TEST DEVICE FOR ELECTRICAL LINES

Abstract

The invention relates to a test device (1) for testing the insulation of an electrical line (2), in particular a cable or a cable harness, for detecting error points in the insulation of the electrical line (2). The test device (1) comprises a scalable, evacuable chamber (3) for completely accommodating the electrical line (2) to be tested, wherein at least one electrical connection point (6), preferably in the form of a plug device part, for connecting the electrical line (2) to be tested is arranged inside the chamber (3) and an electrical feedthrough (7) leads from the connection point (6) out of the chamber (3).

Claims

1-25. (canceled)

26. A test device (1) for testing the insulation of an electrical line (2), the test device (1) comprising a chamber (3) for completely accommodating an electrical line (2) to be tested, wherein the chamber (3) is sealingly closable and evacuable, so that a negative pressure, can be created inside the chamber (3), and wherein at least one electrical connection point (6) for connecting the electrical line (2) to be tested is arranged inside the chamber (3), and an electrical feedthrough (7) leads from the at least one electrical connection point (6) out of the chamber (3).

27. The test device according to claim 26, comprising a vacuum pump (10) connected to the chamber (3), the vacuum pump configured to evacuate the chamber (3).

28. The test device according to claim 26, wherein the chamber (3) defines one or more electrical feedthroughs (7) from the at least one electrical connection point (6) to the outside, each of the one or more electrical feedthroughs configured to form a seal with the chamber (3).

29. The test device of claim 26, wherein at least a portion of the housing of the chamber (3) is formed from conductive material that is connected to a ground.

30. The test device according to claim 26, wherein the at least one electrical connection point includes at least two electrical connection points (6), each configured as a connector arranged inside the chamber (3), wherein an electrical feedthrough (7) leads from the at least two connection points (6) out of the chamber (3); and/or wherein the at least one electrical connection point includes at least two electrical connection points (6) each configured as a connector and anchored at a common support element (9) in the form of a strip or plate, which can be removed from the housing of the chamber (3).

31. The test device according to claim 26, wherein the at least one electrical connection point (6) is anchored in or at an inner wall of the chamber (3).

32. The test device according to claim 26, wherein the at least one electrical connection point (6) is connected to a voltage source (8) arranged outside the chamber (3) via an electrical feedthrough (7).

33. The test device according to claim 26, wherein the chamber (3) is formed by a trough-like part (4) and a cover (5) covering the trough-like part (4), wherein a seal (14) is provided between trough-like part (4) and cover (5), which seal lies between cover (5) and trough-like part (4) in the closed state of the chamber.

34. The test device according to claim 33, wherein the at least one electrical connection point (6) is arranged in a side wall (4a) of the trough-like part (4), wherein the side wall (4a) defines an obtuse angle (a) with the base (4b) of the trough-like part (4) inside the chamber (3), wherein the obtuse angle (a) is between 100° and 150°.

35. The test device according to claim 33, wherein the test device (1) has a displaceable frame (13) supporting the chamber (3), wherein the chamber (3) and the frame (13) form a table.

36. The test device according to claim 35, wherein at least the trough-like part (4) of the chamber (3) forms an insert, which can be removed from the frame (13).

37. The test device according to claim 35, wherein the frame (13) supports at least one voltage source (8) connected to the at least one electrical connection point (6) and/or a vacuum pump (10) connected to the chamber (3) and/or a control means (11) for controlling the test device (1) and/or a user interface (12) for operating the test device (1).

38. The test device according to claim 33, wherein the cover (5), has at least one viewing window (15) or at least one transparent section.

39. The test device according to claim 33, wherein the cover (5) is formed by means of a plate, which is preferably horizontally displaceable and which forms a tabletop of the test device (1).

40. The test device according to claim 33, wherein the cover (5) can be displaced horizontally between closed and open position, and wherein the cover is guided by means of a guide (18) mounted on roller bearings.

