CABLE PRESSURE BARRIER DEVICE, MANUFACTURING PROCESS FOR THE MANUFACTURE OF SAID DEVICE AND COMPRESSOR MOTOR LINE INCLUDING SAID DEVICE

Abstract

The invention relates to a cable pressure barrier device (6) fitted to a cable comprising an insulating sheath (3d) around a plurality of individually insulated wires (3e), a portion of said cable within the cable pressure barrier device is stripped of all insulation in order to expose the conductive core (6d1, 6d2) of each wire (6c1, 6c2) of the plurality of wires, the cable pressure barrier device (6) comprising a resin portion (6f) extending over a first portion (6d1) of the exposed conductive core of each wire connected to a first portion (3c1) of the cable by means of a first portion (6d1) of said wire, a second portion (6d2) of the exposed conductive core of each wire connected to a second portion (3c2) of the cable by means of a second portion (6c2) of said wire extending outside said resin portion (6f),the exposed conductive core of each wire and the resin portion (6f) being capable of interrupting the diffusion of a gas originating from the first part of the cable. Reference: Figure [Fig 3],

Description

Title of the invention: CABLE PRESSURE BARRIER DEVICE, MANUFACTURING PROCESS FOR MANUFACTURING SAID DEVICE AND MOTOR-COMPRESSOR LINE COMPRISING SAID DEVICE Technical field

[0001] The present invention relates to a sealing barrier for a cable connection, in particular for a cable connection in pressurized environments. State of the art:

[0002] A motor-compressor contains a compressor and a turbine in a single airtight enclosure reducing the risk of leaks. In some embodiments, the motor-compressor also includes a magnetic bearing or an AMB (acronym for "active magnetic bearing").

[0003] Such a motor-compressor is commonly used to pressurize explosive substances such as natural gas or hazardous gases such as carbon dioxide. In such applications, the motor-compressor operates with an internal pressure much higher than atmospheric pressure. Due to the hazardous gas involved, such a motor-compressor is usually placed in a restricted access area, such as an ATEX or HAZLOC zone. ATEX stands for "Atmosphère Explosible" in French and refers to a European directive on hazardous and explosive atmospheres. It is the European equivalent of the US HAZLOC standard. HAZLOC stands for "HAZardous LOCation" and is a US standard on hazardous and explosive atmospheres.

[0004] The control cabinets used for controlling such a motor-compressor are not located in a limited access area like the motor-compressor, but in a safe area according to the ATEX directive.

[0005] Figure [Fig.l] illustrates a motor-compressor ICL (acronym for "motor-compressor line") comprising a medium voltage junction box 1 connecting a control cabinet 2 to the motor-compressor 3. A first cable 2c connects the control cabinet 2 to the medium voltage junction box 1 and a second cable 3c connects the medium voltage junction box 1 to the motor-compressor 3.

[0006] Both the medium voltage junction box 1 and the motor-compressor 3 are located in an ATEX zone, while the control cabinet 2 resides in a safe zone as highlighted by reference 5.

[0007] Each cable 2c, 3c comprises an insulating sheath 2d, 3d and a plurality 2e, 3e of at least least two wires. Each 2c, 3c cable is ATEX class.

[0008] Such cables 2c, 3c are connected to the medium voltage junction box 1 and to the control cabinet 2 by means of cable glands 2a, 2f, 3f.

[0009] The control cabinet 2 is connected to the motor-compressor 3 via an ATEX class 3a, 3b connection. The ATEX class connection provides a first pressure barrier to gas diffusion through the electrical connection.

[0010] However, a total or partial failure of the connection 3a, 3b could lead to a gas leak in the second cable 3c. The gas could then diffuse along the cable 3b to the medium voltage junction box 1. The insulating sheath 3d would then behave like a conduit, channeling the gas from the connection 3a, 3b to the medium voltage junction box.

[0011] In such a case, there is a risk of gas accumulation in the medium voltage junction box 1, and of secondary gas diffusion along the first cable 2c to the control cabinet 2 in the safe zone.

