JP2010164407A - Temperature detection tool for twisted electric wires, and method for detecting temperature by using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detection tool that is attached to twisted electric wires and adapted to detect the hazard of breakage of a wire of the twisted electric wires by detecting abnormal heat, and to provide an efficient method for detecting the temperature of twisted electric wires by using the detection tool. <P>SOLUTION: A plurality of rectangular shaped coloring temperature indication pieces 11 for irreversibly indicating excess in a preset temperature of a wax meltable, at a specific temperature are arranged in a line on a rectangular shaped sheet-like substrate 1 at a front face side with intervals therebetween in a longitudinal direction. The distance between both ends of a group of the coloring temperature indication pieces in the longitudinal direction is equal to or longer than a length, whereby the coloring temperature indication pieces 11 contact all of the wires forming the outermost layer of the twisted electric wires 8-1 to 8-19, at least at one or more points in a single-twist pitch of the twisted electric wires. A window-like notch for discharging water is formed at a portion between the adjacent coloring temperature indication pieces. The top faces of the coloring temperature indicating pieces are covered with a transparent film. An adhesive material layer is formed on the substrate at the rear-surface side so that the coloring temperature indicating pieces can be stuck to the twisted electric wires at the lower face side, in such a manner that the longitudinal directions of the coloring temperature indication pieces coincide. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a temperature detector for twisted wires, and a temperature detection method using the same, and more specifically, affixed to the twisted wires and detecting abnormal heat generation from the twisted wires, thereby breaking the strands of the twisted wires. The present invention relates to a detector for detecting danger and an efficient method for detecting the temperature of a twisted electric wire using the detector.

  A twisted electric wire obtained by twisting a plurality of strands is widely used in various electric facilities including electric railway facilities. Many twisted wires are used in harsh environments with vibration, corrosion, temperature changes, etc., and the wires are always cut due to various causes such as corrosion and damage due to aging and mechanical stress from the outside. You are in danger. If some of the strands that make up a twisted wire cause abnormal heat generation due to some cause, it often leads to disconnection, in which case the current distribution in the twisted wire becomes unbalanced, Some strands become overcurrent, and the breaks in the strands gradually increase, eventually leading to major obstacles. In addition, it is said that a large amount of current flows through the outermost strand in a twisted electric wire in which a plurality of strands are twisted together, and abnormal heat generation related to the breakage of the strand also occurs a lot in this outermost strand. is doing.

  In particular, in electric railway facilities, twisted wires are used in many places, and among them, feeders that supply electricity to trolley wires are particularly important. Because it flows continuously over time, early detection of strand breaks in twisted wires used as feeders is extremely important for ensuring safe railway operation. In this feeder, a compression connecting pipe (sleeve) is often used for electrical connection between the feeders or other members. When connecting with a compression connecting pipe, a wire is placed near the compression connecting pipe. There are relatively many cuts, and conventionally, the vicinity of the compression connecting pipe has been intensively inspected.

JP-A-6-294776

None

  Abnormal heat generation of strands is a sign of wire breakage and is often caused by wire breakage, and there is a correlation between strand breakage and abnormal heat generation of twisted wires constituting feeders. It has hitherto been known that if an abnormal heat generation of a combined electric wire can be detected by some means, it is possible to detect a broken wire or a sign of the twisted electric wire.

  For this reason, several attempts have been made to discover abnormal heat generation in twisted wires such as conventional wires. One of the attempts is detection of abnormal heat generation by a color-forming type temperature indicator. Colored type temperature indicator is a label-like or sheet-like temperature indicator that irreversibly displays the fact that the set temperature is exceeded by color development using the melting action of heat such as wax, and this is a compression connection of twisted wires It is wrapped around a place where abnormal heat generation is likely to occur, such as in the vicinity of a tube, and the abnormal heat generation is detected by color development.

  However, twisted wires such as feeders are generally installed at relatively high positions, such as 4.0 to 8.0 m above the ground, and when this colored indicator piece is wrapped around the twisted wires, Even if it can be seen from below, the upper surface portion cannot be seen from below, so there is a problem that a complete inspection is impossible unless a ladder is used and the top is looked down from above. In particular, in the feeders, the temperature detection points are very large, and when using a ladder, etc., the color-coded type temperature-indicating piece is excellent because it can easily know the fact that the set temperature has been exceeded by color development. The characteristic was ruined and was not satisfactory at all.

