Retrofit device and method for retrofitting, controlling and monitoring and for the energy management of existing switch-heating systems
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- BACKER ELC AG
- Filing Date
- 2024-07-04
- Publication Date
- 2026-05-20
AI Technical Summary
Conventional switch heating devices for rail-based transport systems consume excessive energy due to uniform heating strategies, leading to unnecessary power usage and potential malfunctions, as they lack individual control and are not suitable for retrofitting existing systems.
A retrofitting device and method that equip each switch heating element with a local control unit and temperature sensor, connected via a bus line or radio to a central control device, allowing for selective heating based on individual thermal conditions, enabling precise temperature management and load distribution.
This solution reduces energy consumption, enhances functional reliability by prioritizing heating in exposed areas, and allows for intelligent load management, minimizing disruptions and overheating, while enabling the retrofitting of existing systems for efficient energy use.
Smart Images
Figure CH2024050034_16012025_PF_FP_ABST
Abstract
Description
[0001] Retrofitting device and method for retrofitting, controlling, monitoring and energy management of existing switch heating systems
[0002] Technical area
[0003] The invention relates to a retrofitting device and a method for retrofitting, controlling, monitoring and energy management of existing switch heating systems.
[0004] State of the art
[0005] Switch heating devices for preventing the moving parts of switches in rail-based transport systems from freezing by heating the switches are well known. For example, electric heating elements with a connection head are used on the switch rails. The electric switch heaters are usually switched on and off as needed, either manually or by a central control system. The central control system switches several switches, each with several heating elements, on or off.
[0006] Such switch heating devices are known, for example, from WO 2019 / 075248A1, WO 2020 / 053842A2, or DE102014113541A1. A disadvantage of these conventional switch heating devices with manual activation or central control is that the central control switches all connected heating elements on and off together, or in groups, without knowing the exact thermal situation of each individual heating element. The thermal situation at the most exposed switch is usually the decisive factor for activation, which leads to unnecessary power consumption because individual heating elements in less exposed locations heat the rail to a higher temperature than required.Such heating systems are also prone to failure if, for example, the connected load is too low, and the power is unnecessarily consumed at less exposed points, while insufficient power is available at the important exposed points of the switch to reach the required rail temperature. Furthermore, the known control and switching elements are designed in such a way that, due to their size and nature, they cannot be mounted directly on a rail.
[0007] DE19832535A1 describes a device for controlling and monitoring point heaters. This device can record the outside temperature and weather-related precipitation, regulate the point heater temperature, and monitor the functionality of the components using control devices assigned to the point heaters. This is achieved by assigning decentralized control and monitoring units to the point heaters, and connecting the decentralized control and monitoring units to each other via a bus line and / or radio connection. Such devices can control and regulate groups of point heaters, but it is not common practice to control and regulate each individual heating element individually.Such a device is also not suitable for retrofitting an existing switch heating system and for learning independently how an existing switch heating system works and what temperature setpoints the existing system has.
[0008] Object of the invention
[0009] The present invention is based on the object of creating a method and a retrofit device for the control, monitoring, and energy management of point heating systems for the selective assignment of a control strategy to individual point heating devices, thereby enabling the retrofitting, control, monitoring, and energy management of existing point heating systems for the selective heating of points in a rail-bound transport system, and whereby the functionality of existing point heating systems can be recognized. The method and the retrofit device, and thus the retrofitting of existing systems, are intended to save energy for heating the rails, increase functional reliability through appropriate prioritized heating of exposed areas, and enable effective load management. Description of the invention
[0010] This task is solved by a method for retrofitting, controlling, monitoring and energy management of existing switch heating systems for the selective heating of switches for a rail-bound transport system, whereby the method comprises the following steps:
[0011] (A) several switch heating devices are attached to each switch, each switch heating device comprising a heating element, a connection head arranged on the heating element with a local control unit comprising a microprocessor and a power switch, and a temperature sensor arranged outside the connection head and connected to the local control unit, and each local control unit is connected by means of a bus line and / or radio connection to a central control device comprising a microprocessor, the central control device being installed in addition to an existing control system, the existing control system being connected to a temperature sensor on a predetermined rail,
[0012] (B) a temperature sensor of a switch heating device is defined as the main temperature sensor and is mounted immediately next to the temperature sensor of the existing control system so that both temperature sensors measure the same temperature;
[0013] (C) the microprocessor of the central control device detects a lower and upper temperature setpoint of the predetermined rail specified by the existing control system by means of this previously defined main temperature sensor and detects the information when the existing control system gives the command to switch on and off the point heaters on the predetermined rail, or when the point heaters on the predetermined rail switch on or off;
[0014] (D) the lower and upper temperature setpoints detected in step (C) or a predetermined lower and upper temperature setpoint are sent by the microprocessor of the central control device to the individual local control units of each switch heating device, or the microprocessor of the central control device sends a command to the individual local control units to switch the individual heating elements on or off;
[0015] (E) the local control unit of the point heating device compares the detected or specified temperature setpoint with a value measured by the temperature sensor on the respective point heating device and switches the heating element on if the lower temperature setpoint is undershot and switches the heating element off if the upper temperature setpoint is exceeded, or follows a command to switch the individual heating elements on or off without taking into account the previously specified temperature setpoint.
