JPH0251232B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present 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 and inspected. The present invention relates to a deterioration display device that immediately provides a simple display that is clearly and reliably visible.

[Conventional technology]

As distribution networks grow in size and complexity,
For the purpose of protecting lines and equipment from lightning surges, etc.
Alternatively, a huge number of lightning arresters are installed for insulation coordination.

[Problem to be solved by the invention]

However, 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.

Conventionally, in order to quickly disconnect a deteriorated lightning arrester from the line, a structure has been considered in which the grounding side connection of the lightning arrester is dropped and disconnected when a leakage current of a certain level or more continues to flow. However, in this type of structure, the pressure inside the capsule is rapidly increased in order to obtain the operating force for dropping and separating, so the structure itself is required to be safe and must be handled with great care. Furthermore, considering the original purpose of installing lightning arresters, even if it were possible to automatically and quickly disconnect the grounding side of a deteriorated arrester, it would not be sufficient, and it would be necessary to eventually replace the deteriorated arrester with a new one. It is.

From the above-mentioned viewpoints, the present invention provides an accurate and simple deterioration display that is directly connected between lightning protection means such as a lightning arrester and the earth, and responds only to the continuously flowing earth leakage current. The purpose of the present invention is to provide a deteriorated display device. Another object of the present invention is to provide a deterioration display device that is integrally and compactly configured, is extremely easy to attach and detach from a lightning arrester, and is capable of ground discharge operation in response to multiple lightning even after deterioration of the lightning arrester is indicated. is also aimed at.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a deterioration display device connected in series to a lightning arrester such as a lightning arrester, in which a sealing member is disposed at both ends of a transparent outer cylinder, and a sealing member is provided at both ends of a see-through outer cylinder. A terminal with a proximal end of the cylindrical electrode fitted is inserted and fixed with a space provided at the inner end, and a discharge is caused between the inner peripheral surface of the tip of the cylindrical electrode and the outer peripheral surface of the inner end with respect to the other sealing member. A counter electrode forming a gap is inserted and fixed, a resistor is connected between the terminal and the inner ends of the counter electrode in the cylindrical electrode, and an ignition agent is arranged around the resistor,
When a continuous leakage current of a predetermined level flows through the ignition agent through the resistor and the resistor generates heat, it ignites, and after ignition, the pressure increases and is ejected to the outside of the cylindrical electrode through the space between the parts. , the gist is that the appearance of the outer cylinder is changed in color to indicate deterioration.

〔Example〕

The configuration of an embodiment of the present invention will be described below with reference to illustrative drawings. Reference numeral 1 denotes a lightning arrester connected in series with the deterioration display device I of the present invention, which is illustrated as one of general lightning arresting means. Reference numeral 2 denotes a see-through outer cylinder of the deterioration display device I; 3 is a cylindrical electrode whose outer surface is colored to indicate the normal state of the lightning arrester 1, for example, yellow; and 4 is a cylindrical electrode provided inside the outer cylinder 2; This is a counter electrode placed at a portion inserted into the tip of the cylindrical electrode 3. 5 is a terminal inserted into the base end of the cylindrical electrode 3, and the cylindrical electrode 3 and the terminal 5 are brought into partial contact to form a partial gap 3' from which the ignition agent, which will be described later, is ejected from between them. I try to do that. Reference numeral 6 denotes an insulating spacer that is fitted between the cylindrical electrode 3 and the counter electrode 4 and is fixed to the counter electrode 4, the end surface of which forms a creeping discharge gap 7 between the cylindrical electrode 3 and the counter electrode 4. I try to do that. (See Figure 5) A slight gap 3'' is formed between the cylindrical electrode 3 and the insulating spacer 6. 8 is between the terminal 5 and the counter electrode 4 within the cylindrical electrode 3. The heat-generating resistor connected to the device uses, in addition to normal electrical resistance, a PTC (positive polarity thermistor), which has a significant temperature dependence.
Reference numeral 9 denotes an ignition agent disposed around the resistor 8, which is selected from a material that causes a moderate pressure increase after ignition and exhibits a color different from the outer surface of the cylindrical electrode 3, for example, black. . The ignition temperature of the ignition agent 9 and the heat generation characteristics of the resistor 8 are selected so 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 8. It is. Reference numerals 10 and 10' designate spacers as a pair of sealing members that are fitted into both ends of the outer cylinder 2, and these spacers and the inner end of the outer cylinder 2 are bonded. Reference numerals 11 and 11' designate a pair of covers that are fitted onto both ends of the outer tube 2 and bonded to the outer surface end portions of the outer tube 2. In addition, in the portion where the terminal 5 and the counter electrode 4 penetrate the covers 11 and 11', respectively,
A seal is applied with a waterproof sealant (for example, manufactured by Shin-Etsu Chemical Co., Ltd., trade name "Silicon Sealant").

An example of the installation state of the deterioration display device I according to the present invention will be described with reference to FIG. One terminal 5 of the device I is connected, and the other counter electrode 4 of the deteriorated display device I is connected to a ground wire 16.

Next, the operation of the above configuration will be explained. Lightning arrester 1
When the deterioration of the lightning arrester 1 is slight and the ground leakage current is below a predetermined level, the cylindrical electrode 3 appears yellow through the outer cylinder 2, indicating that the arrester 1 is in a normal state.
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 7 rises rapidly, the discharge gap 7 causes creeping flash, and the discharge current flows through the surge arrester 1 and the discharge gap 7 to the ground. At this time,
Since the resistor 8 and the pyrotechnic agent 9 are configured to act thermally as described above, the pyrotechnic agent 9 remains unignited for a short period of time until the discharge gap 7 is entangled. Further, after creeping, the terminal voltage of the resistor 8 is kept low, so the ignition agent 9 similarly remains unignited. In this way, when the deterioration of the lightning arrester 1 is slight, the display device having the above-mentioned configuration continues to display the normal state of the lightning arrester 1 both when the lightning arrester 1 is operating and when it is not operating.