41. The test device according to claim 26, comprising a seal (16) for sealing the inside of the chamber (3) with respect to the region outside the chamber (3), the seal arranged in a region between the at least one electrical connection point (6) and a wall of the chamber (3).

42. The test device according to claim 26, wherein the at least one electrical connection point (6) has a seal (17) arranged to seal the inside of the chamber (3) with respect to a space formed between the electrical connection point (6) and a connector part (20) of the electrical line (2) to be tested when the electrical conductor (2) is connected.

43. The test device according to claim 26, comprising at least one sensor device (21) configured for detecting and/or localizing a breakdown through the insulation of the electrical line (2) to be tested and/or configured for monitoring an electrical voltage applied to the electrical line (2) to be tested, wherein the sensor device (21) comprises an electrical measuring means (22) connected to an electrical connection point (6) or an optical detection means (23) arranged inside the chamber (3).

44. The test device according to claim 26, wherein the at least one electrical connection point (6) has a snap mechanism, for fixing a connector part (20) of the electrical line (2) to be tested at the at least one connection point (6).

45. The test device according to claim 26, comprising a spacer (19) of electrically insulating material in the form of a grid or mesh or in the form of strips, the spacer configured for spacing apart an electrical line (2) to be tested from the base (4b) of the chamber (3) and arranged on the base (4b) of the chamber (3).

46. A test method for detecting error points in the insulation of an electrical line (2), by means of a test device (1) according to 26, the method comprising: introducing at least one electrical line (2) to be tested into the chamber (3); connecting the electrical line (2) to at least one electrical connection point (6) of the chamber (3); evacuating the chamber (3) until a pressure of less than 500 mbar is reached in the chamber (3); and applying an electrical voltage between the electrical line (2) to be tested and an electrode (24) arranged inside the chamber (3), and/or between the at least one electrical lines (2) to be tested.

47. The test method according to claim 46, wherein the electrical line (1) to be tested is located in its entirety inside the chamber (3) during the test procedure.

48. The test method according to claim 46, further comprising determining a breakdown strength of the insulation of the at least electrical line to be tested.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0059] FIG. 1 shows an embodiment of a test device according to the invention,

[0060] FIG. 2 shows the outside of a side wall of the chamber,

[0061] FIG. 3 shows an electrical connection point with connected electrical line in detail,

[0062] FIG. 4 shows the evacuable chamber in detail,

[0063] FIG. 5 shows the rear side of the test device with voltage source and vacuum pump, and

[0064] FIG. 6 shows an embodiment of the invention.

DETAILED DESCRIPTION

[0065] FIG. 1 shows a test device 1 for testing the insulation of an electrical line 2, in particular of a cable or of a cable harness. In particular error points in the insulation of the electrical line 2 are detected thereby.

[0066] The test device 1 has a tightly closable, evacuable chamber 3 for completely accommodating the electrical line 2 to be tested. Several electrical connection points 6—here in the form of connector parts, such as connection plugs or connection sockets—for connecting the electrical line 2 to be tested are arranged inside the chamber 3. An electrical feedthrough 7 in each case leads from the connection points 6 out of the chamber 3 (FIGS. 2, 3, and 4), in order to connect the connection point 6 to a voltage source 8, which can be part of a measuring means.

[0067] In the closed state of the chamber 3, the inside of the chamber 3 is closed in a vacuum-tight manner to the outside and/or can be evacuated.

[0068] When applying a high voltage (after evacuation of the chamber), a voltage flashover to an electrode, which becomes visible as electric arc escaping from the cable, occurs in the region of the defect. The electrode is held at constant potential (e.g. ground). It is preferred when the housing or a housing part of the chamber 3 forms this electrode.

[0069] In the illustrated embodiment, at least a portion, preferably at least half or at least the base, of the housing of the chamber 3 is thus formed from conductive material, in particular metal, which is connected to a voltage source 8 and/or a potential, preferably ground (FIG. 4).