[0016] In a further embodiment, the central control device is connected to the existing control system, and the method comprises a further step between steps (B) and (C), in which the signals at the output of the existing control system are tapped and routed to the central control device. This means that the signals tapped at the output of the existing control system, such as the signals that specify the switching on and off of the heating element on the predetermined rail, are detected and processed by the central control device. This allows the upper and lower temperature setpoints of the predetermined rail to be determined more accurately and without delay.
[0017] A predetermined rail is the rail where, based on local conditions, the lower temperature limit is most likely to occur first, and where the main rail temperature sensor of the existing control system is mounted. The predetermined rail is also referred to as the guide rail and is usually located in a particularly exposed location.
[0018] A particular advantage of the method according to the invention is that it can be retrofitted to existing point heating systems. Conventional point heating systems typically have a single rail temperature sensor on a predetermined exposed rail, also known as the guide rail, which supplies the information to an existing central control system, whereby all heating elements connected to the control system are switched on and off jointly or in groups. This leads to increased energy consumption because the less exposed points are overheated. With the method according to the invention, a new central control device is installed in addition to or instead of the existing control system and connected to each local control unit of the newly installed point heating devices, preferably via a bus line or radio link.The central control unit detects the status of each individual switch heating device, of which there are several per switch or per rail. Each switch heating device comprises a heating element, a connection head located on the heating element with a local control unit with an integrated microprocessor, and a temperature sensor located outside the connection head and connected to the local control unit.
[0019] The central control unit detects the rail temperature at the point heater location via the temperature sensor and, based on this, provides the local control unit for each point heater with either a lower and upper target temperature or issues a command to switch on and off to distribute the load. This results in intelligent load management, in which power is distributed among different points to prevent excessive power consumption. This, in turn, reduces the susceptibility to failures because not all point heaters are switched on at the same time.
[0020] The local control unit can therefore receive instructions from the central control device and return status messages and temperature values. Each local control unit is also able to regulate itself within the specified temperature setpoints. If the central control device fails, the local control unit can detect this and independently perform the control function. The local control unit therefore functions both autonomously and, if required, on command and is self-learning. Like the central control device, the local control unit contains a microprocessor for processing the data. In addition to the microprocessor, the local control unit has a circuit breaker, also called a load switch, for switching the power on and off. In conventional systems, this function is usually performed by external circuit breakers in the control cabinet, so-called relays.This is a further advantage of the present invention that each individual switch heating device has a power switch directly on the rail and can therefore switch each heating element on and off individually.
[0021] In addition, a predefined internal temperature setpoint, which is used in the absence of communication with a central controller, can be individually parameterized for each local control unit.
[0022] A further advantage of the method according to the invention is that, with the retrofitted switch heating system, each individual switch heating device includes an integrated, independent control system that can react precisely and independently to the local thermal situation, both with and without a higher-level central control device. This leads to a significant reduction in energy consumption and a reduction in malfunctions. The invention enables the individual control of all heating elements. Each individual switch heating device knows its thermal situation and is able to react independently if the rail temperature exceeds or falls below a setpoint.