On the other hand, when the continuous leakage current to ground of the arrester 1 reaches the predetermined level due to several discharges of the arrester 1 or due to deterioration over time, the ignition agent 9 is ignited by the Joule heat generated in the resistor 8, and the ignition agent 9 is first ignited. This causes a pressure increase inside the cylindrical electrode 3, which immediately becomes a black jet flow through the gaps 3' and 3'' and fills the outer cylinder 2, and the fine combustion products are deposited on the inner surface of the outer cylinder 2 and the cylindrical electrode. As a result, the exterior of the outer cylinder 2 becomes black, indicating the deterioration state of the lightning arrester 1.If PTC is used as the resistor,
The resistance value of the display device in a normal state can be kept low.

Moreover, even after the deterioration of the lightning arrester 1 is displayed,
Since this deteriorated display device I has a discharge gap 7 formed between the counter electrode 4 and the cylindrical electrode 3, the lightning surge current that has entered due to multiple lightning strikes is discharged to the ground through the discharge gap 7.

〔Effect of the invention〕

As detailed above, the present invention provides a deterioration display device connected in series to a lightning arrester such as a lightning arrester, in which a sealing member is disposed at both ends of a transparent outer cylinder,
A terminal fitted with the proximal end of the cylindrical electrode is inserted and fixed into one of the sealing members with a space provided at its inner end, and the terminal is inserted and fixed into the other sealing member with a space between the inner ends of the cylindrical electrode and the inner peripheral surface of the tip of the cylindrical electrode. A counter electrode that forms a discharge gap is inserted and fixed between the outer peripheral surfaces of the inner ends, and a resistor pair is connected between the terminal and the inner ends of the counter electrode within the cylindrical electrode, and ignition occurs around the resistor. When the igniting agent is placed in the resistor and a predetermined level of continuous leakage current flows through the resistor and the resistor generates heat, it ignites.After the ignition, the pressure increases and the cylindrical electrode By ejecting to the outside and discoloring the external appearance of the outer cylinder to indicate deterioration, when the arrester 1 receives a shock wave from lightning or the like in its normal state or is on standby, the display device displays the normal color. When the value of the leakage current to ground exceeds a predetermined level due to deterioration of the arrester, the appearance of the outer cylinder 2 will be an abnormal color as a result of the ignition of the ignition agent 9 caused by the heat generated by the resistor 8. After quickly detecting an abnormal lightning arrester, it can be removed and replaced with a new one. This has the advantage that the substation ground fault relay can be prevented from operating multiple times due to a ground fault caused by neglecting a deteriorated lightning arrester.

Further, as described above, since the deterioration display device according to the present invention is formed as a single unit, compact and has a simple structure, it is both practical and economical in that it is extremely easy to attach and detach from the lightning arrester 1.

Further, since the deterioration display device I according to the present invention has a configuration in which a discharge gap 7 is formed between the counter electrode 4 and the cylindrical electrode 3, even after the deterioration of the lightning arrester 1 has been indicated, the deterioration display device I according to the present invention can be used even after the deterioration of the lightning arrester 1 is indicated. In response to the lightning surge current, a ground discharge operation can be performed through the discharge gap 7.

[Brief explanation of the drawing]

FIG. 1 is a basic circuit configuration diagram of a degraded display device of the present invention, FIG. 2 is a longitudinal cross-sectional view showing an embodiment of the degraded display device of the present invention, and FIG. 3 is a cross-sectional view taken along line A-A in FIG. FIG. 4 is a cross-sectional view taken along the line BB, FIG. 5 is an enlarged view of a main part showing a discharge gap, and FIG. 6 is a diagram showing one mode of use. 1... Lightning arrester, 2... Outer cylinder, 3... Cylindrical electrode,
3'...Partial gap, 3''...Gap, 4...Counter electrode, 5...Terminal, 7...Discharge gap, 8...Resistor, 9...Ignition agent, 10, 10'...Sealing member Spacer as I...Deterioration display device.

Claims (1)

[Claims] 1. In a deterioration display device connected in series to a lightning arrester such as a lightning arrester, sealing members 10, 1 are provided at both ends of a transparent outer cylinder 2.
0', and a terminal 5 with a base end of the cylindrical electrode 3 fitted therein is inserted and fixed into one sealing member 10 with a space 3' provided at its inner end, and the other sealing member 10 ′, the cylindrical electrode 3
A counter electrode 4 forming a discharge gap 7 is inserted and fixed between the inner peripheral surface of the tip end and the outer peripheral surface of the inner end thereof, and the terminal 5 and the counter electrode 4 are inserted and fixed within the cylindrical electrode 3.
A resistor 8 is connected between both inner ends of the resistor 8, and an incendiary agent 9 is arranged around the resistor 8, so that a continuous leakage current of a predetermined level flows through the resistor 8 and the initiator 9 flows through the resistor 8. 8 ignites when it generates heat, and after the ignition, the pressure increases and is ejected to the outside of the cylindrical electrode 3 through the portion 3', causing discoloration of the external appearance of the outer tube 2. Deterioration display device for lightning protection means.