[0012] Arrows designate the primary and secondary gas diffusions.

[0013] Such secondary diffusion would destroy the ATEX / HAZLOC zoning and would be a source of danger for personnel and the installation housing the motor-compressor.

[0014] In order to mitigate such a potential failure, both gas accumulation in the medium voltage junction box and secondary diffusion through the first cable 2c must be prevented.

[0015] A hood 4b and a gas detector 4c are commonly installed. In the event of gas diffusion through the second cable 3c, the gas accumulating within the medium voltage junction box 1 is purged via the breather valve 4a, and guided to the gas detector 4c by the hood 4b. As soon as the gas is detected, a signal is emitted, linked to an alarm and / or an emergency plan. Such an emergency plan may include stopping the motor-compressor 3 or informing the personnel in the premises about the incident.

[0016] It may be recognized that the triggering of such an alarm or such an emergency plan slows down or hinders the operation of the installation comprising the motor-compressor.

[0017] There is a need for a motor-compressor capable of mitigating any risk of gas diffusion while maximizing its operating time.

[0018] Documents GB1188286, DE2209629 and DE2440826 are known.

[0019] GB1188286 discloses a method for forming a gas seal in an electrical cable. The insulating sheath is removed and a porous material is added instead of the insulating sheath, allowing gases to diffuse out of the cable.

[0020] However, the described method does not disclose how to prevent gas from diffusing further into the cable beyond the gas seal.

[0021] Document DE2209629 and document DE2440826 disclose methods for sealing a cable after splitting. This document addresses the restoration of the integrity of the sheathing but says nothing about the diffusion of gases or a potential barrier to said diffusion.

[0022] The technical problem is not resolved by these documents. Summary :

[0023] An object of the invention is a cable pressure barrier device equipped on a cable comprising an insulating sheath around a plurality of individually insulated wires. The cable within the cable pressure barrier device is stripped of all insulation to expose a conductive core of each of the plurality of wires, the cable pressure barrier device comprising a resin portion extending over a first portion of the exposed conductive core of each wire connected to a first portion of the cable, a second portion of the exposed conductive core of each wire connected to a second portion of the cable extending outside said resin portion, the exposed conductive core of each wire and the resin portion being adapted to interrupt the diffusion of a gas from the second portion of the cable.

[0024] The cable pressure barrier device may comprise an enclosure equipped with a breather valve, the breather valve communicating with the interior of said enclosure comprising atmospheric air.

[0025] A comb may be installed and removably attached to the enclosure to keep the wires separated.

[0026] The plurality of wires may comprise at least two wires of at least two different gauges or diameters.

[0027] A comb may be installed and removably secured to the enclosure to keep the wires separated, said comb being able to accommodate different wire gauges by having different sized spacing between the teeth of the comb.

[0028] The comb may be placed over the exposed conductive core of the wires.

[0029] Two combs may be provided, each comb being installed on one side of the exposed conductive core of the wires.

[0030] The enclosure may comprise three parts, a first part corresponding to one half of the enclosure, extending from the first part of the cable to the second part of the cable, the other half of the enclosure being divided into a second part and a third part, the second part extending to the second part of the cable, the third part extending to the first part of the cable.

[0031] Another object of the invention is a motor-compressor line comprising a cable pressure barrier device as described above, in which the motor-compressor line comprises a medium voltage junction box connected to a control cabinet by a first cable and to a motor-compressor by a second cable, each cable comprising an insulating sheath around at least two individually insulated wires, the medium voltage junction box, the motor-compressor and the second cable being located in a hazardous or explosive atmosphere, the control cabinet and the first cable being located in a safe atmosphere, the cable pressure barrier device being installed on the second cable in order to mitigate a diffusion of gas, from the motor-compressor to the control cabinet via the medium voltage junction box.

