Surge protector with isolation gap in the base

Abstract

This is a surge protector with an isolation gap in a U-shaped base 1 comprising earth terminals 5 and phase terminals 4 and at least two replaceable protection modules 2 with contacts to be inserted into the holes of the pins 3 of the phase terminals 4 and into the holes of a jumper 7 to which one end of the isolation gap 6 is electrically connected, the other end of the isolation gap 6 being connected by a strip 8 and / or a screw and / or a solder to at least one earth terminal 5, characterized in that the axis 10 of the isolation gap 6 is perpendicular to the upper surface of the jumper 7.

Description

Title of the invention: Surge protector with isolation spark gap in the base Field of the invention

[0001] The invention relates to protection against the effects of overvoltage of equipment including devices and their components which use the electrical network for their function, preferably electrical equipment and devices connected to the computer electrical network. Background of the invention

[0002] In places where high operational reliability is required, such as operating rooms and intensive care units in hospitals, military defense systems, mines, metallurgical plants, etc., isolated electrical networks are used to power electrical and electronic devices. To protect these devices, surge arresters with replaceable protection modules containing metal oxide varistors are necessarily installed. These voltage-dependent protection elements have a constant leakage current that increases over time and can affect the operation of the protected devices. The common node of the exchangeable modules is therefore not connected directly to the protective earth, but via a suitable isolation spark gap.

[0003] Known products are described in numerous publicly available non-patent documents from a number of surge protector manufacturers. All of these products have an isolation spark gap located in another exchangeable module. The disadvantage of this solution is that the device is larger and takes up unnecessary space in the distribution board and, for large systems, it is necessary to choose a larger, i.e. more expensive, distribution board.

[0004] As regards patent documents, a similar solution is described, for example, in EP 1587188. The invention relates to a surge protection device for the protection of low-voltage electrical systems, consisting of a lower part with terminals for the phase conductors (L1, L2, L3) and a neutral conductor (PE, N) and several plug-in modules containing a varistor-type surge protection component. The isolation spark gap can be placed in one of the plug-in modules.

[0005] A similar technical solution disclosed in document DE 202004005491 relates to a surge protection device for the protection of low-voltage electrical systems, consisting of a lower part with terminals for the phase conductors (Ll, L2, L3) and an earthing conductor or neutral conductor (PE, N) and at least one surge protection component with a limiting device, usually a surge arrester and / or surge protector, in a plug-in module.

[0006] Other well-known commercially available solutions use single-pole protection components connected as a single unit via external conductors. The disadvantage of requiring additional space in the distribution board remains. A significant disadvantage of these solutions is that the interconnecting conductors increase the protection level by their inductance and the connected devices are therefore subject to a higher residual overvoltage. Summary of the invention

[0007] The invention overcomes the above-mentioned drawbacks to a large extent by providing a surge protector with an isolation gap comprising a U-shaped base with earth terminals and phase terminals and at least two replaceable protection modules with contacts to be inserted into the holes of the pins of the phase terminals and into the holes of the jumper to which one end of the isolation gap is electrically connected. In particular, the isolation gap is in the U-shaped base. The essence of the invention is that the other end of the isolation gap is electrically connected by a strip and / or a screw and / or a solder to at least one earth terminal, the axis of the isolation gap being perpendicular to the upper surface of the jumper.

[0008] According to a preferred embodiment, the isolation spark gap is formed by a voltage-dependent non-linear switching element. The voltage-dependent non-linear element is preferably a surge arrester and more preferably a gas-filled surge arrester.

[0009] According to an advantageous embodiment, a resistor is connected in parallel to the isolation spark gap, its resistance being in the range from 3MΩ to 4MΩ. The resistor is connected to the isolation spark gap parallel to its axis. According to another advantageous embodiment, a capacitor with a capacitance value in the range from 0.5nF to 3nF is connected in parallel to the isolation spark gap.

[0010] The electrical connection between the insulation gap, the jumper and the strip may be formed by an electrically conductive connection, for example a screw, solder or the like.

[0011] The strip can be adapted as required to facilitate mounting to the grounding terminals. In an advantageous embodiment, the strip is part of the isolation gap. The strip then forms a single unit with the isolation gap.

[0012] In an even more advantageous embodiment, the bar is part of the earth terminal. Brief description of the drawings

[0013] The invention will be explained in more detail with respect to a specific example of embodiment with the aid of the figures, in which

[0014] [Fig-1] shows a surge protector with three replaceable modules with elements protection, a base with three phase terminals, two earth terminals and an integrated isolation spark gap which is hidden under the top cover.

[0015] [Fig.2] shows the base of the surge protector without the top cover, with three phase terminals, three phase terminal pins, one jumper, two ground terminals with a mounted bar and an integrated isolation spark gap.

