JPH0239353Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention relates to a device for detecting and displaying deterioration of lightning protection means such as lightning arresters installed for the purpose of protecting power distribution lines, power distribution equipment, etc. To explain in detail, it remains inoperable in response to shock discharge current caused by lightning, etc., but when the ground leakage current value of lightning arresters, etc. continuously reaches a predetermined level, this leakage current is detected. The present invention relates to a deterioration display device that immediately provides a simple display that can be clearly and reliably viewed by inspection.

Prior Art As power distribution networks become larger and more complex,
For the purpose of protecting lines and equipment from lightning surges, etc.
Alternatively, a huge number of lightning arresters are installed for insulation coordination. As the number of installed lightning arresters increases, the number of deteriorated lightning arresters also increases. After an excessive discharge current flows due to a lightning surge or the like, or when moisture infiltrates inside the arrester, the arrester deteriorates, and a considerable amount of leakage current to the ground occurs in the deteriorated arrester. If such a deteriorated lightning arrester is left unattended, it may lead to accidents such as ground faults, and the ground fault relays at substations may detect faults in response to this leakage current, leading to power outages.

Purpose From the above-mentioned viewpoints, this invention is designed to provide accurate and simple deterioration indications in response to only the continuously flowing earth leakage current that is connected in series between a lightning protection means such as a lightning arrester and the earth. The purpose of the present invention is to provide a deterioration display device that has the following characteristics. Another object of this invention is to provide a deterioration indicating device that is integrally constructed in a compact manner and is extremely easy to attach and detach from a lightning arrester.

Embodiment An embodiment embodying this invention will be described below with reference to FIGS. 1 to 4.

Reference numeral 1 denotes a lightning arrester connected in series with this deterioration display device, which is illustrated as a general lightning arresting means.
Reference numeral 2 denotes an insulating outer cylinder made of synthetic resin that can be seen from the outside of the deterioration display device, and numeral 3 denotes sealing plugs fixed to close both ends of the insulating outer cylinder 2. 4
Reference numerals a and 4b denote first and second opposing electrodes inserted along the axial direction of the insulating outer cylinder 2 through both sealing plugs 3.

The first counter electrode 4a protrudes outward from the axis and is separably arranged with respect to the insulating outer cylinder 2, and has a synthetic resin whose central part in the radial direction is inserted into and locked at both ends of the sealing plug 3. A locking pin Pa made of the same material is passed through the bolt, and its outer end is connected to the lightning arrester 1. The diameter of the pin Pa may be appropriately reduced so that it is easily broken at the boundary between the first counter electrode 4a and the sealing plug 3. During normal handling, the first counter electrode 4a is locked to the sealing plug 3 by the pin Pa, so that it does not come off from the insulating outer cylinder 2. The second counter electrode 4b is fixed to the sealing plug 3 by having both ends of the second counter electrode 4b penetrate the sealing plug 3 in the radial direction thereof with a metal retaining pin Pb which is inserted into the sealing plug 3 and locked therein. A grounding wire (not shown) is connected to the outer end.

5 has both ends of the first and second opposing electrodes 4a,
A heating resistor connected to the inner end of 4b,
The connecting portions 5a and 5b are attached so that when the first opposing electrode 4a receives a force outward from the axis, one of the connecting portions 5a and 5b is separated. In addition to ordinary electrical resistance such as this heating resistor, a PTC (positive polarity thermistor), which has a significant temperature dependence, is also used.

Reference numeral 6 denotes an incendiary agent placed around the resistor 5 by means of painting or the like, which presses the first opposing electrode 4a due to the pressure increase during ignition and breaks the retaining pin Pa. The lock is released, and the first opposing electrode 4a is moved outward from the axis to separate it from the insulating outer cylinder 2. Further, the ignition agent 6 is selected to have a property that, when ignited, it exhibits a color different from the outer surface of the cylindrical electrode described later, for example, black. Furthermore, the ignition temperature of the ignition agent 6 and the heat generation characteristics of the resistor 5 are selected such that ignition occurs when a continuous current of a certain level (for example, about 100 mA), that is, alternating current or direct current, flows through the resistor 5. It is.