[0023] A temperature sensor of a switch heating device, defined as the main temperature sensor, is mounted on a predetermined rail directly next to the temperature sensor of the existing control system. The main temperature sensor of the retrofitted control system thus measures the same temperature as the temperature sensor of the existing control system. "Directly next to" means that the distance between the temperature sensor of the existing control system and the main temperature sensor is between zero and a maximum of 10 cm, i.e., directly adjacent to one another or with a maximum distance of 10 cm from each other. Preferably, each local control unit of each switch heating device is assigned a unique identification number (ID for short).In a preferred embodiment, each unique ID of the local control unit, and thus each switch heating device, is assigned a heating category with a temperature setpoint, so that each switch heating device can be assigned a different temperature setpoint. By assigning the heating categories to different categories, functional reliability can be improved and energy consumption can be reduced.
[0024] In a preferred embodiment, the individual point heating devices are assigned to different heating categories, preferably two or three different heating categories. The point heating devices at the tongue tip, or on the stock rail of a point located next to the tongue tip, or at another exposed point on a point, are preferably assigned to a first heating category and preferably have a higher lower and upper temperature setpoint than the point heating devices that are mounted further away from the tongue tip on the point and are thus less exposed. And the point heating devices that are not arranged at the tongue tip or at an exposed point on a point are preferably assigned to a second heating category and have a lower temperature setpoint than the point heating devices that are mounted at the tongue tip on the point.Depending on the assigned heating category, the switch heaters can be switched off, cyclically, and / or alternately switched on and off, for example, in the event of a power shortage or grid overload. If the existing connected load is insufficient to heat all switch heaters simultaneously, the less exposed switch heaters in the second or subsequent heating categories are heated at a reduced level. This means that the heating elements of the switch heaters in the first heating category always switch on when the temperature falls below the lower setpoint.However, if the power is insufficient to switch on all point heaters, the point heaters of the second and subsequent heating categories can be switched on and off in a cyclical and / or alternating manner, by switching on only some of the point heaters of the second heating category. Once they have reached a desired temperature, they are switched off again, and another part of the second heating category is switched on. Once the point heaters of the first heating category have reached the upper temperature setpoint, all point heaters of the second heating category can be switched on if they are still below the upper temperature setpoint.
[0025] A further advantage of the invention is that when both the tongue and stock rails are heated, the heating power on the closed tongue rail side, when it is in contact with the stock rail, is automatically reduced to prevent a temperature increase. However, when the tongue rail is open, the full heating power is applied on the open side of the tongue rail, which is vulnerable to snow and ice that can get between the tongue rail and stock rail.
[0026] This makes the present method ideally suited to keep energy consumption low, distribute the load in a targeted manner and thus minimize disruptions.
[0027] The switch heaters, each fitted with a connection head and integrated local control unit, are small and compact, allowing them to be mounted directly on a rail near a switch. The connection head is compact yet completely sealed. Each switch is preferably equipped with multiple switch heaters, which are preferably attached to both the stock rail and the tongue rail. In one embodiment, for example, each tongue and stock rail of a switch has two switch heaters each.
[0028] In another embodiment, the microprocessor of the central control device collects all data and sends it to an external server for storage and optimization. Furthermore, the software of the microprocessors of the central control device and the local control unit can be reprogrammed or a software update performed externally via a data connection. This is a further advantage of the present invention, as each local control unit and the central control device can be accessed externally.
[0029] In addition to the method, the present invention relates to a retrofit device for an existing point heating system, which comprises at least one central control device and a plurality of point heating devices, wherein a plurality of point heating devices are each attached to a point, wherein each point heating device comprises a heating element, a connection head arranged on the heating element with an integrated local control unit and a temperature sensor arranged outside the connection head and connected to the local control unit, wherein the at least one central control device is connected by means of a bus line and / or radio connection to each individual local control unit of the plurality of point heating devices, and wherein the central control device comprises a microprocessor for controlling, monitoring and for the energy management of point heating devices,so that a local rail temperature can be measured via the temperature sensor of a switch heating device connected to the local control unit, which can be detected by the microprocessor of the control device, wherein the microprocessor can send signals to each local control unit with an upper or lower temperature setpoint specification or with a command to switch the heating element on or off, and wherein the local control unit of the switch heating device is capable of regulating itself within the temperature setpoint specifications.
[0030] Such a retrofit device for an existing point heating system has the advantage that it can be installed as a replacement for or alongside a conventional control system for existing point heating systems. It can be used for the control, monitoring, and energy management of point heating systems, selectively assigning a control strategy to individual point heating devices. This allows an existing control system and point heating system to be optimized in terms of energy consumption and susceptibility to failure, thus enhancing its performance.
