CN201387994Y - Building block type power distribution cabinet with grounding knife switch - Google Patents

Abstract

The utility model discloses a take cordwood system switch board of ground connection plug-in strip, its main technical scheme is: the power distribution cabinet adopts a structure of a double-building-block type protection switch and secondary protection, and comprises a primary main protection loop, a secondary branch protection loop, a lower double-head isolating switch, an upper end of the lower double-head isolating switch is connected with a low-voltage bus of a power transmission line, and a lower end of the lower double-head isolating switch is grounded. By adopting the technical scheme, double comprehensive protection is realized, secondary wiring is reduced, and the product performance is more perfect; the air circuit breaker is used as a main switch, so that the breaking capacity is high, and the breaking time is accurate; the grounding knife switch of the transformer substation is introduced, the potential safety hazard of the grounding wire arranged in the low-voltage power distribution cabinet is eliminated, the protection of personnel and the safety of equipment are improved, and the grounding operation of an operation site is simple, quick and reliable.

Description

Building block distribution cabinet with grounding knife

technical field

The utility model belongs to the technical field of low-voltage power supply, and relates to low-voltage power distribution equipment in a low-voltage power supply system. More specifically, the utility model relates to a building block type power distribution cabinet with a grounding knife.

Background technique

Low-voltage power distribution equipment is responsible for completing power control, protection, measurement, conversion and distribution in the low-voltage power supply system. It involves all aspects of national construction and people's lives. Its development is closely related to the development of national economy, science and technology and people's living standards.

With the increase of residential electricity load, the requirements for the insulation degree of the distribution station area are getting higher and higher, and the level of safe electricity consumption in rural areas has been continuously improved. In the prior art, low-voltage power distribution cabinets use switching elements such as air switches, AC contactors, and leakage protectors. The wiring of the secondary line is complicated, and it will affect the circuit due to poor contact, and maintenance is more troublesome. And security measures are poor.

Low-voltage line insulated wires are more and more widely used in distribution stations. If the insulated wires are not installed with grounding rings for electrical inspection or the insulation layer of the wires is damaged, the grounding wires will not be installed, which will cause great difficulties for low-voltage line maintenance. At present, when a low-voltage insulated line without an electric test grounding ring needs to be repaired, the grounding operation is generally to pull the AC contactor in the low-voltage power distribution cabinet, remove the three-phase fusion tube, and then install it at the pile head under the fuse. Ground wire.

Contents of the invention

The utility model provides a building block type power distribution cabinet with a grounding knife, and its purpose is to simplify the electrical circuit of the power distribution cabinet and improve its operation safety.

In order to achieve the above object, the utility model has taken the following technical solutions:

The building block distribution cabinet with grounding knife provided by the utility model adopts the structure of double building block protection switch and secondary protection, including primary general protection, secondary branch protection circuit, and a double-head isolating switch connected underneath. , the upper end is connected to the low-voltage busbar of the transmission line, and the lower end is grounded.

The power distribution cabinet adopts a building block switch integrating all functions of zero sequence transformer, leakage relay, AC contactor and air circuit breaker, and the air circuit breaker is the main switch.

The substation grounding switch is used in the power distribution cabinet.

In the power distribution cabinet described above, the incoming line current transformer is connected in series with the ammeter, the voltmeter is connected to the changeover switch and the fuse is connected in series to the incoming three-phase power supply; It is three-way or four-way, connected to the second-level building block type protection switch; the outlet terminal is connected to the lightning arrester, and connected to the indicator light and double-head isolating switch.

The beneficial effect of adopting the above technical scheme is: in terms of safety protection, double comprehensive protection is adopted, the secondary wiring is reduced, and the product performance is more perfect; the combination of zero sequence transformer, leakage relay, AC contactor and air circuit breaker is adopted. The building block switch with all functions in one, with air circuit breaker as the main switch, has large breaking capacity and accurate breaking time; reliable action performance, less misoperation, stable operation, and no power consumption; it has time-delay action characteristics and cannot skip tripping; It has complete protection functions such as residual current protection, overload protection, short circuit protection, phase loss and undervoltage protection, zero break protection, and reclosing; the digital display form has real-time display, trip display, and button display functions, and can display the residual current of the line in real time Value and maximum phase, the current operating current value gear, when tripping, it will display the reason for tripping, the phase that caused the tripping and the residual current value at the time of tripping; it can display the total number of tripping and blocking times; the wiring is four in and four out, The residual current action value is multi-level fixed and adjustable, easy to use, and reduces the secondary wiring; the introduction of the substation grounding switch makes the low-voltage power distribution cabinet have the function of the grounding switch, that is, an additional connection is added at the outlet of the low-voltage power distribution cabinet. location, and by installing the switch knife in series between the low-voltage outgoing line and the ground, the operation of the switch knife is used to realize the line inspection status, eliminate the safety hazard of installing the ground wire in the low-voltage power distribution cabinet, and improve the protection of personnel on the one hand On the other hand, it makes the grounding operation on the job site simple, fast and reliable.