  In addition, since a twisted electric wire is made of a plurality of strands twisted together, if a colored color indicating piece is attached only to the lower surface portion, if the upper strand breaks, the heat from the strand breaks Only when it is transmitted to the part, the colored color indicator can detect abnormal heat generation, the detection accuracy is remarkably lowered, and even though the wire breakage has occurred, the colored indicator temperature piece may not develop color. There was a serious problem in gender. Accordingly, it has been unavoidable that the detection of abnormal heat generation by pasting a conventional colored color indicating temperature piece has not yet reached the practical range.

  On the other hand, an attempt has been made to detect the breakage of the strands by imaging the heat generation state of the twisted wires such as feeders using an infrared camera. An infrared camera captures the intensity of infrared radiation from an object and presents it as an image. If there is heat that is a sign of wire breakage or twisted wire such as feeders, Because of the temperature difference, an image of a specific color will be displayed, so if you look at it, you can know the wire breakage or its sign in a non-contact manner from a position away from it, and you should be able to detect it very efficiently .

  However, in the case of an infrared camera, if the emissivity of the object to be detected, that is, the subject, is not constant, accurate detection cannot be performed, and reflections from structures in the vicinity of the subject are also detected. There was a serious drawback. In particular, twisted wires such as feeders and compression connecting pipes have various emissivities due to differences in material, shape, age, and environment. It was difficult in practice to accurately detect abnormal heat generation. However, it is also true that some of the advantages of infrared cameras that can perform detection work efficiently without contact are difficult to throw away.

  As a result of earnest research to obtain a detection tool and a detection method capable of highly accurately and efficiently detecting abnormal heat generation related to breakage of strands of twisted wires such as feeders, the present inventors have achieved a new The present inventors have succeeded in developing a temperature detector for twisted wires and a temperature detection method using the same, and propose the present invention here.

  A color-development temperature indicating body that irreversibly displays the fact that the set temperature is exceeded using the action of a wax that melts at a specific temperature set in advance is the surface side of a rectangular sheet-like substrate. The distance between both ends of the color-development-type temperature indicating body is the entire outer layer of the twisted electric wire within one twist pitch of the twisted electric wire that is a temperature detection target. The above-mentioned problems have been solved by a temperature detector for twisted electric wires, which has a length that is long enough to allow the wire and the colored thermostat to be in contact with each other in at least one place. In addition, this temperature detector for twisted wires is affixed in advance to the desired position of the twisted wire that is the object to be detected, the affixed portion is photographed with an infrared camera, and abnormal heat generation is detected from the obtained image. If both are used together, abnormal heat generation can be detected more efficiently and with high accuracy.

  The wire is attached to the lower surface of the twisted wire for use. Even if the twisted wire is at a high position, the colored thermostat is visually observed while looking up from below to detect abnormal heat generation of the twisted wire. I can do it. In other words, it is considered that some part of the colored thermostat is in contact with the strands constituting all outermost layers within one twist pitch, so even if the strands in the upper part cannot be seen directly from below. Even if an abnormal heat generation occurs, the heat generation is transmitted downward through the strands that are repeated up and down so as to wave at every twisting pitch. The body will react. Therefore, even if this twisted electric wire is arranged at a high place, the fact of abnormal heat generation can be known from below. In addition, when the color-development type temperature indicator is composed of a plurality of the same type of temperature indicating pieces, and a window-shaped cutout for draining is formed between them, rainwater is attached to the twisted wire to which the temperature detector for the twisted wire is attached. Even if water such as water enters, the water is quickly discharged from the cutout, and moisture is stagnated inside, thereby preventing abnormal heat generation or corrosion of the strands. In addition, ventilation and ventilation of the pasted part are also achieved, and almost the same environment as the part not pasted is maintained. Furthermore, since the surface of the colored thermostat is covered with a transparent film, the emissivity of infrared rays is kept constant by this transparent film, and the surface of the colored display is changed depending on the material, shape, aging, etc. Therefore, it is possible to detect the breakage of the strands with higher accuracy than before by the image analysis of the infrared camera. Therefore, a primary inspection is performed speedily without contact with an infrared camera, and the suspicious part of this primary inspection is actually observed for the presence or absence of irreversible coloring on the twisted wire temperature detector. The detection method of finally determining the fact of the broken wire becomes possible. In addition, carry out a primary inspection with this temperature detector for twisted wires, and then make a final determination with an infrared camera.