[0031] In one embodiment, the retrofit device comprises a plurality of central control devices, each of the plurality of central control devices being connected to a plurality of local control units of the plurality of switch heating devices, the plurality of central control devices being interconnected as a network via a bus connection, one of the central control devices assuming the master role and the other central control devices assuming the slave role, such that signals predetermined by the network can be sent to each local control unit with an upper or lower temperature setpoint specification or with a command to switch the heating element on or off, and each local control unit of the switch heating device being able to regulate itself within the temperature specifications and to switch itself on or off as required.In this way, point heating systems with hundreds of point heating elements can be operated, with each individual point heating device precisely following the temperature set by the network from the central control devices and being able to switch itself on and off as required.
[0032] In a further embodiment, the central control device is installed in addition to an existing control system, wherein the existing control system is connected to a temperature sensor on a predetermined rail, wherein a temperature sensor of a switch heating device is defined as the main temperature sensor and is mounted on a guide rail directly next to or at a distance of a maximum of 10 cm from the temperature sensor of the existing control system, so that both temperature sensors measure the same temperature.
[0033] In a further embodiment, multiple central control devices in the network work together with multiple existing controllers, or with one existing controller that has multiple main temperature sensors and operates switch groups. These multiple central control devices detect various setpoints from one or more existing controllers and control the switch heating devices accordingly. Preferably, one central control device is used per main temperature sensor group.
[0034] Preferably, each local control unit is assigned a unique identification number (ID) for each point heating device, and each unique ID, and thus each point heating device, is assigned a heating category with a predetermined lower and upper temperature setpoint, such that each point heating device can be assigned a different lower and upper temperature setpoint depending on the heating category. This allows the point heating devices to be switched off or switched on and off in a timed fashion, and / or alternately switched on and off, depending on the assigned heating category, for example, in the event of a power shortage or grid overload, thus distributing the load.
[0035] Furthermore, the present invention relates to the use of the retrofitting device according to the invention for retrofitting existing switch heating systems.
[0036] Combinations of two or more of the above-listed designs and variants are conceivable and claimed.
[0037] Further advantages of the invention will become apparent from the following description, in which the invention is explained in more detail with reference to embodiments shown in the drawings.
[0038] Short description of the characters
[0039] They show:
[0040] Fig. 1 shows a switch heating device in schematic representation,
[0041] Fig. 2 is a schematic representation of a retrofit device with three switch heating devices and a central control device with a connection between the central control device and an existing control system,
[0042] Fig. 3 is a schematic representation of a retrofit device with three switch heating devices and a central control device with a connection between a main switch heating device and an existing control system.
[0043] In the figures, the same reference symbols are used for the same elements and explanations of a specific reference symbol apply to all figures unless expressly stated otherwise.
[0044] Embodiments of the invention
[0045] Figure 1 shows a schematic representation of a switch heating device 3, 3' with a heating element 4, a connection head 2 arranged on the heating element 4 with a local control unit 5 with integrated microprocessor 13 and power switch 18, and a temperature sensor 6 arranged outside the connection head 2 and connected to the local control unit 5. The local control unit 5 of the switch heating device 3, 3' is connected to a central control device 7 (shown in Fig. 2 and 3) by means of a bus line 8 and / or radio connection.
[0046] Figure 2 shows a schematic representation of a retrofit device 1 installed in addition to an existing control system. The retrofit device 1 comprises a central control device 7 with an integrated microprocessor 9 for data processing and three switch heating devices 3, 3'. The central control device 7 is preferably installed near the existing control system 11, whereby the distance can be freely selected up to 1000 m.
