Electrical system with fuse base and temperature sensor(s)

Abstract

Electrical installation with fuse base and temperature sensor(s), characterized in that the installation comprises the following: a fuse base which has at least one output terminal consisting of a metal plate, a distribution cable that is mechanically fastened and is in electrical contact with the metal plate by means of a terminal block, a socket made of electrically insulating material coupled to the terminal block and a temperature sensor which is mechanically attached to the terminal block via the socket and is in thermal contact with the plate and the electrical cable.

Description

SUBJECT OF THE INVENTION

[0001] One object of the invention is to provide an electrical system with a fuse base that enables the detection of hotspots in the connection area with the output cables of the fuse base.

[0002] Another objective of the invention is to provide a temperature monitoring system that can be easily installed in existing fuse holders, requires little space and does not require the power supply to be interrupted during the installation or removal of sensors. STATE OF THE ART

[0003] Energy monitoring devices are known to enable the monitoring of currents, voltages, power calculations, etc., thus facilitating better management of the distribution network. These modules are already widely used in distribution networks and are familiar to installers, who are already acquainted with them, their installation, and their use.

[0004] However, there is one area where improvement is needed and which has not yet been taken into account, namely the detection of hotspots that endanger the safety of the facilities and people and can be the cause of fires.

[0005] The main cause of fires in low voltage (LV) installations is a faulty electrical connection with poor electrical contact, which becomes a hotspot and can lead to a fire if flammable material is present nearby.

[0006] One of the most critical work processes is the connection of the output cables of the distribution lines, for example, when connecting to the output cables of a vertical fuse base, as described in Spanish patent ES-2,875,027 (T3). These connections are made on-site (in an uncontrolled environment), which is why an incorrectly made connection can lead to a hotspot and potentially a fire.

[0007] Furthermore, the overload of the distribution network due to increasing electricity demand means that the fuse holders are operating at or near their maximum capacity. If this condition persists, it can lead to undesirable situations such as fires. In other words, the fuses are operating at their rated current or with a slight overload, which, while still outside their melting point, nevertheless damages the system.

[0008] On the other hand, installing sensors in an existing fuse socket, i.e., a fuse socket already installed in a distribution box, presents the following difficulties: - there is little space available for the installation of sensors or other elements; - It may be necessary to disassemble some components of the fuse holder in order to install the sensor; - As a rule, the output cables must be disconnected, thus interrupting the power supply; The sensor to be connected to the fuse socket must be perfectly electrically insulated. The purpose is to monitor the temperature of conductors that are exposed live parts. If the temperature sensor touches the conductor, the sensor itself becomes live and would create an unsafe situation. However, materials that provide electrical insulation are generally poor heat conductors and thus contradict the functionality of the device. A balance must be found between electrical insulation and heat transfer. - Since the temperature sensors have a shorter lifespan than the switch on which they are installed, they usually need to be replaced during the lifespan of the switch, and their handling must be done with personal protective equipment and insulated tools. DESCRIPTION OF THE INVENTION

[0009] One aspect of the invention relates to an electrical system consisting of a conventional fuse base equipped with at least one output terminal in the form of a metal plate, and a distribution cable that is mechanically fastened and is in electrical contact with the metal plate by means of a terminal block.

[0010] According to the invention, the system comprises the following: a socket made of electrically insulating material coupled to the terminal block and a temperature sensor which is attached to the terminal block by means of the socket and is in thermal contact with the plate and the distribution cable in order to detect overheating in the connection between the two elements.

[0011] The terminal block can, for example, consist of a series of screws and nuts, leaving one screw with a free end. In this case, the socket has an internal thread at one end, allowing it to be screwed onto the free end of the screw. The temperature sensor is then attached to the screw via the socket, remaining in thermal contact with the plate and the electrical cable. The socket can be integrally formed with the thread embedded within the material, or the thread can be formed on a separate part, such as a metal component, and inserted into the socket.

[0012] In other versions, a different type of terminal block may be provided instead of a screw, in which case the socket has a design complementary to the shape of the terminal block in order to be coupled to it.

[0013] The other end of the socket is designed to allow the socket to be actuated with a tool in order to connect it to the terminal block. Preferably, the design of the other end is such that the socket can be screwed in by turning it with a suitable tool, for example, an Allen key or any screwdriver.

[0014] The temperature sensor can consist of, for example, a thermocouple or a thermistor, such as a PTC resistor (Positive Temperature Coefficient).

[0015] In a preferred embodiment, the temperature sensor consists of an annular metal clamp and an actual temperature sensor, which is in thermal contact with the annular metal clamp. The annular metal clamp surrounds the free end of the terminal block and is clamped in place by means of the socket.