The top view of Example 1 of the temperature detection tool for twisted electric wires which concerns on this invention. Similarly, the perspective view of the state with which the twisted electric wire which is a detection object was mounted | worn. Similarly, the partial expansion perspective view. Similarly, in order to show the relationship between the temperature detector for twisted wires and the twisted wires, a development explanatory view in which the twisted wires are cut open and developed in the vertical direction. Similarly, development explanatory drawing at the time of changing the magnitude | size of the color development type | mold temperature indicator 11. FIG. Similarly, development explanatory drawing at the time of changing the magnitude | size of the color development type | mold temperature indicator 11. FIG. Similarly, the expansion explanatory drawing of the comparative example which showed the case where the magnitude | size of the temperature indicator 11 is inadequate. The top view of Example 2 of the temperature detection tool for twisted electric wires which concerns on this invention. Similarly, the perspective view of the state with which the twisted electric wire which is a detection object was mounted | worn. Similarly, the partial expansion perspective view. Similarly, in order to show the relationship between the temperature detector for twisted wires and the twisted wires, a development explanatory view in which the twisted wires are cut open and developed in the vertical direction. Similarly, the expansion explanatory drawing at the time of changing the magnitude | size of each temperature piece 2 which comprises the color development type | mold temperature indicator 11. FIG. Similarly, the expansion explanatory drawing at the time of changing the magnitude | size of each temperature piece 2 which comprises the color development type | mold temperature indicator 11. FIG. Similarly, the development explanatory drawing of the comparative example which showed the case where the magnitude | size of each temperature-indicating piece 2 which comprises the color development type | mold temperature indicator 11 is unsuitable. Explanatory drawing of Example 3 of this invention. But of course it is possible.

  The surface of the base material in the form of a rectangular sheet is a rectangular colored display body that irreversibly displays the fact that the preset temperature has been exceeded by using the action of wax that dissolves at a preset temperature. All the strands that constitute the outermost layer of the stranded wire within the one twist pitch of the stranded wire that is a temperature detection object. And the color-forming shape indicating body are set to a length that is sufficient to allow contact with at least one place.

  FIG. 1 is a perspective view of a temperature detecting device for a twisted wire according to a first embodiment of the present invention, FIG. 2 is a side view of the twisted wire that is a detection target, and FIG. 3 is a partially enlarged view of the same. A perspective view and FIG. 4 are developed explanatory views in which the twisted electric wire is cut open and developed in order to show the relationship between the twisted electric wire temperature detector and the twisted electric wire.

  In the figure, reference numeral 1 denotes a rectangular sheet-like substrate, and an adhesive layer 9 is formed on the back side thereof. Reference numeral 11 denotes a color-forming temperature indicating body that irreversibly displays the fact that the temperature exceeds the set temperature by using the action of the dissolving petroleum wax when the temperature exceeds a preset specific temperature, and has a rectangular shape. . In addition, this color development type | mold temperature indicator 11 used what was proposed as Unexamined-Japanese-Patent No. 2006-29945.

  And this coloring form temperature indicator 11 is arrange | positioned toward the longitudinal direction of the base material 1, and the transparent film 4 has coat | covered it on it. As a material of the transparent film 4, polyethylene terephthalate resin is preferable from the viewpoint of emissivity, weather resistance, and the like. The distance X between the longitudinal ends of the color-forming temperature indicating bodies 11 is the color-coded temperature indicating all the strands 8 constituting the outermost layer within one twist pitch of the stranded wire 5 that is the object of temperature detection. The length of the body 11 is more than enough to be able to contact at least one place. In addition, the twist pitch means the space | interval until the strand 8 which comprises the outermost layer of the twisted electric wire 5 is twisted 360 degrees, and returns to the original position (angle), and is shown as P in FIG. ing. In FIG. 2, one of the strands 8 is displayed in black for the sake of convenience in order to make this twist pitch easy to understand.

  FIG. 4 shows the positional relationship between the colored color indicator 11 arranged on the substrate 1 and each of the strands 8 constituting the outermost layer of the twisted electric wire 5, so that the twisted electric wire 5 is cut open in the vertical direction. FIG. 5 is a development explanatory view showing only the strands 8 for one twist pitch, and the twisted electric wire 5 shown in FIG. 4 has a total of 19 strands of 8-1, 8-2,. Thus, the outermost layer is formed, and the color-developing temperature indicating body 11 is disposed on the substrate 1. And the assembly | assembly of this strand 8 ... for 1 twist pitch is repeated back and forth, and the elongate twisted electric wire 5 is comprised. In FIG. 4, W indicates the width of the color-forming shaped temperature indicator 11.

