JPS605697Y2 - Drawer type switchboard - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a pull-out type switchboard that allows insulation resistance measurement on the load side to be performed from the front.

A conventional drawer-type switchboard looked like the one shown in Figure 1.

The figure shows the box body of the board with the side plates removed. 1 is the box body of the board, 2 is the front door, 3 is the back cover attached to the back of the box body 1, and 4 has wheels 5 and a drawer waist. The cart is housed in a pushable manner, and a protective cover 6 is attached to the front.

An electromagnetic contactor 7, a power fuse 8 (the support frame is not shown), a power disconnection contact 9, and a load disconnection contact 10 are mounted on the truck 4.

11 is a power supply side contact terminal, 12 is a load side contact terminal, 13,
14 and 15 are support insulators, and 16 is a load cable.

Next, the operation will be explained.

A power supply disconnector contact 9 and a load disconnector contact 10 are provided on the trolley 4, and when the trolley 4 is pushed in and pulled out, these disconnector contacts 9 and 10 simultaneously connect to contact terminals 11, respectively. And 12 people come into contact with or leave.

Since the conventional pull-out type switchboard is constructed as described above, when measuring the insulation resistance of a load, when the cart is pulled out, the load disconnector contact 10 also separates from the load-side contact terminal 12.

Therefore, to measure the insulation resistance on the load side, it is necessary to pull out the cart 4 from the front of the panel, go to the back, remove the back cover 3, and measure the insulation resistance at the contact terminal 12, which is a cumbersome task.

This invention was made in order to eliminate the drawbacks of the conventional ones as mentioned above.
Provided is a pull-out type switchboard that can measure insulation resistance on the load side from the front of the panel so that when the trolley is pulled out and moved to the test position, the load disconnector contact and the load-side contact terminal are brought into contact by the auxiliary contact piece. It is intended to.

An embodiment of this invention will be described below with reference to the drawings.

Figure 2 shows the trolley 4 moved to the test position;
5 and 7 to 16 are the same as the above-mentioned conventional device.

Reference numeral 18 denotes an auxiliary contact piece, which is attached to the load circuit section contactor 10 mounted on the support insulator 17, and its tip is in contact with the load side contact terminal 12.

Further, the electromagnetic contactor 7 is attached to the front side of the truck 4.

A power fuse 8 is provided at the rear of the electromagnetic contactor 7, and a power disconnection contact 9 is provided at the rear of the power fuse 8.

Connection part 2 between the electromagnetic contactor 7 and the load disconnector contact 10 side
1 is provided on the front side of the electromagnetic contactor 7, so that the insulation resistance on the load side can be measured from the front of the panel.

A measurement window 19 is provided in a part of the protective cover 6 to enable safe measurement of insulation resistance, and the cover 20 is always closed.
It's closed.

To measure the insulation resistance, the trolley 4 is in the pushed position,
It is dangerous to simply open the electromagnetic contactor 7.

This is because there is a risk that the electromagnetic contactor 7 may be electrically turned on by other working tools without the user's knowledge during insulation resistance measurement.

Another reason is that even if the electromagnetic contactor 7 is opened, the gap between the opened contacts is small, about 30 TrDn, and the potential on the primary side (power supply side) induces it on the secondary side (load side). This is because voltage may be induced.

For this reason, as shown in FIG. 2, by opening the electromagnetic contactor 7 and pulling out the trolley 4 to the test position, the power supply disconnection contact 9 and the load circuit contact 10 are disconnected, making it safe. We are trying to

In this way, even when the trolley 4 is pulled out to the test position, the auxiliary contact piece 18 keeps the load disconnector contact 10 in contact with the load side so that insulation resistance is performed with the contacts 9 and 10 in the disconnected state. The terminal 12 side is connected in contact with the terminal 12 side.

FIG. 3 shows a state in which the disconnecting contact 10 is in contact with the contact terminal 12 due to the pushing of the cart 4, and the tip of the auxiliary contact piece 18 is in contact with the contact terminal 12.

To measure the insulation resistance on the load side, as shown in FIG. 2, pull out the trolley 4 to the test position and measure it at the connection part 21 at the other end of the connection wire of the disconnection part contactor 10 through the movement measurement window 19. .

FIG. 4 shows another embodiment of this invention, in which the auxiliary contact piece 18
is attached to the load-side contact terminal 12, and its tip is in contact with the disconnection contact 10 at the test position and push-in position of the trolley 4 shown in the figure.

In this way, the auxiliary contact piece 18 may be attached to either side of the contactor 10 or the contact terminal 12 of the load disconnecting section, and its tip is in contact with the other side at the test position.

In the case of a three-phase circuit load, the three phase wires are electrically connected to each other depending on the load equipment, so the auxiliary contact piece 18 may be provided for one phase.

As described above, according to this invention, an auxiliary contact piece is provided at the load disconnection section, and when the trolley is pulled out and moved to the test position,
Since the auxiliary contact piece is brought into contact with the load circuit section contactor and the load side contact terminal, the insulation resistance on the load side can be easily measured from the front of the tray, improving work efficiency.

[Brief explanation of drawings]

Fig. 1 is a schematic side view showing a conventional drawer-type switchboard excluding the side plate of the box body, Fig. 2 is a schematic side view corresponding to Fig. 1 of a drawer-type switchboard according to an embodiment of this invention, and Fig. 3 2 is an enlarged view showing the contact state of the load disconnecting section in FIG. 2, and FIG. 4 is an enlarged view corresponding to FIG. 3 of the load disconnecting section showing another embodiment of this invention. 1...Disc box body, 4...Dolly, 6...
...Protective cover 7...Magnetic contactor, 8.
...Power fuse, 9...Power supply disconnection contact, 10...Load circuit contact, 12.
...Load side contact terminal, 18...Auxiliary contact piece, 19...Measurement window, 20...Cover. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Scope of utility model registration request] A trolley that is housed in the box of the switchboard and can be pulled out and pushed in to the front, an electromagnetic contactor installed on the front side of this trolley, a power fuse arranged on the rear side of this electromagnetic contactor, and a power supply. A power supply disconnector contact, which is installed at the rear of the fuse, closes the power supply side when the trolley is pushed in, and opens the circuit when the trolley is pulled out.A power supply disconnector contact, which is installed at the rear of the trolley, closes the load side when the trolley is pushed in, and opens the circuit when the puller is pulled out. A load disconnection contact is provided between the load disconnection contact and the corresponding load side contact terminal, and when the cart is in the test position, the load disconnection contact and the load side contact terminal are interposed between the load disconnection contact and the load side contact terminal. an auxiliary contact piece for making a contact connection, a connecting part placed at the front of the electromagnetic contactor to connect the electromagnetic contactor side and the load disconnection contact side, and a measurement window attached to the front of the cart. A pull-out type switchboard equipped with a protective cover so that insulation resistance on the load side can be measured from the front side of the board at the connection part.