[0016] The system includes an electronics module and a cable that connects the temperature sensor to the electronics module. The electronics module is designed to process the sensor's temperature measurements and communicate with an external device.

[0017] The fuse base contains a pre-installed terminal block or connector to which the temperature sensor(s) is / are internally connected.

[0018] Preferably, the fuse base is a vertical three-phase or three-pole fuse base, which has three output terminals, each in the form of a metal plate, and three distribution cables, each of which is individually connected to one of the plates. DESCRIPTION OF THE FIGURES Fig. 1. Shows a perspective view of the lower part of a conventional three-pole fuse base, with three distribution cables individually connected to the output terminals of the fuse base. Fig. 2. Shows a front view ( Fig. 2A), a side view ( Fig. 2B) and a perspective view ( Fig. 2C) of a system with a fuse base and temperature sensor(s) according to a further preferred embodiment of the invention. Fig. 2D shows a perspective view of a design with a floating connector attached to a terminal block of the fuse base. Fig. 3. Shows two perspective views of a magnified detail of the temperature sensor. Fig. 2, before the connection ( Fig. 3A) and after the connection ( Fig. 3B). Fig. 4. Shows a longitudinal section of the socket. Fig. 5. Shows a perspective view of a vertical three-pole fuse base, with the electronic module located at the top. PREFERRED EXECUTION OF THE INVENTION

[0019] The Fig. Figure 1 shows the lower part of a conventional three-phase or three-pole fuse base (1), which is equipped with three output terminals in the form of three plates (2a, 2b, 2c), each corresponding to one of the three phases of a three-phase electrical system. In operation, the three-pole fuse base (1) is part of an electrical installation (3) which further comprises three distribution cables (4a, 4b, 4c), each equipped with a terminal socket (5a, 5b, 5c) with an annular end (6a, 6b, 6c) by which they are mechanically fastened and electrically connected individually to each of the plates (2a, 2b, 2c) by means of corresponding screws (8a, 8b, 8c) and nuts (9a, 9b, 9c), as shown in Figure 1. Fig. 1 is shown.

[0020] An electrical system (3) according to a preferred embodiment of the invention is placed in the Fig. 2A - 2D shown and includes the one in the Fig. 1 fuse base (1) shown and three temperature sensors (18a, 18b, 18c) which are individually and mechanically connected to each ring (6a, 6b, 6c) to measure the temperature at the junction between each distribution cable (4a, 4b, 4c) and the plates (2a, 2b, 2c).

[0021] The system (3) further comprises three sockets (11a, 11b, 11c) made of electrically insulating material, each equipped with a recess (22a, 22b, 22c), an internal thread at one end and a connection with an internal thread (17a, 17b, 17c) to allow insertion of an Allen key and rotation of the socket (11a, 11b, 11c).

[0022] Each temperature sensor (18a, 18b, 18c) consists of an annular metal clamp (10a, 10b, 10c) and the actual temperature sensor (19a, 19b, 19c) which is in thermal contact with the annular metal clamp. The annular metal clamp (10a, 10b, 10c) is mounted around the free end of the screw (8a, 8b, 8c) and is clamped by the socket (11a, 11b, 11c).

[0023] The system (3) further comprises an electronic module (13) which, in the design of Fig. 2A - 2D is separated from the fuse base (1) and attached to one of the cables (4a) with a cable tie, and three cables (14a, 14b, 14c) connect each temperature sensor (18a, 18b, 18c) individually to the electronic module (13).

[0024] For example, in the Fig. As can be seen in 2A - 2C, the relative position of the temperature sensors is not fixed, so they can be installed in any fuse base model with different distances between the output terminals, requiring very little space and being very easy to install without having to cut the cables or interrupt the power supply.

[0025] During the execution of the Fig. In 2D, the fuse base (1) contains a pre-installed terminal block (21), and the system (3) has a floating connector (20) to which the cables (14a, 14b, 14c) of the temperature sensors (18a, 18b, 18c) are connected. In this case, the floating connector (20) is connected to the terminal block (21), but in other configurations, it can be connected to a different device as required.

[0026] Therefore, the temperature sensors (18a, 18b, 18c) terminate in a single connector, the floating connector (20), which is connected directly or via an intermediate adapter to processing electronics, so that the electronic module, which is thus arranged independently of the temperature sensors, can be replaced if necessary without having to disconnect the temperature sensors.