[0047] The three switch heating devices 3, 3' are mounted on a switch. Preferably, two switch heating devices are mounted on each tongue and stock rail of a switch. A retrofit device 1 can have a plurality of switch heating devices 3, 3', and each
[0048] A point heating device is assigned to a specific heating category. A point heating device 3' is defined as the main point heating device 3'. Each point heating device 3, 3' comprises a heating element 4, a connection head 2 arranged on the heating element 4 with a local control unit 5 with an integrated microprocessor 13 and power switch 18, and a temperature sensor 6 arranged outside the connection head 2 and connected to the local control unit 5. The temperature sensor 6' of the main point heating device 3' is defined as the main temperature sensor 6' and is mounted directly next to, i.e. at a maximum distance of 10 cm from, the temperature sensor 10 of the existing control unit 11, so that the main temperature sensor 6' and the temperature sensor 10 of the existing control unit 11 measure the same temperature. Each point heating device 3, 3' is connected to a central control device 7 (in Fig.2 and 3). The temperature sensor 10 of the existing control system 11 is also connected to the existing control system via a bus line 15.
[0049] In this embodiment shown in Figure 2, the central control device 7 of the retrofit device 1 is directly connected to the existing controller 11 via a connection 16, such that signals at the output of the existing controller 11 can be tapped and routed to the central control device 7. For example, the existing controller 11 sends a signal to switch on the heating elements to an existing relay, which switches the power. This signal is rewired during the retrofit, away from the relay to the central control device 7. Since each point heating device 3, 3' has its own power switch 18, it can switch the power itself, and the existing relay is no longer required. By receiving the signal via the connection 16, the central control device 7 knows without delay when the existing controller 11 wants to switch on the heating.
[0050] In this way, signals that specify the switching on and off of the heating element on a predetermined rail with the temperature sensor 10 of the existing control system 11 can be detected and processed by the central control device 7. In this way, the retrofit device 1 recognizes how the existing control system 7 functions and what temperature setpoint specifications it has without knowing the existing control system 11 in detail.
[0051] In order to carry out the method according to the invention and to retrofit, control, monitor, distribute energy and selectively heat points in existing point heating systems, a retrofit device 1 is installed in addition to an existing point heating system and the following steps are carried out:
[0052] (A) several switch heating devices 3, 3' are attached to each switch as described in Figure 1, preferably two per stock rail and tongue rail, and in addition to an existing control 11, a central control device 7 is installed, the existing control 11 being connected to a temperature sensor 10 on a predetermined rail,
[0053] (B) the main temperature sensor 6' of a main switch heating device 3' and the temperature sensor 10 of the existing control 11 measure the same temperature;
[0054] (C) the microprocessor 9 of the central control device 7 detects a lower and upper temperature setpoint of the predetermined rail specified by the existing controller 11 by means of this previously defined main temperature sensor 6' and detects the information when the existing controller 11 gives the command to switch on and off the point heaters on the predetermined rail or when the point heaters on the predetermined rail switch on or off, and thus detects the functioning of the existing controller 11;
[0055] (D) the lower and upper temperature setpoint detected in step (C) or a predetermined lower and upper temperature setpoint is sent by the microprocessor 9 of the central control device 7 to the individual local control units 5 of each switch heating device (3, 3'), or the microprocessor 9 of the central control device 7 sends a command to the individual local control units 5 to switch the individual heating elements 4 on or off;
[0056] (E) the local control unit 5 of the switch heating device 3, 3' compares the detected or specified temperature setpoint with a value measured by the temperature sensor 6 at the respective switch heating device 3, 3' and switches the heating element 4 on when the lower temperature setpoint is undershot and switches the heating element 4 off when the upper temperature setpoint is exceeded, or follows a command to switch the individual heating elements 4 on or off without taking into account the previously specified temperature setpoint.
[0057] In addition, each local control unit 5 can be assigned a unique identification number (ID for short) 12 for each point heating device 3, 3'. Each of these unique IDs 12, and thus each point heating device 3, 3', can be assigned a heating category with a temperature setpoint, such that each point heating device 3, 3' can be assigned a different temperature setpoint. In one embodiment, the point heating devices 3, 3' at the switch point tip or at another exposed location on a switch are assigned to a first heating category and have a higher lower and upper temperature setpoint than the switch heating devices 3 that are mounted further away from the switch point tip and that are assigned to a second or further heating category. In the event of a power shortage or power grid overload, the point heating devices 3, 3' are switched off or switched on intermittently, or alternately switched on and off.
