JPH0524606B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention provides a method for sealing an insulating gas in a grounded tank,
The present invention relates to an earthing switch with a resistor, which constitutes an earthing switch equipped with a resistor inside.

[Prior art]

When grounding a cable, if you use a normal grounding switch, when the residual charge in the cable is discharged, a surge will occur in the cable core, which will be induced in the cable sheath, creating an induced voltage in the sheath. This is known to cause dielectric breakdown of the anti-corrosion layer of the sheath, resulting in holes. Therefore, as this type of grounding switch, a grounding switch with a closing resistor is used, which grounds the cable system through a resistor and suppresses surges by using the resistor. A conventional device of this type is shown in FIG. Figure 1 shows a phase-separated type. In Figure 1,
1 is a grounding tank, 2 is a fixed side electrode to which a cable is connected, 2a is a fixed side contact, 3 is a movable side electrode, 3a is a movable side contact, 3b is a movable contact, 3c is an insulating rod, 3d is a movable part 3 4 is a resistor, 4a is a ground wire for the resistor 4, 5a is a grounding blade, 5b is a ground side contact, 5c is a movable contact 3b, and a drive lever that linearly moves the insulating rod 3c and the grounding blade 5a. , 6 is a ground terminal for connecting the ground side contact 5b, and 7 is a ground bar.

Next, the operation will be explained. As shown in FIG. 2, as the drive lever 5c rotates, the movable contact 3b, insulating rod 3c, and grounding blade 5a simultaneously move linearly and come into contact with the fixed contact 2a. As a result, the residual charge on the cable is removed by the fixed contact 2a,
Movable contact 3b, movable electrode 3, resistor 4,
It is discharged through the ground wire 4a. At this time, a power-on surge corresponding to the AC voltage peak at the time of power-on occurs in the movable electrode, but it is insulated from the grounding plate 5a via the insulating rod 3c.

When the drive lever further rotates, the movable contact 3b moves to the fixed contact 2a as shown in FIG.
During this period, the grounding blade 5a contacts the movable contact 3a while sliding the grounding contact 5b with a required delay time, and the fixed electrode 2 contacts the movable contact 3b and the movable contact 3a.
a, grounding blade 5a, grounding side contact 5b,
It is grounded via the ground terminal 6. As a result, the resistor-equipped earthing switch has the ability to function as a normal grounding device, such as insulating megging and main circuit resistance measurement.

Conventional earthing switches with resistance are constructed as described above, and since the driving parts such as movable contacts and grounding blades move linearly on one axis, they require a large dimension L in the axial direction, and gas-insulated switching is required. When this resistor-equipped earthing switch is used as a part of the device, there are drawbacks such as an increase in overall dimensions such as the height direction.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the conventional ones as described above.The contact that inserts the resistor into the main circuit makes a linear movement, and the contact that makes the original ground makes a rotational movement. , the purpose is to shorten the required axial length and reduce the overall height of the device.

[Embodiments of the invention]

An embodiment of the present invention is shown in FIG. 4 below.

In the figure, 1 is a grounded tank filled with insulating gas such as SF ₆ gas, 2 is a fixed side electrode, 3 is a movable side electrode, 3
a is a movable side contact, 3b is a movable contact,
3c is an insulating rod, 3e is a connecting lever, 3f is a connecting link, 3g is a lever, and 4 is a resistor that supports the movable part 3, with one end connected to the movable part 3 and the other end connected to the ground tank 1. For example, a resistance element is covered with an organic insulating material such as FRP. 5a
5b is a grounding blade, 5b is a grounding side contact on which the grounding blade 5a rotates and slides, 7 is a grounding bar, 8 is a lever 3g and a frame that fixedly supports the grounding side contact 5b, and 9 is an insulated terminal. Reference numeral 10 designates a mechanical tank of the ground tank 1. 5 is a right side view of FIG. 4 showing only the supporting portion of the resistor 4. FIG.

Next, the operation will be explained.

By rotating the connecting lever 3e, the insulating rod 3
The movable contact 3b performs a linear movement via the lever 3c, and at the same time the grounding blade 5a performs a rotational movement via the connecting link 3f lever 3g. At this time, as shown in FIG. 6, during the operation, the movable contact 3b
contacts the fixed side contact 2a, and the residual charge of the cable is discharged via the fixed side electrode 2, the movable contact 3b, the movable part 3, and the resistor 4. At this time, the blade 5a is still in the middle of rotation when it touches the ground. After that, when the connecting lever 3e further rotates, the grounding blade 5a comes into contact with the movable contact 3a, as shown in FIG. 7, and the fixed electrode becomes in the normal grounded state.

In the above embodiment, a three-layer one-pack type device has been described, but a phase-separated type device may also be used, and the same effect will occur.

〔Effect of the invention〕

As described above, according to the present invention, the movable contact for applying resistance moves linearly, but the grounding blade that performs normal grounding is of a rotating type, so the axial dimension L' is extremely reduced, and the entire device The dimensions of are greatly reduced.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing the open state of a conventional earthing switch with a resistor, and Figures 2 and 3 show only the main parts of the device shown in Figure 1, showing the instantaneous closing state and the completed closing state. 4 is a sectional view showing an open state of the device in an embodiment of the present invention, FIG. 5 is a side view showing the main parts of FIGS. 5 and 4, and FIG.
7 and 7 are cross-sectional views showing the instantaneous closing state and the completed loading state of the device shown in FIG. 4. Note that the same reference numerals in the figures indicate the same or corresponding parts. 1...Grounded tank, 2...Fixed side electrode, 3...
Movable side electrode, 3a...Movable side contact, 3b...
...Movable contact, 3c...Insulating rod, 3d...Insulating spacer, 3e...Continuous lever, 3f...Connecting link, 3g...Lever, 4...Resistor, 4a...
...Earth wire, 5a...Grounding blade, 5b...Ground side contact, 5c...Drive lever, 6...Grounding terminal, 7...Grounding bar, 8...Base, 9...Insulated terminal.

Claims (1)

[Scope of Claims] 1. A fixed electrode and a movable electrode are provided facing each other in a grounded container filled with insulating gas, the movable electrode is at ground potential, and the fixed electrode is inserted through the movable electrode. In a grounding switch having a movable contact that makes contact with and separates from the movable contact, the movable electrode is supported by a resistor, and at the instant of the closing operation of the movable contact, the fixed electrode is grounded via the resistor, and after a required time, the movable electrode is supported by a resistor. A grounding switch with a resistor, characterized in that the fixed electrode is directly grounded by connecting a rotary grounding blade that moves with the contact to the movable part. 2. The earthing switch with a resistor according to claim 1, wherein the resistor has a resistive element covered with an organic insulating material such as FRP.