  In the twisted electric wire 5 shown in FIG. 4, the upper left part a of the color-developing temperature indicating body 11 is in contact with the element wire 8-1, and the lower right part b is in contact with the element wire 8-19. −1,..., 8-19 and the color-forming shaped temperature indicator 11 are always in contact with each other at one or more places.

  On the other hand, the color-forming temperature indicating piece 11 'shown in FIG. 5 has a width W' wider than that of the color-forming temperature indicating body 11 shown in FIG. Is smaller than that shown in FIG.

  On the contrary, since the color developing temperature indicating body 112 shown in FIG. 6 has a width W2 smaller than that of the color developing temperature indicating body 11 shown in FIG. 4, the distance X2 between both ends of the color forming temperature indicating body 112 is larger than that shown in FIG. Yes. As described above, the distance X between the both ends of the color-forming temperature indicating body 11 varies depending on the width W of the color-forming temperature indicating body 11 that comes into contact with the twisted electric wire 5.

  In the comparative example shown in FIG. 7, the left upper part a ′ of the color developing type temperature indicator 11 ′ ″ is not in contact with the element wire 8-1 and the lower right part b ′ is not in contact with the element wire 8-19. Therefore, the abnormal heat generation of the wires 8-1 and 8-19 cannot be detected, which is not preferable. 4 is a case where the distance X between both ends is minimized. If the distance X between both ends is further increased, all the strands 8-1,... -19 will come into contact with the colored thermostat 11 at more locations, but as X increases, the abnormal heat generation location of the strand 8 and the developed location of the colored thermostat 11 may become farther apart. This is not preferable because the detection sensitivity is lowered, and if the width W of the color-development-type temperature indicator 11 is made too large, a portion that cannot be seen well from below may be generated. Absent.

  This Example 1 has the configuration as described above, and compresses a stranded wire 5 used as a feeder wire as shown in FIG. 2 using an adhesive layer 9 formed on the back surface of the substrate 1. Attached to the lower surface of a desired location, such as the vicinity of the location where the connecting pipe 7 is attached, is used. In addition, you may attach using a commercially available binding band etc., without using the adhesive material layer 9. FIG. In this state, if any of the strands 8 constituting the twisted electric wire 5 causes abnormal heat generation for some reason, the strand 8 is formed of the colored display temperature indicator 11 disposed within one twist pitch. Since it is always in contact with somewhere, the abnormal heat generation of the strand 8 reacts with the corresponding portion of the colored display body 11 and a coloring phenomenon occurs around the portion where the strand 8 is in contact.

  At this time, since the colored thermometer 11 is affixed to the lower surface of the twisted electric wire 5, even if the twisted electric wire 5 is at a high position, the colored thermostat 11 is visually observed while looking up from below. It is possible to detect abnormal heat generation of the stranded wire 5. In other words, in this embodiment, since it is considered that somewhere in the colored thermostat 11 is in contact with all the strands 8 constituting the outermost layer within one twist pitch, even from the lower side. Even if an abnormal heat generation occurs in the upper part of the wire 8 that cannot be directly seen, the heat is transmitted downward through the wire 8 that repeats up and down so that it undulates at every twist pitch. As a result, the colored thermostat 11 attached to the lower surface is allowed to react. Therefore, even if this twisted electric wire 5 is arranged at a high place, the fact of abnormal heat generation can be known from below.

  In this Example 2, as shown in FIG. 8, the color-development-type temperature indicator 11 is composed of a plurality of temperature-indicating pieces 2 having the same shape as a square, and the plurality of temperature-indicating pieces 2 are formed on the substrate 1. The substrate 1 is arranged in a row in the longitudinal direction of the substrate 1 with a space therebetween, and the transparent film 4 covers it. The distance X between the longitudinal ends of each of the temperature indicating pieces 2... Constituting the color forming temperature indicating body 11 is the entire outermost layer in one twist pitch of the twisted electric wire 5 that is the object of temperature detection. The strands 8 ... and the temperature-indicating piece 2 are at least as long as they can contact at least one place.