[0058] In one embodiment, the retrofit device 1 comprises a plurality of central control devices 7, 7' (7' not shown), wherein each of the plurality of central control devices 7, 7' is connected to a plurality of local control units 5 of the plurality of switch heating devices 3, 3', wherein the plurality of central control devices 7, 7' are interconnected via a bus connection as a network, wherein one of the central control devices 7 assumes the master role and the other central control devices 7' (not shown) assume the slave role, such that signals specified by the network can be sent to each local control unit 5 with an upper or lower temperature setpoint or with a command to switch the heating element 4 on or off, and wherein each local control unit 5 of the switch heating device 3, 3' is capable of regulating itself within the temperature specifications and switching itself on or off as needed.
[0059] Figure 3 shows a schematic representation of a retrofit device 1 as described in Figure 2, wherein the retrofit device 1 is also installed in addition to an existing control system and has a central control device 7 with an integrated microprocessor 9 for processing data and three switch heating devices 3, 3'. In contrast to the retrofit device 1 described in Figure 2, there is no connection between the central control device 7 of the retrofit device 1 and the existing
[0060] Control 11. For this purpose, the main switch heating device 3' is connected to the existing control 11 via a power line 14 and draws power from the existing control.
[0061] List of reference symbols
[0062] 1 retrofit device
[0063] 2 connection head
[0064] 3 Switch heating device
[0065] 3' main switch heating device
[0066] 4 heating element
[0067] 5 local control unit
[0068] 6 Temperature sensor
[0069] 6' main temperature sensor
[0070] 7, 7' central control device
[0071] 8 Bus line / radio connection
[0072] 9 Microprocessor of the central control device
[0073] 10 T emperature sensor of the existing control system
[0074] 11 existing control
[0075] 12 unique identification numbers (ID)
[0076] 13 Local control unit microprocessor
[0077] 14 Power line, connection of main switch heating device with existing control system
[0078] 15 Connection of existing control with temperature sensor
[0079] 16 Connection of existing control system with central control device
[0080] 17 Sensor cable
[0081] 18 circuit breakers
Claims
Patent claims 1. A method for retrofitting, controlling, monitoring and energy management of existing switch heating systems for the selective heating of switches for a rail-bound transport system, characterized by the following steps: (A) several switch heating devices (3, 3') are attached to each switch, each switch heating device (3, 3') comprising a heating element (4), a connection head (2) arranged on the heating element (4) with a local control unit (5) comprising a microprocessor (13) and a power switch (18), and a temperature sensor (6) arranged outside the connection head (2) and connected to the local control unit (5), and each local control unit (5) is connected by means of a bus line (8) and / or radio connection to a central control device (7) comprising a microprocessor (9), the central control device (7) being installed in addition to an existing control system (11), the existing control system (11) being connected to a temperature sensor (10) on a predetermined rail, (B) a switch heating device (3') is defined as the main switch heating device (3') and the temperature sensor (6') of this main switch heating device (3') is defined as the main temperature sensor (6'), wherein the main temperature sensor (6') of the main switch heating device (3') is mounted directly next to the temperature sensor (10) of the existing control system (11) so that the main temperature sensor (6') and the temperature sensor (10) of the existing control system (11) measure the same temperature; (C) the microprocessor (9) of the central control device (7) detects a lower and upper temperature setpoint of the predetermined rail specified by the existing control (11) by means of this previously defined main temperature sensor (6') and detects the information when the existing control (11) gives the command to switch on and off the switch heaters on the predetermined rail or when the switch heaters on the predetermined rail switch on or off; (D) the lower and upper temperature setpoint detected in step (C) or a predetermined lower and upper temperature setpoint is sent by the microprocessor (9) of the central control device (7) to the individual local control units (5) of each switch heating device (3, 3'), or the microprocessor (9) of the central control device (7) sends a command to the individual local control units (5) to switch the individual heating elements (4) on or off; (E) the local control unit (5) of the switch heating device (3, 3') compares the detected or specified temperature setpoint with a value measured by the temperature sensor (6) at the respective switch heating device (3, 3') and switches the heating element (4) on when the lower temperature setpoint is undershot and switches the heating element (4) off when the upper temperature setpoint is exceeded, or follows a command to switch the individual heating elements (4) on or off without taking the previously specified temperature setpoint into account.
2. Method according to claim 1, characterized in that the central control device (7) is connected to the existing control (11) and that between steps (B) and (C) the signals at the output of the existing control (11) are tapped and fed to the central control device (7).