[0032] Another object of the invention is a process for manufacturing a cable pressure barrier device as described above, comprising the following steps:

[0033] a. determining a suitable location for the cable pressure barrier device on the cable

[0034] b. at the determined location, removing the insulating sheath from the cable without cutting the wires contained within it,

[0035] c. for each wire exposed by removing the cable insulation, removing a portion of the wire insulation such that the conductive core is exposed,

[0036] d. inserting the cable through seals, provided on opposite faces of the first enclosure part, the cable residing inside each seal so that the cable between said two seals is free of its insulating sheath,

[0037] e. installing a second enclosure part to form a hermetic seal with the first enclosure part.

[0038] f. pouring a curable resin into the enclosure such that a first portion of the exposed conductive core of each wire is encased in resin together with each wire between said first portion of exposed conductive core and the first seal, said first seal being in contact with the cable extending from the cable pressure barrier device to the medium voltage junction box,

[0039] g. the curing of the resin.

[0040] Yet another object of the invention is a process for manufacturing a cable pressure barrier device as described above comprising a three-part enclosure, comprising the following steps:

[0041] a. determining a suitable location for the cable pressure barrier device on the cable,

[0042] b. at the determined location, removing the insulating sheath from the cable without cutting the wires contained within it,

[0043] c. for each wire exposed by removing the cable insulation, removing a portion of the wire insulation such that the conductive core is exposed,

[0044] d. inserting the cable through seals provided on opposite faces of the first enclosure part, the cable residing within each seal such that the cable between said two seals is free of its insulating sheath,

[0045] e. installing a second enclosure part so as to achieve a hermetic seal with the first enclosure part,

[0046] f. pouring a curable resin into the enclosure such that a first portion of the exposed conductive core of each wire is encased in resin together with each wire between said first portion of exposed conductive core and the first seal, said first seal being in contact with the cable extending from the cable pressure barrier device to the medium voltage junction box,

[0047] g. curing the resin and then installing a third enclosure part so as to achieve a hermetic seal with both the first enclosure part and the second enclosure part. Brief description of the drawings

[0048] The present invention will be better understood upon studying the detailed description of a certain number of embodiments considered as entirely non-limiting examples and illustrated by the appended drawing in which:

[0049] [Fig. 1] represents a motor-compressor comprising a medium voltage junction box having a breather valve and a detector,

[0050] [Fig.2] represents a motor-compressor comprising a barrier device to the pressure on cable according to the invention,

[0051] [Fig.3] represents the main components of a cable pressure barrier device,

[0052] [Fig.4] represents the main components of a pressure barrier device on cable including a comb and

[0053] [Fig.5] shows the main parts of a cable pressure barrier device enclosure. Description of the embodiments

[0054] Figure [Fig.2] illustrates a motor-compressor according to the invention. The elements in common with the control system illustrated by Figure [Fig.l] bear the same references.

[0055] The motor-compressor comprises a medium voltage junction box 1 connecting a control cabinet 2 to the motor-compressor 3. A first cable 2c connects the control cabinet 2 to the medium voltage junction box 1 and a second cable 3c 1, 3c2 connects the medium voltage junction box 1 to the motor-compressor 3. The first cable 2c and the second cable 3c 1, 3c2 are connected together by means of a connection plate 1a included within the medium voltage junction box 1.

[0056] Both the medium voltage junction box 1 and the motor-compressor 3 are in an ATEX zone, while the control cabinet 2 is in a safe zone such as underlined by reference 5.

[0057] Each cable 2c, 3c 1, 3c2 comprises an insulating sheath 2d, 3d and a plurality 2e, 3e of wires. Each cable is ATEX class.

[0058] The medium voltage junction box comprises a first cable gland 2f through which the first cable 2c is connected to the control cabinet 2. The control cabinet 2 comprises its own cable gland 2a through which the first cable 2c is connected.

[0059] The medium voltage junction box comprises a second cable gland 3f through which the second cable 3c 1, 3c2 is connected.

[0060] The control cabinet 2 is connected to the motor-compressor 3 via an ATEX class 3a, 3b connection.

