JPS5915060Y2 - Current transformer - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a current transformer installed and used in a closed switchboard or the like.

FIG. 1 shows a general elevating type automatic connection type closed switchboard, and its configuration is as well known, with the inside of the panel frame 10 being
A breaker chamber 12 that houses the breaker 11 in a manner that can be raised and lowered; a bus chamber 14 that is located above the breaker chamber 12 and houses the bus conductor 13; Cable room 16 located above and behind the breaker room 12 and housing the cable 15 for external connection
It is divided into

In such a closed switchboard, a current transformer 17 for detecting the main circuit current is generally installed in the cable room 16 on a horizontal conductor 18 connected to the cable 15, and this current transformer The secondary side of the device 17 is connected to a control circuit via a terminal block (not shown) provided on the front side of the panel frame 10, that is, on the left side in the drawing.

The reason why the terminal block and the control circuit described above are arranged on the front side of the panel frame 10 is to facilitate the test 9 inspection, and most closed switchboards are constructed in this way.

By the way, the secondary terminal 9 of the current transformer 17 is connected to 1 as shown in the figure.
Generally, it is provided in a direction parallel to the secondary conductor 18, and in this case, the secondary circuit is once placed in the cable room.
After being pulled out to the rear of the 6, it is connected to a terminal block, etc. in the front, so routing it is troublesome.

Also, during installation or subsequent inspection, please
9 must be opened from the rear of the panel frame 10, making it inconvenient to deal with terminal blocks and control circuits arranged in front of the panel frame 10.

In addition, this work is actually difficult because the cable 15 must be avoided after the cable 15 is connected, and furthermore, if the cable 15 side becomes the power supply side, inspection at the time of power application becomes impossible.

On the other hand, when connecting current transformers provided for each phase to configure a zero-phase detection circuit or a common circuit for each phase,
Alternatively, in the case of a row-by-panel configuration, if a wiring duct passing through the upper part of the panel frame 10 is used to connect other panels, or if a secondary circuit is drawn out to this wiring duct, the secondary terminals should be placed horizontally as shown in the figure. The above-mentioned configuration arranged in the same direction is advantageous because it is easier to connect than other configurations.

When installing a current transformer in a closed switchboard like this, due to its installation condition and relationship with other equipment, the conventional method of arranging the secondary terminals in one direction has advantages and disadvantages in terms of connection work and inspection. , was not completely satisfactory.

The capacity of closed switchboards is increasing year by year, and on the other hand, it is desirable that the external shape be as compact as possible, and the space inside the panel is extremely limited.

Therefore, improving the connection of storage equipment and the efficiency of inspection work has become a major problem.

The purpose of this invention is to place the secondary terminals in two different locations in different directions so that the secondary circuit can be easily connected and inspected even when installed in a limited space such as in a closed switchboard. An object of the present invention is to provide a current transformer for a closed switchboard.

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4.

In the figure, 20 indicates an embodiment of the current transformer according to the present invention, and this current transformer 20 is basically similar to a general current transformer, with a primary conductor 21 passing through the inside. A secondary winding (none of which is shown) is wound around the outer circumference of the iron core, and these are covered with an insulating material, and the outlet terminals of the secondary winding are further connected to the primary conductor on the surface of the insulating material. In addition to the outlet terminal 22 provided on the end surface so as to be substantially parallel to the primary conductor 21, the outlet terminal 23 provided on the peripheral surface in a direction substantially orthogonal to the primary conductor 21 is arranged. It is constructed by branching the lead wires and connecting them to each other.

Particularly, since the outlet terminal 23 of this current transformer 20 is provided on the bottom surface which is a part of the circumferential surface, if this current transformer 20 is attached to the panel frame in a closed distribution board via the support plate 25, the support plate 25 will be removed. It is arranged so as to pass through the opening of No. 25 and face downward.

With this configuration, even when applied to a power distribution board as shown in FIG. 1, an inspection window is provided in the ceiling corresponding to the breaker room 12 and can be opened and closed as shown in FIG. 2. cover 2
7, the inspection work can be done by opening this cover 27 and
This can be done from inside the breaker room 12 through the inspection window,
Correspondence with the terminal block and control circuit arranged on the front side of the panel frame 10 can be easily performed, and inspection work is much easier.

During inspection work, it is necessary to pull out the breaker 11 from the breaker room 12, but when testing or inspecting current transformers, connected terminal blocks, or control circuits, in most cases the breaker Since the circuit 11 is tripped and the electric circuit is left open, there is no problem in pulling it out of the panel frame 10, and the operation is easy.

In addition, the inspection window allows the breaker room 12 and the cable room 16 to be
Although a part of the space between the closed switchboard and the closed switchboard is opened, this inspection window is covered by a cover 27 except during inspection, and does not affect the closed class of the closed switchboard.

Furthermore, the secondary circuit of the current transformer 20 is routed as shown in Figs. 3 and 4, rather than being partially drawn out to the rear of the cable room 16 and then connected to the front terminal block or control circuit as in the conventional case. As shown in the figure, since the distribution line duct (30) installed vertically can be drawn out into the breaker chamber 12, connection to the terminal block and control circuit arranged on the front side of the panel frame 10 is easy. It will also be easier to route.

In addition, in order to connect each phase current transformer to each other or to connect to another panel, it is sufficient to use the conventional terminals 22 arranged in the direction of the end face, which is easier to connect. Ease of work is not impaired.

As described above, according to the present invention, in a current transformer installed in a narrow space such as a closed switchboard, the secondary terminals are arranged at two locations where the directions of the outer surface of the current transformer are almost orthogonal to each other. This makes it easy to deal with the highly restrictive installation conditions in closed switchboards and relationships with other devices, simplify the connection configuration, and facilitate connection work and test/inspection work. can.

[Brief explanation of drawings]

Figure 1 is a side configuration diagram showing a conventional current transformer installed in a closed distribution board; Figure 2 is a side configuration diagram showing an embodiment of the current transformer according to the present invention installed in a closed distribution board; FIG. 3 is an enlarged side view showing an embodiment of the current transformer according to the present invention, and FIG. 4 is a front view of FIG. 3. 20...Current transformer, 22.23...Secondary terminal.

Claims (1)

[Scope of utility model registration request] A secondary winding is wound around the outer periphery of an iron core whose inside is penetrated by a primary conductor, and the secondary winding and the iron core are covered with an insulating material, and is installed in a closed switchboard via a support plate. In the current transformer for a closed switchboard, the first outlet terminal is arranged on the surface of the insulating material in a direction substantially perpendicular to the primary conductor and facing the opening of the support plate; A current transformer for a closed switchboard, characterized in that a second outlet terminal is provided substantially parallel to the conductor, and the outlet wire of the secondary winding is branched and connected to each outlet terminal. .