Reference numeral 7 denotes a cylindrical electrode whose one end is caulked to the inner end of the second opposing electrode 4b on the grounding side at a part of the outer periphery as shown in FIG. 3, and the other end is on the resistor 5 and the lightning protection means side. It extends so as to cover the inner end of the first counter electrode 4a. The outer surface of the cylindrical electrode 7 is colored in a color indicating the normal state of the lightning arrester 1, for example, yellow, or a yellow tube is inserted therein. 8 is a cylindrical electrode 7
and the second counter electrode 4b on the ground side, so that when the ignition agent 6 is ignited, a jet flow due to the pressure increase can be ejected to the outside through the gap 8. It's getting old.

Reference numeral 9 denotes an insulating spacer fitted over the inner end of the first opposing electrode 4a on the side of the lightning arrester, and is formed into a cylindrical shape, and the other end of the cylindrical electrode 7 is attached to the outer periphery of the insulating spacer. It is fitted. Reference numeral 11 denotes a discharge gap provided between the first opposing electrode 4a on the side of the lightning protection means and the cylindrical electrode 7. Reference numeral 13 denotes a pair of covers fitted to both ends of the insulating outer cylinder 2, which are bonded to the outer ends of the insulating outer cylinder 2. Note that the insertion hole 13a of the cover 13 through which the first counter electrode 4a is inserted is the first counter electrode 4a.
It is formed to have a slight distance from the outer periphery of the first opposing electrode 4a so as to be movable outward from the axis.
In addition, the portions where the first and second counter electrodes 4a, 4b and the cover 13 are inserted are sealed with a sealant for waterproofing (for example, "Silicon Sealant" manufactured by Shin-Etsu Chemical Co., Ltd. under the trade name "Silicone Sealant"). There is.

Now, the operation of the deterioration display device having the above configuration will be explained.

When the lightning arrester 1 has not deteriorated and its ground leakage current is below a predetermined level, the cylindrical electrode 7 turns yellow through the insulating outer cylinder 2, indicating the normal state of the lightning arrester 1.

When a shock wave due to lightning or the like enters the lightning arrester 1 in this state, the terminal voltage of the discharge gap 11 rises rapidly, a flashover occurs in the discharge gap 11, and the discharge current flows to the ground via the arrester 1 and the discharge gap 11. At this time,
Since the resistor 5 and the pyrotechnic agent 6 are configured to act thermally as described above, the pyrotechnic agent 6 remains unignited for a short period of time until it sparks in the discharge gap 11. Further, since the terminal voltage of the resistor 5 is kept low after the ignition, the ignition agent 6 similarly remains unignited. In this manner, when the lightning arrester 1 does not deteriorate, the deterioration display device having the above structure continues to display the normal state of the lightning arrester 1, whether the lightning arrester 1 is in operation or not.

Then, when the continuous leakage current to the ground of the arrester 1 reaches a predetermined level due to several discharges of the arrester 1 or due to deterioration over time, the ignition agent 6 is ignited by the Joule heat generated in the resistor 5. The sudden pressure increase due to the ignition of the pyrotechnic agent 6 presses the first opposing electrode 4a, which breaks the retaining pin Pa and releases the lock from the sealing plug 3. First counter electrode 4
a is moved to protrude and separate, and the separated state can be visually recognized from the outside. Furthermore, when the pyrotechnic agent 6 is ignited, the pressure inside the cylindrical electrode 7 increases, and a black jet flows through the gap 8 into the insulating outer cylinder 2, causing fine combustion products to flow into the inner surface of the insulating outer cylinder 2. and adheres to the outer surface of the cylindrical electrode 7. As a result, the external appearance of the insulating outer cylinder 2 appears black, indicating the deterioration state of the lightning arrester 1.