[0061] In a similar manner to the risk of gas diffusion described in relation to the control system illustrated in Figure [Fig.l], a risk of gas diffusion through the second cable 3c 1, 3c2 from the motor-compressor 3 to the medium voltage junction box 1 exists, even when ATEX class 2c, 3c 1, 3c2 cables and ATEX class 3a, 3b fittings are used.

[0062] In order to avoid such gas diffusion and any consequences (gas accumulation in the medium voltage junction box 1 or further diffusion through the first cable 2c), a cable pressure barrier device 6 is provided on the second cable 3c1, 3c2. More specifically, a first portion 3c1 of the second cable connects the medium voltage junction box 1 to the cable pressure barrier device 6. A second portion 3c2 of the second cable connects the cable pressure barrier device 6 to the motor-compressor 3. Although two portions 3c1, 3c2 are cited, the second cable 3cl, 3c2 is not interrupted during the installation of the cable pressure barrier device 6, as will become clear from the present description.

[0063] Figure [Fig.3] illustrates the main components of a cable pressure barrier device 6 according to the invention. The cable pressure barrier device 6 is particularly advantageous due to the fact that its installation does not require the carrier cable 3cl, 3c2 to be interrupted (i.e. the wires included in the second cable 3c1, 3c2 to be kept intact during installation).

[0064] The cable pressure barrier device 6 comprises an enclosure 6a, a breather valve 6b, two seals 6g, 6h, and a resin part 6f.

[0065] The enclosure 6a is designed so that it can be opened into at least two parts in order to be placed on the second cable 3c 1, 3c2.

[0066] The second cable 3c 1, 3c2 is fixed in the enclosure 6a by means of the seals 6g, 6h, which at the same time allows the enclosure 6a to be gas-tight.

[0067] The second cable 3c 1, 3c2 included within the enclosure 6a is stripped of its sheath insulating 3d. Therefore, the at least one wire 6c 1, 6c2 included in the plurality 3e of wires within the second cable 3c 1, 3c2 is loose within the enclosure 6a.

[0068] In order for the cable pressure barrier device 6 to acquire its barrier properties, each wire 6c 1, 6c2 is stripped of a portion of its own insulating sheath so that its conductive core 6dl, 6d2 is exposed. Within the cable pressure barrier device 6, each wire comprises a first portion 6c 1 with its insulating sheath, a first portion of exposed conductive core 6dl, a second portion of exposed conductive core 6d2 and a second portion 6c2 with its insulating sheath. Although two portions 6c 1, 6c2 for each wire are cited, the wires 6c 1, 6c2 and their exposed conductive core 6dl, 6d2 are not interrupted during installation of the cable pressure barrier device 6 as will be apparent from the present description.

[0069] A resin portion 6f is then formed in the enclosure 6a so that it covers a first portion 6dl of the exposed conductive core of each wire 6c 1, 6c2 together with a first portion 6c 1 of each wire up to the first joint 6g through which a first portion 3c 1 of the second cable passes. The resin portion 6f extends in the other directions up to the enclosure 6a.

[0070] The remaining portion of the enclosure is kept free of any resin and comprises a second portion 6d2 of the exposed conductive core of each wire together with a second portion 6c2 of each wire up to the second joint 6h through which a second portion 3c2 of the second cable passes.

[0071] In the case of gas diffusion within the insulating sheath 3d of the second part 3c2 of the second cable, the gas is released within the enclosure 6a through the second part 6d2 of the exposed conductive core of each wire extending outside the resin part 6f.

[0072] However, due to the mating contact between the resin portion 6f, the first portion 6dl of each exposed conductive core and the first portion 6c 1 of each wire, the gas diffusion cannot spread further, in particular along the first portion 3c 1 of the second cable and the first portion 6dl of each wire. The gas is then purged by the breather valve 6b.