  FIG. 11 shows the relationship between each temperature indicating piece 2 constituting the colored color indicating temperature body 11 in Example 2 and each of the strands 8 constituting the outermost layer of the stranded wire 5. The wire 5 is cut in the vertical direction, and is a development explanatory view showing only the strands 8 for one twist pitch. The twisted wire 5 shown in FIG. , 8-2,..., 8-19, the outermost layer is formed by a total of 19 strands. On the other hand, the temperature-indicating pieces 2 constituting the colored-type temperature indicating body 11 are arranged on the substrate 1 at intervals. Yes. And the assembly | assembly of this strand 8 ... for 1 twist pitch is repeated back and forth, and the elongate twisted electric wire 5 is comprised. 4 indicates the width of the temperature indicating piece 2.

  In the stranded wire 5 shown in FIG. 11, the upper left portion a of the temperature indicating piece 2-1 constituting the color forming type temperature indicating body 11 is in contact with the element wire 8-1, and the color forming type temperature indicating body 11 is also connected. The lower right part b of the temperature indicating piece 2-5 is in contact with the wire 8-19, and the wires 8-1,... 8-19 and the colored color indicating body 11 are always in contact with one or more places. It will be.

  On the other hand, the temperature piece 2 'shown in FIG. 12 has a width W' wider than that of the colored color indicator 11 shown in FIG. 11, so that the distance X 'between both ends of the temperature pieces 2'. Smaller.

  On the other hand, the temperature piece 2 2 shown in FIG. 13 has a width W2 smaller than that of the colored color indicator 11 shown in FIG. 11, and therefore the distance X2 between both ends of the temperature pieces 2 2... Is larger than that shown in FIG. In this way, the distance X between the ends of the temperature indicating pieces 2... Constituting the color forming temperature indicating body 11 changes depending on the size of the width W of the temperature indicating piece 2 to be in contact with the twisted electric wire 5.

  In the comparative example shown in FIG. 14, the left upper portion a ′ of the temperature indicating piece 2 ′ ″-1 located at the left end is not in contact with the element wire 8-1, and the temperature indicating piece 2 ″ ″ located on the right side. Since the right lower part b ′ of -4 is not in contact with the wire 8-19, abnormal heat generation of the wires 8-1 and 8-19 cannot be detected, which is not preferable. The arrangement of the temperature-indicating pieces 2 shown in FIG. 11 is a case where the distance X between both ends is minimized. If the distance X between both ends is further increased, all the strands 8-1,. 19 is more in contact with the temperature-indicating pieces 2... However, as X increases, there is a possibility that the heat insulation portion of the wire 8 and the color-developing portion of the temperature-indicating piece 2 are far away from each other, and the detection sensitivity decreases. For this reason, it is not preferable, and if the width W of the temperature indicating piece 2 is too large, a portion that cannot be seen well from below may be generated, which is also not preferable.

  Further, in the second embodiment, a window-shaped cutout 6 for draining is formed between the adjacent temperature indicating pieces 2 and 2 and has a square shape penetrating the front and back of the substrate 1. This Example 2 has the configuration as described above, and uses the adhesive layer 9 formed on the back surface of the substrate 1 to compress the twisted wire 5 used as a feeder as shown in FIG. Attached to the lower surface of a desired location, such as the vicinity of the location where the connecting pipe 7 is attached, is used. In addition, you may attach using a commercially available binding band etc., without using the adhesive layer 9. FIG. In this state, if any of the wires 8... Constituting the twisted electric wire 5 causes abnormal heat generation for some reason, the wires 8 are arranged in a row within one twist pitch. Since it is always in contact with any of the wires 8, the abnormal heat generation of the wire 8 causes any one of the temperature indicating pieces 2 to react, and a coloring phenomenon occurs around the portion where the wire 8 is in contact.

  At this time, since the temperature indicating piece 2 constituting the color forming type temperature indicating body 11 is attached to the lower surface of the twisted electric wire 5, even if the twisted electric wire 5 is at a high position, the temperature indicating piece is looked up from below. It is possible to detect the abnormal heat generation of the twisted electric wire 5 by visually observing the piece 2. That is, in this Example 2, it is considered that some of the temperature indicating pieces 2 are in contact with all the strands 8 constituting the outermost layer within one twist pitch. Even if an abnormal heat generation occurs in the upper part of the wire 8 that cannot be directly seen, the heat is transmitted downward through the wire 8 that repeats up and down so that it undulates at every twist pitch. Therefore, the temperature indicating piece 2 attached to the lower surface is caused to react. Therefore, even if this twisted electric wire 5 is disposed at a high place, the fact of abnormal heat generation can be known from below.