Description of drawings

The following is a brief description of the accompanying drawings in this manual:

Fig. 1 is a circuit diagram of the utility model.

Labeled in the figure:

1. Incoming line current transformer, 2. Ammeter, 3. Voltmeter, 4. Transfer switch, 5. Fuse, 6. Knife switch, 7. Primary building block protection switch, 8. Secondary building block protection switch, 9. Lightning arrester, 10. Indicator light, 11. Double-head isolating switch.

Detailed ways

Below in conjunction with accompanying drawing, relevant specific contents such as structure, effect, working principle of the present utility model are described in detail:

As shown in Figure 1, in the power distribution cabinet described in the utility model, the incoming current transformer 1 is connected in series with the ammeter 2, and the voltmeter 3 is connected to the changeover switch 4 and the fuse 5 is connected in series to the incoming three-phase power supply; three-phase four The line power supply is connected to the first-level building block protection switch 7 through the knife switch 6, which is divided into three or four lines, and connected to the second-level building block protection switch 8;

The building block distribution cabinet with grounding knife provided by the utility model adopts the structure of double building block protection switch and secondary protection, including primary general protection, secondary branch protection circuit, and a double-head isolating switch connected underneath. , the upper end is connected to the low-voltage busbar of the transmission line, and the lower end is grounded. Double comprehensive protection is adopted, the secondary wiring is reduced, and the product performance is more perfect.

The power distribution cabinet described in the utility model adopts a building block switch integrating all functions of zero-sequence transformer, leakage relay, AC contactor and air circuit breaker, and the air circuit breaker is the main switch. Large breaking capacity, accurate breaking time; reliable action performance, less misoperation, stable operation, no power consumption; with delay action characteristics, can not skip tripping; with residual current protection, overload protection, short circuit protection, phase loss and undervoltage protection, Complete protection functions such as zero-break protection and reclosing

In the power distribution cabinet described in the utility model, a substation grounding switch is adopted. Make the low-voltage power distribution cabinet have the function of the grounding switch, that is, add a grounding point at the outlet of the low-voltage power distribution cabinet, and install the switch in series between the low-voltage outlet and the ground, and use the operation of the switch to realize line maintenance. State, eliminate the potential safety hazard of installing grounding wires in low-voltage power distribution cabinets, on the one hand, improve the protection of personnel and equipment safety, and on the other hand, make the grounding operation on the job site simple, fast and reliable.

The utility model has been exemplarily described above in conjunction with the accompanying drawings. Obviously, the specific implementation of the utility model is not limited by the above-mentioned methods, as long as various insubstantial improvements are made by adopting the method concept and technical solutions of the utility model, or Directly applying the ideas and technical solutions of the utility model to other occasions without improvement is within the protection scope of the utility model.

Claims (4)

1, a kind of cordwood system type power distribution cabinet with the ground connection plug-in strip; it is characterized in that: described power distribution cabinet adopts the structure of dual cordwood system type protection switch, second class protection, comprises that one-level is always protected, secondary branch protection loop, connects the double end isolating switch down; upper end connection electric transmission line low-voltage bus bar, lower end ground connection.

2, the cordwood system type power distribution cabinet of band ground connection plug-in strip according to claim 1, it is characterized in that: adopting the cordwood system type switch of the repertoire that integrates zero-sequence transformer, leakage relay, A.C. contactor, air circuit in the described power distribution cabinet, is main switch with the air circuit.

3, the cordwood system type power distribution cabinet of band ground connection plug-in strip according to claim 1 and 2 is characterized in that: adopt the substation grounding plug-in strip in the described power distribution cabinet.

4, the cordwood system type power distribution cabinet of band ground connection plug-in strip according to claim 1 and 2, it is characterized in that: in the described power distribution cabinet, inlet wire current instrument transformer (1) is connected with ammeter (2), and voltmeter (3) connects conversion switch (4) serial connection fuse (5) and taps into the line three phase mains; Three-phase four-wire power connects one-level cordwood system type protection switch (7) through disconnecting link (6), is divided into three the road or four the tunnel, connects secondary cordwood system type protection switch (8); Outlet termination lightning arrester (9), and connect indicator light (10), double end isolating switch (11).