3. Method according to claim 1 or 2, characterized in that each local control unit (5) of each switch heating device (3, 3') is assigned a unique address (12), and each of these unique addresses (12) and thus each switch heating device (3, 3') is assigned a heating category with a temperature setpoint, such that each switch heating device (3, 3') can be assigned a different temperature setpoint.
4. Method according to claim 3, characterized in that the Switch heating devices (3, 3') at the tip of the switch or at another exposed point of a switch are assigned to a first heating category and have a higher lower and upper temperature setpoint than the switch heating devices (3) which are mounted further away from the tongue tip on the switch.
5. Method according to claim 4, characterized in that the switch heating devices (3) which are not arranged at the tip of the tongue or an exposed point of a switch are assigned to a second heating category and have a lower temperature setpoint than the switch heating devices (3, 3') which are attached to the tip of the tongue on the switch.
6. Method according to claim 5, characterized in that the switch heating devices (3) of the second heating category are switched off in the event of a power shortage or power grid overload.
7. Method according to one of claims 4 or 5, characterized in that the switch heating devices (3) of the second heating category are switched on and off in a clocked manner in the event of a power shortage or power grid overload.
8. Method according to one of the preceding claims, characterized in that the microprocessor (9) of the central control device (7) collects all data and sends it to an external server for storage and optimization.
9. Retrofitting device (1) for an existing switch heating system, characterized in that the retrofitting device (1) comprises at least one central control device (7) and a plurality of switch heating devices (3, 3'), wherein a plurality of switch heating devices (3, 3') are each attached to a switch, wherein each switch heating device (3, 3') comprises a heating element (4), a connection head (2) arranged on the heating element (4) with an integrated local control unit (5), which comprises a microprocessor (13) and a power switch (18), and a temperature sensor (6) arranged outside the connection head (2) and connected to the local control unit (5), wherein the at least one central Control device (7) is connected to each individual local control unit (5) of the plurality of point heating devices (3, 3') by means of a bus line and / or radio connection (8), and wherein the central control device (7) comprises a microprocessor (9) for controlling, monitoring and for the energy management of point heaters (2), so that a local rail temperature can be measured via the temperature sensor (6) of a point heating device (3, 3') connected to the local control unit (5), which local rail temperature can be detected by the microprocessor (9) of the control device (7), wherein the microprocessor (9) can send signals to each local control unit (5) with an upper or lower temperature setpoint specification or with a command to switch the heating element (4 on or off), and wherein the local control unit (5) of the point heating device (3, 3') is capable of regulating itself within the temperature setpoint specifications.
10. Retrofit device (1) according to claim 9, characterized in that the retrofit device (1) comprises a plurality of central control devices (7, 7), wherein each of the plurality of central control devices (7, 7') is connected to a plurality of local control units (5) of the plurality of switch heating devices (3, 3'), wherein the plurality of central control devices (7, 7') are interconnected via a bus connection as a network, wherein one of the central control devices (7) assumes the master role and the other central control devices (7') assume the slave role, such that signals predetermined by the network can be sent to each local control unit (5) with an upper or lower temperature setpoint specification or with a command to switch the heating element (4 on or off), and wherein each local control unit (5) of the switch heating device (3, 3') is capable of regulating itself within the temperature specifications and switching itself on or off as required.
11. Retrofit device (1) according to one of claims 9 or 10, characterized in that the central control device (7) is installed in addition to an existing control (11), wherein the existing control (11) is connected to a temperature sensor (10) on a predetermined rail, wherein a temperature sensor (6') of a switch heating device (3') is used as Main temperature sensor (6') is defined and is mounted on a predetermined rail immediately next to the temperature sensor (10) of the existing control (11), so that the main temperature sensor (6') and the temperature sensor (10) of the existing control (11) measure the same temperature.
12. Retrofit device (1) according to one of claims 9 to 11, characterized in that each local control unit (5) of each switch heating device (3, 3') is assigned a unique address (12), and each unique address (12) and thus each switch heating device (3, 3') is assigned a heating category with a predetermined lower and upper temperature setpoint, such that each switch heating device (3, 3') can be assigned a different lower and upper temperature setpoint.
13. Retrofit device (1) according to one of claims 9 to 12, characterized in that the local control unit (5) comprises a processor for data processing and control of commands and processes.
14. Use of a retrofitting device (1) according to one of claims 9 to 13 for retrofitting existing switch heating systems.