  In Example 2, since the window-shaped cutout 6 for draining water is formed between the temperature indicating pieces 2 and 2, the twisted wire 5 to which the twisted wire temperature detector is attached. Even if water such as rainwater enters, water is quickly discharged from the cutout 6 to prevent moisture from accumulating and causing abnormal heat generation or corrosion of the strands. . In addition, ventilation and ventilation of the pasted portion are also achieved, and the same environment as the portion where the temperature detecting tool is not pasted is maintained.

  This Example 3 is a method for detecting the breakage of the strands of the stranded wire 5 with high efficiency and high accuracy by using the temperature detector for the stranded wire and the infrared camera shown in Example 1 or Example 2 together. Yes, as shown in FIG. 15, in Example 3, the temperature detection for the twisted wire according to Example 1 or Example 2 is provided on the lower surface of the desired position, such as the vicinity of the location where the compression connecting pipe 7 of the twisted wire 5 is attached. A tool is attached in advance, and when the twisted electric wire 5 is energized, the pasted portion is photographed by the infrared camera 10, and the possibility of abnormal heat generation is known from the obtained image. The color development status of the temperature detector for the matching wire is actually confirmed with the eyes, and the fact of the wire breakage is judged.

  In the case of the infrared camera 10, as described above, there is a drawback that accurate detection cannot be performed unless the detection object, that is, the emissivity of the subject is constant. However, in the inspection method shown in the third embodiment, A twisted wire temperature detector shown in Example 1 or Example 2 is affixed to a twisted wire 5, the surface of which is covered with a transparent film 4, and the emissivity is the material of the transparent film 4. Therefore, the emissivity from the surface does not vary depending on the material, shape, aging, etc. of the twisted electric wire 5 or the compression connecting pipe 7, and the emissivity is always kept almost constant. By the image analysis of the infrared camera 10, it is possible to detect abnormal heat generation related to the wire breakage with higher accuracy than before. Therefore, the primary inspection is performed speedily in a non-contact manner by the infrared camera 10, and the suspicious portion of the primary inspection is actually checked for the presence or absence of irreversible coloration of the attached twisted wire temperature detector. As a result, a two-stage method of finally determining the fact of abnormal heat generation becomes possible. Of course, it is possible to carry out a primary inspection with this temperature detector for twisted wires and then make a final determination using an infrared camera.

  As described above, in the twisted wire temperature detector and the temperature inspection method using the same according to the present invention, the abnormal heat generation related to the strand breakage of the twisted wire leading to a major accident is detected with high accuracy and high efficiency. It has an excellent effect that can contribute to accident prevention in various facilities using twisted wires such as electric railway facilities.

  It can be used in all electric facilities that use twisted wires, including electric railway facilities.

DESCRIPTION OF SYMBOLS 1 Base material 2 Indicating piece 3 Color development type 4 Transparent film 5 Twisted electric wire 6 Cutout 7 Compression connection pipe 8 Elementary wire 9 Adhesive material layer 10 Infrared camera 11 Color development type thermal indicator

Claims (6)

  A color-development temperature indicator that has a rectangular shape that irreversibly displays the fact that the preset temperature has been exceeded using the action of a wax that melts at a specific temperature set in advance, on the surface side of a rectangular sheet-like substrate The distance between both ends of the color-development-type temperature indicating body is the entire outer layer of the twisted electric wire within one twist pitch of the twisted electric wire that is a temperature detection target. A temperature detector for a twisted electric wire, characterized in that the wire has a length that is long enough to allow the colored wire and the color-developing temperature indicator to come into contact with each other at least at one location.   The temperature detection tool for twisted wires according to claim 1 is attached in advance to a desired position of the twisted wire that is a detection target, the attached portion is photographed with an infrared camera, and abnormal heat generation is detected from the obtained image. A temperature detection method for twisted electric wires, characterized in that.   The color-development-type temperature indicator is composed of a plurality of rectangular-shaped temperature-indicating pieces, which are arranged at intervals in the longitudinal direction on the surface side of the substrate. The temperature detector for twisted electric wires according to claim 1.   The temperature detector for twisted electric wires according to claim 3, wherein a window-shaped cutout for draining water is formed between adjacent temperature indicating pieces. An adhesive material layer is formed on the back surface side of the base material, and the adhesive material layer is used to be attached to the lower surface side of the twisted electric wire so that the respective longitudinal directions are matched. The temperature detector for twisted electric wires according to claim 1. The temperature detector for twisted wires according to claim 1, wherein a transparent film made of polyethylene terephthalate resin is used.

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