[0070] It would generally be possible to also provide only one connection point 6, but two or more are preferred, in order to be able to connect the lines to be tested on both ends or several lines simultaneously or complex cable harnesses to several connections. The individual connection points 6 can also have a different form.

[0071] In the embodiment of FIG. 2, the electrical connection points 6 are anchored at a common support element 9, preferably in the form of a strip or plate, which can be removed from the housing of the chamber 3.

[0072] As can be seen from FIG. 1 and FIG. 4, the electrical connection point(s) 6 is/are anchored in or on an inner wall of the chamber 3.

[0073] It can be seen from FIG. 5 that the electrical connection point 6 is connected to a voltage source 8 arranged outside the chamber 3 via the electrical feedthrough 7. A vacuum pump 10 for evacuating the chamber 3 is also connected to the chamber 3.

[0074] The chamber 3 in FIG. 1 and FIG. 4 is formed by a trough-like part 4 and a cover 5 covering the trough-like part 4. A seal 14 can be provided between the trough-like part 4 and the cover 5, which seal lies between cover 5 and trough-like part 4 in the closed state of the chamber (FIG. 4).

[0075] It can further be seen from FIG. 4 that the electrical connection points 6 are arranged in a side wall 4a of the trough-like part 4. This side wall 4a draws an obtuse angle α with the base 4b of the trough-like part 4 inside the chamber 3. The obtuse angle α is preferably between 100° and 150° e.g. essentially 120°.

[0076] The test device 1—according to the preferred embodiment—has a—preferably displaceable (see rollers in FIGS. 1 and 5)—frame 13 supporting the chamber 3. The chamber 3 and the frame 13 can thereby form a table. At least the trough-like part 4 of the chamber 3 can be formed as an insert, which can be removed from the frame 13 (FIG. 4).

[0077] The frame 13 can support at least one voltage source 8 connected to the at least one electrical connection point 6 and/or a vacuum pump 10 connected to the chamber 3 and/or a control means 11 for controlling the test device 1 and/or a user interface 12 (e.g. a screen and/or a keyboard and/or touchscreen) for operating the test device 1.

[0078] It can be seen from FIG. 1 that the chamber 3—here: in its cover 5—can have at least one viewing window 15 or at least one transparent section.

[0079] The cover 5 of the chamber 3 is formed by means of a plate, which is preferably horizontally displaceable, and which forms a tabletop of the test device 1. The cover 5 can thus be capable of being displaced between closed and open position, preferably in a horizontal direction. In the embodiment of FIG. 1, the cover is guided by means of a guide 18, which is preferably mounted on roller bearings. In FIG. 1, this guide 18 is in each case arranged in the edge region of the table.

[0080] FIG. 3 shows a possible connection situation of a connection point 6 (here of a connection socket) and a connector part 20 of a line 2 to be tested. It can be seen that a seal 16 for sealing the inside of the chamber 3 with respect to the region outside the chamber 3 is arranged in a region between the electrical connection point 6 and a wall of the chamber 3.

[0081] The at least one electrical connection point 6 additionally has a seal 17 facing the inside of the chamber 3 or—when the line 2 is connected—the connector part 20, respectively, in order to seal the inside of the chamber 3 with respect to a space formed between the electrical connection point 6 and the connector part 20 when the electrical conductor 2 is connected.

[0082] The at least one electrical connection point 6 can also have a fixing mechanism, preferably a snap mechanism, for fixing a connector part 20 of the electrical line 2 to be tested at the connection point 6.

[0083] FIG. 4 shows a further preferred feature, namely a spacer 19 of electrically insulating material, preferably in the form of a grid or mesh or in the form of strips, arranged on the base 4b of the chamber for spacing apart an electrical line 2 to be tested from the base 4b of the chamber 3, which base 4b also forms the (counter) electrode here.

