JPS644197Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a switch with a built-in surge arrester that has a lightning current measuring section that enables checking the lightning current discharged by the surge arrester.

A compact switch with a built-in lightning arrester using non-driving elements such as Zno has already been proposed. When using this switch with a built-in lightning arrester, it is necessary to properly evaluate the lightning protection effect under actual usage conditions in order to prevent lightning damage. In that case, in this switch with a built-in lightning arrester, even if there is actually a discharge of lightning current, if the discharge is less than the withstand capacity of the built-in arrester, no history will be left, and even if there is no lightning damage, the cause of the discharge will not be left. There was a drawback that a fair evaluation could not be made because it could not be determined whether this was due to the lightning protection effect of the built-in lightning arrester or because there was no lightning itself.

On the other hand, a magnetic tape that has been magnetized in advance with a predetermined high-frequency magnetic field is placed at right angles to the grounding wire of a switch with a built-in lightning arrester, and the magnetic tape is demagnetized by the electric field created around the grounding wire by the discharge of lightning current. Among them, a method of measuring the magnitude of the lightning current has been considered, but this method had the following drawbacks.
The lightning current of a switch with a built-in lightning arrester is shunted through the switch's grounding wire and the switch body to the grounding wire of the cross arm and the reinforcing bars of the concrete column, so if only the grounding wire of the switch is measured, the lightning current will not be detected. The disadvantage is that it is not possible to know the value of the current. In addition, since the magnetic tape is attached midway through the grounding wire, it obstructs the raising and lowering of the utility pole, which is unfavorable in terms of workability for power distribution work and has the disadvantage of detracting from the aesthetics.

The present invention was developed in view of the above, and it is possible to not only know whether or not lightning current is being discharged from the built-in lightning arrester, but also to accurately know the value of lightning current, and as a result, to obtain a fair evaluation of the lightning protection effect. It is an object of the present invention to provide a switch with a built-in lightning arrester having a lightning current measuring section that can improve the structure of the pole and reduce the complexity of mounting the pole.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

A switch with a built-in lightning arrester having a lightning current measuring section according to an embodiment of the present invention shown in FIG. Ground wire 2
It has a lightning current measuring section 300 connected through 02.

The entire switch is suspended from a hanging member 101 by hanging bolts 102, and the switch main body 100 has a lid 103 on the top and track side terminals 104 and 105 on both sides. The line side terminal 104 extends into the switch main body 100 via a bushing 106, and is connected to a fixed contact 108 located inside an arc extinguishing chamber 109 via a contact support conductor 107.
The track side terminal 105 has exactly the same structure, and the rotary insulator 1 is connected by the movement of the handle 111.
The rotational motion transmitted through the connecting conductor 11
2 and movable contacts 1 provided at both ends of the movable contact 1
Electrical switching is performed between line side terminals 104 and 105 via 10.

Each lightning arrester 200 includes one or more ZnO
Elements, etc. are arranged in series, one end of which is connected to the contact support conductor 107 by a connecting conductor 201 for each phase directly or via a series gap, and the other end is connected to each phase individually or all phases at once. It is connected to a grounding terminal 205 of the switch main body via a grounding wire 202, a lead-out grounding wire 302, a connecting grounding wire 203, and a grounding terminal 204 common to each phase.

FIGS. 2A, 2B, and 2C are enlarged explanatory views of the lightning current measurement unit 300 provided for each phase or all phases, and is installed so that it can be opened and closed using the mounting bracket 308 of the switch main body 100 as a fulcrum. A cover 303 is fixed by a fixing fitting 310, and a wire is arranged inside the cover 303, and one end is connected to the connecting grounding wire 202 of the lightning arrester 200 via a grounding pull-out bolt 304, and the other end is connected to the connecting grounding wire 202 for each phase via the connecting grounding wire 203. A grounding wire 302 connected to the ground terminal 204 of the switch body and the ground of the switch body, a magnetic tape 301 placed between the grounding wire 302 and the cushion material 309 and magnetized in advance with a predetermined high-frequency magnetic field, and a rubber, etc. An insulating plate 305 integrally arranged on a cushion material 309, a switch main body 100 and a lead-out grounding wire 3
02 and the drawer ground bolt 304, and a packing 307 provided between the insulating spacer 306 and the switch main body 100 are shown.

In the above configuration, when the built-in arrester is activated by a lightning strike, all the lightning current flows to the lead-out grounding wire 302, and the magnetic tape 30 in contact with the lead-out grounding wire 302 is
The waveform previously magnetized to 1 is demagnetized. The demagnetized length l is measured, and the peak value of the lightning current can be accurately calculated from that value, allowing for a valid evaluation of the lightning protection effect.

In addition, the inside of the switch main body 100 and the lightning current measuring part cover 3
Since the inside of the magnetic tape 301 is completely sealed with a gasket 307, etc., the magnetic tape 301 can be easily replaced or fixed without removing and opening the switch body, and the switch remains installed. You can check lightning current.

Furthermore, the lightning current measuring part connected to the lightning arrester is integrated into a predetermined part of the switch body so that only the magnetic tape can be removed and fixed at will, without having to disconnect the grounding wire. It is possible to simplify the pillar by eliminating the work such as wiring and mounting.

[Brief explanation of drawings]

Fig. 1 is a configuration explanatory diagram showing an embodiment of the present invention, Fig. 2 A, B, and C are enlarged views of the lightning current measuring section shown in Fig. 1, in which A is a front view, B is a side view, C is a sectional view taken along straight line A-A in A. Explanation of symbols, 100...Switch body, 101...
...Hanging member, 102... Hanging bolt, 103...
Lid, 104, 105... Track side terminal, 106...
Bushing, 107...Contact support conductor, 108...
... Fixed contact, 109 ... Arc extinguishing chamber, 110 ... Movable contact, 111 ... Handle, 112 ... Connection conductor, 113 ... Rotating insulator, 200 ... Lightning arrester, 2
01... Connection conductor, 202, 203... Connection grounding wire, 204... Common grounding terminal for each phase, 205... Switch body grounding terminal, 300... Lightning current measuring section, 3
01...Magnetic tape, 302...Outgoing ground wire,
304...Grounding drawer bolt, 305...Insulating plate, 306...Insulating spacer, 307...Punkin, 308...Mounting metal fittings, 309...Cushion material, 310...Fixing metal fittings, 303...Metallic cover.

Claims (1)

[Scope of utility model registration request] In a switch having a built-in lightning arrester in a sealed main body, one end of which is connected to the track side terminal and the other end commonly connected to the grounding side connecting ground wire for all phases, the connecting ground wire is insulated from the closed type main body. In addition, a grounding wire that is airtightly drawn out individually or all at once and then connected to the grounding terminal of the sealed body, a magnetic tape that is removably in contact with the grounding wire, and a magnetic tape that can be opened and closed. A switch with a built-in lightning arrester, characterized in that it has a lightning current measuring part configured with a metal cover that can be freely covered.