[0027] The mechanical and thermal connection of the temperature sensors to the connection point between cable and plate is described in the Fig. 3A, Fig. 3B clearly visible. Each plate (2a, 2b, 2c) has a hole through which the screw (8a, 8b, 8c) is passed, so that the cable ring (6a, 6b, 6c) is inserted into the screw on the outer surface of the plate, where it is fixed and held in contact by a washer (15a, 15b, 15c) and a nut (9a, 9b, 9c), leaving a section of the screw (8a, 8b, 8c) free, as shown in Fig. 3A is shown.

[0028] The ring-shaped metal clamp (10a, 10b, 10c) of the temperature sensors (18a, 18b, 18c), in this configuration a thermocouple, is inserted into this screw section (8a, 8b, 8c). The sensors are then pressed and held against the nut (9a, 9b, 9c) by means of the bushings (11a, 11b, 11c) screwed into the exposed part of the screw. In this way, the temperature sensor (18a, 18b, 18c) is in thermal contact with the connection point between the plate (2a, 2b, 2c) and the cable ring (6a, 6b, 6c) to detect any overheating at this critical point in the system.

[0029] The bushing (11a, 11b, 11c) is made of an electrically insulating material, has a cylindrical shape in this preferred embodiment according to the invention, has grooves (16a, 16b, 16c) on its outer surface to improve the grip and has an internal hexagon connection (17a, 17b, 17c) at its free end.

[0030] As in the cross-section of Fig. As shown in Figure 4, the bushing (11a, 11b, 11c) has a recess (22a, 22b, 22c) at one end with an internal thread, with which it is screwed onto the free end of the screw.

[0031] The socket (11a, 11b, 11c) enables the safe installation of the temperature sensors, as it is made of an insulating material and the connection (17a, 17b, 17c) is away from the live metal parts, thus preventing a tool, be it a screwdriver or an Allen key, from accidentally coming into contact with the metal parts.

[0032] As in Fig.As shown in Figure 5, the electronic module (13) can be installed on the upper part of the fuse base (1), and the wiring (14a, 14b, 14c) connecting the temperature sensors (18a, 18b, 18c) to the electronic module (13) runs inside the fuse base itself by means of a suitable channel or similar suitable means. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] ES 2.875.027

[0006]

Claims

[1] Electrical installation with fuse base and temperature sensor(s), characterized by , that the facility includes the following: a fuse base which has at least one output terminal consisting of a metal plate, a distribution cable that is mechanically fastened and is in electrical contact with the metal plate by means of a terminal block, a socket made of electrically insulating material coupled to the terminal block and a temperature sensor which is mechanically attached to the terminal block via the socket and is in thermal contact with the plate and the electrical cable. [2] Electrical installation with fuse base and temperature sensor(s) according to claim 1, characterized by that the terminal block is a screw with a free end and the socket has a recess with an internal thread at one end, by means of which it is screwed onto the free end of the screw. [3] Electrical installation with fuse base and temperature sensor(s) according to claim 2, characterized by that the other end of the socket is designed to be operated with a hand tool. [4] Electrical installation with fuse base and temperature sensor(s) according to claim 3, characterized by , that one end of the socket is designed to be turned using an Allen key or a screwdriver. [5] Electrical system with fuse base and temperature sensor(s) according to one of the preceding claims, characterized by , that the temperature sensor consists of an annular metal clamp and an actual temperature sensor which is in thermal contact with the annular metal clamp, the annular metal clamp surrounding the free end of the terminal block and being held by means of the socket. [6] Electrical system with fuse base and temperature sensor(s) according to one of the preceding claims, characterized by that the fuse base contains a terminal block or connector to which the temperature sensor(s) is / are connected. [7] Electrical system with fuse base and temperature sensor(s) according to one of the preceding claims, characterized by that it contains a floating connector to which the cables of the temperature sensor(s) are connected. [8] Electrical installation with fuse base and temperature sensor(s) according to claim 6, characterized by , that it contains an electronic module installed on the upper part of the fuse base, which is connected to the terminal block of the fuse base via conductors arranged inside the fuse base. [9] Electrical system with fuse base and temperature sensor(s) according to one of claims 1 to 6, characterized bythat it contains an electronic module separate from the fuse socket. [10] Electrical system with fuse base and temperature sensor(s) according to claim 8, characterized by that the electronic module is attached to one of the distribution cables. [11] Electrical installation with fuse base and temperature sensor(s) according to claim 2, characterized by that the bushing is a one-piece body made of a single material and the thread is made of this material. [12] Electrical system with fuse base and temperature sensor(s) according to claim 2, characterized by that the bushing contains a threaded metal body inserted into the recess.

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