[0084] FIG. 6 shows a further embodiment of the invention comprising sensor devices 21 for detecting and/or localizing a breakdown through the insulation of the electrical line 2 to be tested and/or for monitoring or controlling, respectively, the applied electrical (test) voltage. An electrical measuring means 22 (e.g. an amperemeter and/or voltmeter) can be provided as sensor device outside the chamber 3 and/or an optical detection device 23 (e.g. a camera) can be provided inside the chamber 3.

[0085] As can be seen from FIG. 6, at least two electrical connection points 6 can be present inside the chamber 3, wherein one of the connection points 6 is connected to a voltage source 8 (arranged outside the chamber 3), and another connection point 6 is connected to the measuring means 22 (arranged outside the chamber 3). An electrical line 2 to be tested is connected with one of its ends to the voltage source 8 via the one connection point 6, and with another end to the measuring means 22 via the other connection point 6. It goes without saying that the measuring means 22, the voltage source 8, and optionally also the control means 11 can be integrated into a common structural unit.

[0086] The electrode 24 is illustrated separately in FIG. 6. As already mentioned several times, the housing of the chamber 3 itself can also form the counter electrode.

[0087] The sensor means 21—as well as the voltage source 8—are connected to the control means 11 and are controlled by the latter.

[0088] Finally, the invention also relates to a test method for testing the insulation of an electrical line 2, in particular of a cable or of a cable harness, preferably for detecting error points in the insulation of the electrical line 2, by means of a test device according to the invention. The method comprises the steps of: [0089] a. introducing at least one electrical line 2 to be tested into the chamber 3 and connecting the electrical line 2 to at least one electrical connection point 6 of the chamber 3, [0090] b. evacuating the chamber 3 by means of a vacuum pump 10, preferably until a pressure of less than 500 mbar, preferably of less than 200 mbar, particularly preferably of less than 100 mbar, is reached in the chamber 3, [0091] c. applying an electrical voltage between the electrical line 2 to be tested and an inside of the chamber 3 and/or between electrical lines 2 to be tested.

[0092] While the electrical voltage is applied, it is monitored by means of the sensor means 21, which is connected—directly or indirectly—to the electrical line 2 to be tested and/or to the electrode 24, whether a breakdown occurs or to what extent the electrical voltage drops, respectively. The sensor means 21 can comprise, e.g., an amperemeter, a voltmeter, an electrical field meter and/or an optical detection means (such as, e.g., a camera) for detecting an electric arc escaping from the insulation.

[0093] A preferred embodiment is characterized in that the step of applying the electrical voltage and the step of monitoring the electrical line 2 are performed when the chamber 3 is evacuated (i.e. when negative pressure or vacuum, respectively, prevails in the chamber 3), preferably at a pressure in the chamber 3 of less than 50) mbar, preferably of less than 200 mbar, particularly preferably of less than 100 mbar.

[0094] The invention is not limited to the described and illustrated embodiments. It goes without saying that further designs are possible within the idea of the invention. Alternatives can in particular also refer to the constructive and functional design of the test device, preferably with regard to the user-friendliness and efficient and time-saving tests as well as the test procedure itself as well as the equipment and/or controls required for this purpose.

LIST OF REFERENCE NUMERALS

[0095] 1 test device [0096] 2 electrical line to be tested [0097] 3 chamber [0098] 4 trough-like part [0099] 4a side wall of the trough-like part 4 [0100] 4b base of the trough-like part 4 [0101] 5 cover [0102] 6 electrical connection point [0103] 7 electrical feedthrough [0104] 8 voltage source [0105] 9 support element [0106] 10 vacuum pump [0107] 11 control means [0108] 12 user interface [0109] 13 frame [0110] 14 seal [0111] 15 viewing window [0112] 16 seal [0113] 17 seal [0114] 18 guide [0115] 19 spacer [0116] 20 connector part of the electrical line 2 [0117] 21 sensor device [0118] 22 electrical measuring means [0119] 23 optical detection means [0120] 24 electrode