[0073] It is therefore understood that the internal volume of said enclosure 6a comprises either atmospheric air or at least one gas, in the event of a gas leak inside the box, or a mixture of atmospheric air and at least one gas. Said atmospheric air, at least one gas or mixture of atmospheric air and at least one gas inside the enclosure, have a pressure corresponding to, comparable to, or around the atmospheric air pressure. In a preferred embodiment, said atmospheric air, at least one gas or mixture of atmospheric air and at least one gas inside the enclosure, have a pressure equal to the pressure of atmospheric air. An object of the present invention is to provide an internal volume of said enclosure not under pressure relative to the external air atmosphere, thanks to the breather valve 6b.

[0074] In order to fully understand the operation of the pressure barrier device on cable 6, it is important to recall the fundamental laws of diffusion.

[0075] A gas diffusion occurs when a pressure difference exists between two zones which are connected. In the present application, the motor-compressor 3 is included within a housing in which a gas is under pressure. The motor-compressor 3 must be supplied with energy and controlled, which implies the presence of at least one cable 3c 1, 3c2. The cable 3c 1, 3c2 is connected by means of an ATEX class connector as stated previously. This connector is designed so that it forms a first pressure barrier against a gas diffusion.

[0076] However, in some cases, this first pressure barrier may fail and gas may still diffuse through both the second cable sheath 3d and each individual wire insulation sheath 6c1, 6c2, both then acting as conduits. Upon reaching the on-cable pressure barrier device 6, the second cable sheath 3d is interrupted at the second joint 6h. Any gas diffusing through the second cable sheath 3d then diffuses either into the atmosphere around the joint or within the on-cable pressure barrier device enclosure 6a.

[0077] Similarly, upon reaching the cable pressure barrier device 6, each wire insulating sheath is interrupted at the exposed core portion 6dl, 6d2.

[0078] Any gas diffusing through a wire insulating sheath then diffuses within the enclosure 6a of the cable pressure barrier device.

[0079] In both cases, any gas that diffuses within the cable pressure barrier device enclosure 6a is then purged into the ATEX atmosphere via the breather valve 6b. The breather valve 6b is used to maintain the pressure within the enclosure 6a at an atmospheric level. As a result of this purging, a buildup of gas within the enclosure 6a is prevented. Finally, due to the coupling between the resin portion 6f, the first portion 6dl of the exposed conductive core of each wire, and the enclosure 6a, there is no passage for further gas diffusion. The pressure is also kept low by means of the breather valve 6b, further preventing gas diffusion.

[0080] It becomes apparent that the cable pressure barrier device 6 can be considered as a second pressure barrier against gas diffusion originating from the motor-compressor 3.

[0081] In some embodiments, there is a risk of short circuiting or arcing between the wires 6cl, 6c2 after exposure of their conductive cores 6dl, 6d2. In order to keep the exposed conductive cores 6dl, 6d2 separate, the comb 6e is then installed and removably secured to the enclosure 6a, as illustrated in Figure [Fig.4]. The comb 6e is of course made from a non-conductive material. An additional advantage of the comb 6e is to facilitate the curing of the resin portion 6f, by giving a visual indication of the amount of resin to be poured, particularly when the comb 6e is placed over the exposed conductive core 6dl, 6d2 of the wires. When the comb 6e is used as such a visual indicator, it is located between the first portion 6dl and the second portion 6d2 of the exposed conductive core of each wire 6c 1, 6c2. It should be noted that the 6th comb can be removed before a curable resin is poured and cured.After the resin has hardened, the comb is embedded in the resin part 6f and can no longer be removed.

[0082] In other embodiments, the comb 6e may be placed further from the exposed conductive core 6dl, 6d2 of the wires, on wires 3c 1, 3c2 still including their insulating sheaths, as long as the exposed conductive core portions 6dl, 6d2 are kept at an appropriate distance from each other to mitigate the risks of short circuiting and arcing. In still other embodiments, two combs may be provided, either on the exposed conductive core portions 6dl, 6d2 of the wires, or one on each side of the exposed core portions 6dl, 6d2 of the wires.

