temperature of the air in the environment of the component to be covered and / or the temperature of the heat shrink cover.

12. The mounting system according to claim 10 or 11, further comprising an input device for inputting an ID code of the heat shrink cover, wherein the ID code comprises a product identification and / or a product application range and / or a product attribute value.

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