[0016] [Fig.3] shows another view of the base of the surge protector without the cover upper. [Fig.4] shows an advantageous embodiment of the electrically conductive welded connection of the strip and the insulating spark gap forming a unit.

[0017] [Fig.5] shows the base with the space created for the isolation spark gap and the bar forming part of the earth terminal.

[0018] [Fig.6] shows the protection module with two protruding contacts.

[0019] [Fig.7] shows the electrical diagram of the surge protector connected in accordance with this document. Examples of embodiments of the invention

[0020] An example of a surge protection device with an insulating spark gap integrated in the base is shown in axonometric perspective in [Fig.l]. The surge protection device comprises a U-shaped base 1, adapted on the lower side to be mounted on a DIN rail, and several replaceable protection modules 2 whose contacts are inserted into the holes of the pins 3 by which they are electrically connected to the phase terminals 4 generally located on the upper arm of the U-shape to allow the connection of the surge protection device to the phase conductors L1, L2 and L3.The opposite contacts of the replaceable protection modules 2 are inserted into the holes of the jumper 7 which is electrically connected to one end of the insulation gap 6, the second end of which is electrically connected via the strip 8 to at least one earth terminal 5 for the protective earth conductor and located in the lower arm of the U-shape, the axis 10 of the insulation gap 6 being perpendicular to the upper surface of the jumper 7.

[0021] The electrically conductive connection between the insulation gap 6, the jumper 7 and the strip 8 is advantageously made by means of a screw connection and is shown in Figures 2, 3 and 5.

[0022] In another embodiment illustrated in [Fig.4], the strip 8 is connected to the insulation spark gap 6 by welding.

[0023] The insulating spark gap 6 is generally formed by a gas lightning arrester under a protective atmosphere, provided for this purpose with screw terminals and / or surfaces to be welded at each end.

[0024] The isolation spark gap 6 may also be formed by voltage-dependent non-linear switching elements which operate according to the principle of electrical discharge in an environment without a protective atmosphere, generally consisting of two or more electrodes in an insulating housing, possibly supplemented by the inclusion of electronic circuits allowing controlled triggering of the spark gap.

[0025] Within the scope of the present invention, the embodiments described above are collectively referred to as isolation spark gaps, without the invention being limited to a specific type of isolation spark gap.

[0026] In the embodiment of the surge protector 1 shown in the figures, the phase terminals 4 and the ground terminals 5 are designed as screw terminals. However, the phase terminals 4 and the ground terminals 5 can also be designed without screw terminals which are also called spring terminals or spring cage terminals. In these terminals, the conductor is held by the pressure of the spring instead of the pressure generated by the screw.

[0027] The protection module 2 generally comprises a varistor-based protection element. A series circuit combination with the varistor and the gas-filled surge arrester or the controlled spark gap is also applicable. Industrial application

[0028] The surge protector with an integrated isolation spark gap in the base can be used to protect electrical equipment and devices or their components connected to the power grid against the effects of surges in places where high operational reliability is required, such as operating rooms and intensive care units in hospitals, military defense systems, mines, metallurgical plants, etc. while providing significant savings in terms of investment costs.

[0029] It will be understood that the present invention is defined by the claims. Accordingly, it is not limited to the examples and embodiments described and shown, but is susceptible of numerous variations falling within the scope of the protection conferred by the claims.

Claims

Claims

1. Surge protector with an isolation gap in a U-shaped base (1) comprising earth terminals (5) and phase terminals (4) and at least two replaceable protection modules (2) with contacts to be inserted into the holes of the pins (3) of the phase terminals (4) and into the holes of a jumper (7) to which one end of the isolation gap (6) is electrically connected, the other end of the isolation gap (6) being connected by a strip (8) and / or a screw and / or a solder to at least one earth terminal (5), characterized in that the axis (10) of the isolation gap (6) is perpendicular to the upper surface of the jumper (7).

2. Surge protector according to claim 1, wherein the isolation spark gap (6) is formed by a voltage-dependent non-linear switching element.

3. A surge protector according to claim 2, wherein the voltage-dependent nonlinear element is a surge arrester.

4. A surge protector according to claim 3, wherein the surge protector is of the gas type.

5. A surge protector according to any one of claims 1 to 4, wherein a resistor (9) is connected in parallel to the isolation gap (6), its resistance being in the range of 3MΩ to 4MΩ, and / or a capacitor with a capacitance value in the range of 0.5nF to 3nF is connected in parallel to the isolation gap (6).

6. A surge protector according to any one of claims 1 to 5, wherein the strip (8) is part of the isolation gap (6).

7. A surge protector according to any one of claims 1 to 5, wherein the strip (8) forms part of the earth terminal (5).

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