[0083] In some additional embodiments, the wires 6c1, 6c2 are of at least two different gauges or diameters. The at least one comb 6e is able to accommodate the different gauges of wire thanks to a different spacing between the teeth, forming openings of different size.

[0084] It should be noted that the continuity of the second cable 3c 1, 3c2 is not altered by the installation of the cable pressure barrier device 6. The first part 3c 1 and the second part 3c2 of the second cable are simply intended to name the parts of the second cable on one side and the other of the cable pressure barrier device 6.

[0085] A manufacturing process for a cable pressure barrier device will now be described. The manufacturing process comprises the following steps.

[0086] During a first step, the location of the pressure barrier device on cable 6 is determined on the second cable 3c 1, 3c2 connecting the medium voltage junction box 1 to the motor-compressor 3.

[0087] At the determined location, the insulating sheath 3d of the second cable 3c 1, 3c2 is removed over a length of cable equal to the length of the enclosure 6a of the cable pressure barrier. The insulating sheath 3d is removed without cutting the wires 6c 1, 6c2 included within it.

[0088] Each individual wire 6c 1, 6c2 comprised in the second cable 3c 1, 3c2 is then separated and extended. A limited portion of each wire 6c 1, 6c2 is stripped of its insulating sheath so that the conductive core 6dl, 6d2 is exposed.

[0089] During a second step, the second cable 3c 1, 3c2 is inserted through joints 6g, 6h in a manner that allows the joints 6g, 6h to each be placed at a location where the insulating sheath 3d ends after removal of a portion during the first step of the manufacturing process. The second joint 6h is located on the motor-compressor 3 side, the first joint 6g being located on the medium voltage junction box side.

[0090] The seals 6g, 6h are provided in a first part of the enclosure 6a.

[0091] A second enclosure part 6a is then sealed with the first enclosure part 6a.

[0092] A curable resin, in particular PU (acronym for "Polyurethane") is poured into the enclosure to fill the enclosure such that a first exposed conductive core portion 6dl of each wire 3c 1, 3c2 is partially enclosed in the resin together with a first portion 3c 1 of each wire portion between said first exposed conductive core portion 6dl and the first joint 6g.

[0093] In a particular embodiment, at least one comb 6e is removably attached to the enclosure before pouring the curable resin.

[0094] The resin may be either a UV curable resin or a thermosetting resin, the latter being preferred because heat may be applied through the enclosure. It should be understood that once the resin is cured, the at least one 6th comb is no longer removable.

[0095] The enclosure 6a has been described as comprising at least two parts. However, a three-part enclosure is preferred. Figure [Fig.5] illustrates a three-part enclosure 6a.

[0096] A first part 6al corresponds to half of the enclosure 6a, extending from the first joint 6g to the second joint 6h.

[0097] The other half of the enclosure is divided into a second part 6a2 and a third part 6a3.

[0098] During the manufacturing process, the second portion 6a2 is placed before pouring the curable resin. The first portion 6a1 and the second portion 6a2 then form a container into which the curable resin can be poured through the opening corresponding to the location of the third portion 6a3. In one embodiment, the second half of the enclosure is extended between the second portion 6a2 and the third portion 6a3 so that the second portion covers at least the entirety of the resin portion 6f. This is advantageous because it reduces the chances of the curable resin flowing outside the enclosure 6a as it is poured.

[0099] Once the resin is hardened, the third part 6a3 of the enclosure 6a is sealed with the first part 6a1 and the second part 6a2.

[0100] It should be recognized that Figures [Fig.3], [Fig.4] and [Fig.5] show the breather valve 6b on the same side as that on which the second seal 6h is installed. However, the breather valve 6b is advantageously installed so that it is located in the part of the enclosure where any accumulation of gas is likely to occur.

[0101] If the density of the gas considered is greater than the density of the atmosphere surrounding the cable pressure barrier device 6, it is more advantageous to position the breather valve 6b in the highest part of the enclosure 6a.