In this way, the display device has a state in which the first counter electrode 4a is separated from the insulating outer cylinder 2 and a state in which the first counter electrode 4a is separated from the insulating outer cylinder 2.
Surge arrester 1 is indicated by a double display with a black appearance.
Deterioration can be confirmed, and the visual effect is high.

Note that if PTC is used as the resistor 5, the resistance value of the display device when displaying a normal state can be kept low.

Effects As detailed above, this invention includes an outer cylinder whose inside can be seen through, a first counter electrode that is separably inserted and attached to one end of the outer cylinder, and a second electrode that is attached to the other end of the outer cylinder. a second counter electrode that is inserted through and fixed to the first counter electrode and is arranged opposite to the first counter electrode; and a second counter electrode that is separably attached to one of the two counter electrodes, and A resistor is connected and fixed to the counter electrode, and one end is fitted onto the first counter electrode via an insulating spacer so as to have a discharge gap between the first counter electrode and the first counter electrode. , the other end is connected to and fixed to a second opposing electrode with a gap in a part of the circumferential direction of the second opposing electrode; When a predetermined level of continuous leakage current flows through the body, the resistor generates heat and ignites, causing a jet flow to eject into the outer cylinder, discoloring the inside of the outer cylinder, and separating the first counter electrode from the outer cylinder. By being composed of an actuating pyrotechnic agent, it responds only to the continuously flowing ground leakage current, and has a high accuracy and visibility effect.
It can be manufactured with a simple configuration, and it can also be attached to and detached from the lightning arrester extremely easily.

Furthermore, the present invention provides a double display of deterioration, showing the state in which the first counter electrode is separated and the state in which the inside of the outer cylinder is discolored by the ejected gas, so that the visual recognition effect is high.

Furthermore, in the case of a type in which a member that also serves as a display is separated from the display device, there is a risk that the member may separate if external force is applied to the deteriorated display device for some reason.
Even in such a case, the present invention can easily distinguish that even if the first counter electrode is separated from the outer cylinder, if the inside of the outer cylinder is not discolored, this is not an indication of deterioration of the lightning arrester. From this point of view, the present invention has the effect of being able to reliably display deterioration.

[Brief explanation of drawings]

Fig. 1 is a basic circuit configuration diagram of the deterioration display device of the present invention, Fig. 2 is a longitudinal sectional view of the deterioration display device, Fig. 3 is a sectional view of the main part showing the caulking of the cylindrical electrode, and Fig. 4 is FIG. 3 is a sectional view of a main part showing an operating state after displaying deterioration. Lightning arrester...1, Insulating outer cylinder...2, First counter electrode...4a, Second counter electrode...4b, Resistor...
...5. Ignition agent...6. Cylindrical electrode...7. Between...
8. Insulating spacer...9. Discharge gap...11. Retaining pin...Pa.

Claims (1)

[Claims for Utility Model Registration] An outer cylinder 2 whose interior can be seen through; a first opposing electrode 4a that is separably inserted and attached to one end of the outer cylinder 2; and the other end of the outer cylinder 2. A second counter electrode 4b is inserted through and fixed to the first counter electrode 4a and is disposed opposite to the first counter electrode 4a, and one of the counter electrodes 4a and 4b is separable. A resistor 5 is attached and connected and fixed to the other opposing electrode 4b, and one end side has a discharge gap 11 between the first opposing electrode 4a and the first opposing electrode 4a. is externally fitted through an insulating spacer 9, and the other end is connected and fixed to the second opposing electrode 4b with a gap 11 in a part of the circumferential direction of the second opposing electrode 4b. It is arranged around the cylindrical electrode 7 and the resistor 5, and when a continuous leakage current of a predetermined level flows through the resistor 5, it ignites due to the heat generated by the resistor 5, and a jet flow is ejected into the outer cylinder 2. The pyrotechnic agent 6 discolors the inside of the outer cylinder 2 and separates the first counter electrode 4a from the outer cylinder 2.
A deterioration display device for a lightning protection means, comprising: