JPS5936484B2 - Breaker with earthing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a grounding device, particularly attached to a breaker, which is grounded at a disconnection position of a placement board via one side of a fixed disconnection section on the power supply side or the load side.

Generally, a power supply side and a load side fixed disconnecting section connected to a power supply bus and a load are installed in a power distribution board, for example, a cubicle.

A movable disconnect terminal is attached to the breaker that goes in and out of the cubicle.

The breaker is moved into the cubicle and the operating position is where the movable disconnect terminal is connected to the fixed disconnect section, and the breaker is moved toward the outside of the cubicle and the fixed disconnect section is connected to the movable disconnect terminal. There is a disconnection position that is not connected.

On the other hand, when performing maintenance and inspection on various electrical devices placed on the load side of the system, move the circuit breaker to the disconnection position and ground the fixed disconnect section on the load side via the grounding device. Even if a voltage is applied to the equipment, it is grounded through the grounding device to prevent workers from receiving an electric shock during maintenance and inspection.

Various kinds of grounding devices are used.

These can be roughly divided into (a) those that directly insert a short-circuit conductor to ground the system only when there is no voltage in the system to be grounded, and (b) those that force a short-circuit current equivalent to the short-circuit capacity of the system. There are some that use a device that can be used to ground the ground, and others.

For type (a), simply prepare a short-circuiting conductor with wheels attached, pull out the breaker in the system to be grounded outside the cubicle, and then use this grounding conductor instead. In some cases, a disconnect switch for switching the ground is built into the cubicle from the beginning, and the system is grounded by operating the disconnect switch.

All of these are used to ground non-voltage systems.
In the unlikely event that voltage jumps in from the outside while grounding,
Although the short-circuit current can be safely passed to the ground bus and the voltage applied to the system can be suppressed, if this type of grounding device is inserted into a system where voltage is being applied by mistake, it will force the system to short-circuit. The electromagnetic repulsion caused by the short-circuit inrush current at the time of the accident will cause the grounding device to be blown off, causing an arc to be blown at the contact area and burning out the inside of the cubicle, which is also extremely dangerous for the operator of the grounding device.

Therefore, although type (a) is inexpensive, it is inferior in safety.

Type (b) is generally a breaker that has the same shape and function as the circuit breaker used in the system.
Among the fixed disconnecting sections on the power supply side or the load side, the fixed disconnecting section portions that are not grounded are directly connected to the ground bus bar.

Since this has the same closing ability as a circuit breaker, even if a system to which voltage is applied is accidentally grounded, it will not be rejected and can be safely grounded.

Therefore, although the safety of type (b) is extremely high, it is as expensive as a circuit breaker.

As a method to realize the type (b) type of grounding device at a lower cost, attach an adapter to the breaker used in the system and modify it to a grounding device.After the grounding work is completed,
There is a method of removing this adapter and using it again as a breaker, but it takes time and effort to attach and detach the adapter, making it inconvenient.

An object of the present invention is to provide a grounding device attached to a breaker that is easy to perform grounding work and highly safe, by incorporating a grounding blade into the breaker and making it possible to ground the system at the disconnection position of the breaker. It is about providing.

In the grounding device of the present invention, the grounding blade provided on the breaker can be operated only when the breaker is located outside the power distribution board, and by inserting it again into the disconnection position within the power distribution board, the grounding blade can be moved to the load side. Since it is connected to one side of the fixed disconnect section on the power supply side and grounded via a breaker, it not only makes it easier to disconnect the ground, but also
Grounding work is safe.

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

1 and 2 are diagrams showing the breaker 1 housed in a cubicle.

A breaker such as a vacuum breaker, a gas breaker, an oil-filled breaker, etc., for example, an oil-filled breaker 1, has a pair of electrodes (not shown) arranged inside an insulating cylinder 2, and these electrodes are supported by a trolley 3. Operate the operating mechanism section (not shown) housed in the operation box 4 and move one side of the conductive rod (not shown) provided on the electrode upwards and downwards to open and close the electrode. do.

A support insulator 4A that supports the breaker is interposed between the breaker 1 and the operation box 4.

Insulating cylinder 2 insulated from the conductive rod to supply current to the electrode
Upper and lower terminals 7, 8 are attached to flanges 5, 6 attached to both ends of the terminal.

These terminals are connected to power supply side and load side fixed disconnect sections 9, which are attached to insulating plates (not shown) in the corresponding cubicles.
Open and close with 10.

To open/close, move breaker 1 in the direction of arrow A in the cubicle.
Move to.

When the upper and lower terminals 7 and 8 are not in contact with the power supply side and load side fixed disconnection parts 9 and 10, at disconnection position B,
When connected, it is in operating position C.

The grounding device 11 attached to the operation box 4 is configured as follows.

That is, the main shaft 13 is arranged between the support members 12 mounted on the operation box, and the plurality of first, second and third levers 14.degree. 15.16 and the operation bundle 17 are attached to the main shaft.

The second lever 15 is connected to the upper terminal 7 via an insulated operating rod 18.
The grounding blade 19 is connected to the grounding blade 19 attached to the grounding blade 19 .

A tension spring 20 disposed between a pin 15A provided on the second lever 15 and a pin 12A provided on the support member 12 causes the operation bundle 17 to rotate downward (toward the operation box) or upward from the horizontal state. When moving, it functions to rotate the main shaft 13 clockwise and counterclockwise.

A book pin 21 provided with the third lever 16 engages with a blocking surface of a regulating plate 22 disposed corresponding to the third lever.

The regulating plate 22 is attached to an inner wall surface of the cubicle (not shown).

The stepped portion 23 provided on the lower side of the regulation plate is at the disconnection position B,
The left side of this, that is, the inside of the cubicle, is the operating position C.
It is.

A fixing screw 24 is screwed into the support member 12 through the third lever 16 in order to hold the grounding blade 19 in a predetermined position after operation.

The ground contact 25 installed on the floor of the switchboard is
At the disconnection position B, the circuit breaker 1 comes into contact with a grounding shoe 26 attached to a metallic rear end 2B attached to the lower end of the insulating tube.

Next, a case in which the grounding device 11 is grounded will be described.

The breaker 1 in the operating position C in FIG.
When the main shaft 13 is rotated counterclockwise via the support member 12, the third lever 16 and the insulated operating rod 18 are lifted upward from the horizontal state shown in FIG. 1 to the state shown in FIG.
The grounding blade 19 is placed in a horizontal state via the grounding blade 19 .

When the circuit breaker 1 is moved within the cubicle in this state, the block pin 21 engages with the stepped portion 23 via the third lever 16.

That is, the circuit breaker 1 stops at the disconnection position B, and the grounding blade 19 connects to the load-side fixed disconnection section 9.

Therefore, even if voltage is present on the load side, when the breaker is turned on, the current in the load side fixed disconnect section 9 will flow from the grounding blade 19 to the upper terminal 7 to the breaker 1 (flange 5
→ Rod → Electrode → Flange 6 → Rear end 2B) → Ground shoe 26 → Grounded via ground contact 25.

Therefore, the grounding ability is the same as the closing ability of a circuit breaker, making it extremely safe.

In this way, in the present invention, the grounding blade can be connected to the load-side fixed disconnect section and grounded via the breaker by simply operating the operation handle provided on the breaker and inserting the breaker into the disconnection position. , making grounding work easier.

In addition, although the case where the grounding blade is connected to the load side fixed disconnecting section has been described above, the grounding blade may be connected only to the power supply side fixed disconnecting section.

Furthermore, the breaker is equipped with an interlink mechanism that prevents it from being inserted into the cubicle unless it is in the disconnected state, so it is impossible to accidentally bring the breaker to the grounded state with it turned on. , extremely safe.

That is, in the grounded state where the block pin 21 and the stepped portion 23 are engaged as shown in FIG. 2, the breaker 1 cannot be moved from the disconnection position B to the operating position C.

Furthermore, even if an attempt is made to drive the operation handle 17 downward when the circuit breaker is in the grounded state at the disconnection position B, the block pin 21 is restricted by the upper surface of the stepped portion 23 and cannot be lifted. There is no risk of the grounding blade 19 being removed by mistake.

Furthermore, when the breaker is in the operating position C shown in FIG. 1, that is, even if the grounding blade 19 is accidentally tried to fall horizontally during operation, the blocking surface of the regulating plate 22 and the block pin 21 will engage. It cannot be operated because it is

In other words, the operation handle 17 must be operated with the breaker taken out of the cubicle, and erroneous operation can be reliably prevented.

In addition, although the example of a horizontal draw-out type breaker was explained above, it goes without saying that the grounding device of the present invention can also be used in a vertical type breaker.

As described above, according to the present invention, the breaker is provided with a grounding device to facilitate grounding work, making maintenance and point verification work easier.

[Brief explanation of the drawing]

1 and 2 are perspective views of a breaker with a grounding device shown as an embodiment of the present invention. 1... Breaker, 7, 8... Movable side disconnecting terminal, 9 and 10... Power supply side and load side disconnecting section, 11... Grounding device. , 19...
grounding blade.

Claims (1)

[Scope of Claims] 1. Fixed disconnecting sections on the power supply side and the load side provided in the switchboard, a trolley supporting a breaker having a movable terminal, and the movable terminal and the fixed disconnecting section are in electrical contact with each other. Operating position and electrically non-contact disconnection position, and a grounding blade that opens and closes with the fixed disconnection section by operating one side of the movable terminal in the disconnection position, and grounding through the above-mentioned grounding blade and breaker. In those equipped with a grounding device, ■
A support part for the grounding device established on a truck, a main shaft rotatably supported by the support part, first and second levers provided on the main shaft, and an operation bundle for rotating the main shaft. an insulated operating rod that engages with the first lever and moves according to the rotation of the main shaft; and a grounding blade that engages with the insulated operating rod and opens and closes with the fixed disconnecting section in accordance with the movement of the insulated operating rod. , ■ A block pin extending in the direction of the regulating plate of the switchboard attached to the second lever, the regulating plate engages with a block pin formed at a location corresponding to the operating position, and the grounding blade extends in the direction in which it connects with the fixed disconnecting section. A stage that engages with a blocking surface that prevents rotation of the operating bundle and a block pin formed at a location corresponding to the disconnection position of the regulating plate, and that prevents rotation of the operation bundle in a direction in which the grounding blade moves away from the fixed disconnection section. A breaker with a grounding device characterized by comprising: and.