[0102] If the density of the gas considered is lower than the density of the atmosphere surrounding the pressure barrier device on cable 6, it is more advantageous to position the breather valve 6b in the lowest part of the enclosure 6a.

[0103] The cable pressure barrier device has been described in connection with a motor-compressor in a motor-compressor line. However, it is clear that the cable pressure barrier can be used on any cable connected to a pressurized environment, which could be subject to gas migration.

[0104] The motor-compressor line and the pressure barrier device on the cable allow attenuation of gas diffusion in the event of a leak in the ATEX connection of the motor-compressor. List of references:

[0105] 1: medium voltage junction box

[0106] the: connection plate

[0107] 2: control cabinet

[0108] 2a: control cabinet cable gland

[0109] 2c: first cable

[0110] 2d: insulating sheath of first cable

[0111] 2nd: plurality of at least two wires within the first cable

[0112] 2f: first stuffing box

[0113] 3: motor-compressor

[0114] 3 a, 3b: ATEX connection

[0115] 3c, 3cl, 3c2: second cable

[0116] 3d: insulating sheath of second cable

[0117] 3rd: plurality of at least two wires within the second cable

[0118] 3f: second stuffing box

[0119] 4a: breather valve

[0120] 4b: hood

[0121] 4c: gas detector

[0122] 5: boundary between ATEX zone and safe zone

[0123] 6: pressure barrier device on cable

[0124] 6a: enclosure

[0125] 6al: first part of enclosure

[0126] 6a2: second part of enclosure

[0127] 6a3: third part of enclosure

[0128] 6b: breather valve of the pressure barrier device on cable

[0129] 6c, 6cl, 6c2: wire included in the plurality of second cable wires

[0130] 6d, 6dl, 6d2: conductive core of a wire

[0131] 6th: comb

[0132] 6f: resin part

[0133] 6g: first seal

[0134] 6h: second seal

Claims

Claims

1. A cable pressure barrier device (6) provided on a cable (3c 1, 3c2) comprising an insulating sheath (3d) around a plurality of individually insulated wires (3e), characterized in that the cable (3c 1, 3c2), within the cable pressure barrier device (6), is stripped of all insulation to expose a conductive core (6dl, 6d2) of each wire (6c 1, 6c2) of the plurality of wires, the cable pressure barrier device (6) comprising a resin portion (6f) extending over a first portion (6dl) of the exposed conductive core of each wire connected to a first portion (3c 1) of the cable via a first portion (6dl) of said wire, a second portion (6d2) of the exposed conductive core of each wire connected to a second portion (3c2) of the cable via the bias of a second part (6c2) of said wire extends outside of said resin part (6f),the exposed conductive core of each wire and the resin portion (6f) preventing the diffusion of a gas from the second portion (3c2) of the cable.,

2. A cable pressure barrier device according to claim 1, wherein the cable pressure barrier device (6) comprises an enclosure (6a) equipped with a breather valve (6b), the breather valve (6b) communicating with an internal volume of said enclosure (6a) comprising atmospheric air.

3. A cable pressure barrier device according to claim 1 or 2, wherein a comb (6e) is removably attached to the enclosure (6a) to keep the wires separated.

4. A cable pressure barrier device according to claim 1 or 2, wherein the plurality of wires comprises at least two wires of at least two different gauges or diameters.

5. A cable pressure barrier device according to claim 4, wherein a comb (6e) is removably attached to the enclosure (6a) to keep the wires separated, said comb (6e) comprising at least two teeth between which a wire is inserted, the comb (6e) being able to accommodate different gauges of wire thanks to a variable spacing between the teeth.

6. A cable pressure barrier device according to claim 3 or 5, wherein the comb (6e) is placed on the exposed conductive core (6dl, 6d2) of the wires.

7. Cable pressure barrier device according to either of the re- claims 3, 5 or 6, wherein two combs are provided, each comb being installed on one side of the exposed conductive core (6dl, 6d2) of the wires.

8. A cable pressure barrier device according to any one of claims 1 to 7, wherein the enclosure (6a) comprises three parts, a first part (6al) corresponding to one half of the enclosure (6a), extending from the first part (3c 1) of the cable to the second part (3c2) of the cable, the other half of the enclosure (6a) being divided into a second part (6a2) and a third part (6a3), the second part (6a2) extending to the second part (3c2) of the cable, the third part (6a3) extending to the first part (3cl) of the cable.

9. A motor-compressor line comprising a cable pressure barrier device (6) according to any one of claims 1 to 8, wherein the motor-compressor line comprises a medium voltage junction box (1) connected to a control cabinet (2) by a first cable (2c) and to a motor-compressor (3) by a second cable (3c 1, 3c2), each cable (2c, 3c 1, 3c2) comprising an insulating sheath (2d, 3d) around at least two individually insulated wires (2e, 3e), the medium voltage junction box (1), the motor-compressor (3) and the second cable (3c 1, 3c2) being located in a hazardous or explosive atmosphere, the control cabinet (2) and the first cable (2c) being located in a safe atmosphere, the cable pressure barrier device (6) being installed on the second cable (3c 1, 3c2) in order to mitigate gas diffusion,from the motor-compressor (3) to the control cabinet (2) via the medium voltage junction box (1).,

10. A process for manufacturing a cable pressure barrier device as described in claims 1 to 7, comprising the steps of: a. determining a suitable location for the cable pressure barrier device (6) on the cable (3c 1, 3c2), b. at the determined location, removing the insulating sheath (3d) from the cable without cutting the wires (6c 1, 6c2) included therein, c. for each wire (6c 1, 6c2) exposed by removing the insulating sheath (3d) from the cable, removing a portion of the wire insulating sheath so that the conductive core (6dl, 6d2) is exposed, d. inserting the cable through gaskets (6g, 6h) provided on opposite faces of the first enclosure part, the cable residing inside each gasket (6g, 6h) such that the cable (3c 1, 3c2) between said two gaskets (6g, 6h) is at least partially free of its insulating sheath, e. installing a second enclosure part (6a2) in order to form a hermetic seal with the first enclosure part (6al), f. pouring a curable resin into the enclosure (6a) such that a first portion (6dl) of the exposed conductive core of each wire is embedded in resin together with the first portion (6c 1 ) of each wire between said first portion of exposed conductive core (6dl) and the first seal (6g), said first seal (6g) being in contact with the first portion (3c 1 ) of the cable extending from the cable pressure barrier device (6) to the medium voltage junction box (1), g. curing of the resin.

11. A process for manufacturing a cable pressure barrier device as described in claim 8, comprising the following steps: a. determining a suitable location for the cable pressure barrier device (6) on the cable, b. at the determined location, the removal of the insulating sheath (3d) of the cable without cutting the wires (6c 1, 6c2) included within it, c. for each wire (6c 1, 6c2) exposed by removing the insulating sheath (3d) from the cable, removing a portion of the wire insulating sheath so that the conductive core (6dl, 6d2) is exposed, d. inserting the cable through seals (6g, 6h) provided on opposite faces of the first enclosure part, the cable residing inside each seal (6g, 6h) such that the cable between said two seals (6g, 6h) is at least partially free of its insulating sheath, e. the installation of a second enclosure part (6a2) so as to achieve a hermetic seal with the first part enclosure (6al), f. pouring a curable resin into the enclosure (6a) such that a first portion (6dl) of the exposed conductive core of each wire is embedded in resin together with the first portion (6c 1) of each wire between said first portion of exposed conductive core (6dl) and the first seal (6g), said first seal being in contact with the first portion (3cl) of the cable extending from the cable pressure barrier device (6) to the medium voltage junction box (1), g. curing the resin and then installing a third enclosure part (6a3) so as to achieve a hermetic seal with both the first enclosure part and the second enclosure part.

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