CN203895955U - Neutral-line-shortage and neutral-line-breakage automatic protecting device - Google Patents

Abstract

The utility model discloses an automatic zero-off and zero-off protection device, which belongs to the technical field of electric power protection devices. Including the control part circuit and the detection part circuit, the control part circuit includes the auxiliary contact of the shunt circuit breaker and the relay; the detection part circuit includes the relay KC, the stop button SB1 of the shunt circuit breaker QF and the leakage protector RCD; it also includes The alarm part circuit is composed of the power supply E, the dynamic auxiliary contact QF3 of the shunt circuit breaker QF, the alarm R and the switch K, which are electrically connected in sequence. The utility model is simple in structure, easy to use, strong in safety, high in intelligence, strong in versatility, low in cost, basically requires no maintenance, and is convenient to change or connect circuits on site; it is especially suitable for three-phase four-wire transformers and three-phase four-wire transformers. used on electrical equipment.

Description

Zero missing and zero breaking automatic protection device

technical field

The utility model belongs to the technical field of electric power protection devices.

Background technique

At present, due to various situations and reasons, the zero line of the lighting transformer is blown out, such as the zero line in the metering box in the JP cabinet is blown out, the zero line on the low voltage side of the transformer is blown out, etc., which will bring extremely serious consequences. . Because the unbalanced load will lead to the unbalanced three-phase voltage, if the zero line is disconnected, the unbalanced three-phase load voltage will be more serious, which will change the working characteristics of electrical equipment, and the equipment will not work if the voltage is too low. Excessive voltage shortens the life of equipment, causing many users to burn out electrical equipment, and even cause fires, causing serious economic losses to users, unnecessary compensation liabilities and economic losses to power supply companies, and seriously affecting the power supply companies. Brand. Moreover, once the neutral line is disconnected, the electrical equipment that uses protection to connect to zero will lose its protective effect. Once the equipment leaks electricity, it will cause personal electric shock. cause personal electric shock accidents.

According to the actual situation that the zero line is disconnected in the three-phase four-wire low-voltage power distribution system, and the neutral point potential shift causes many accidents due to overvoltage, we need to research and develop a kind of easy-to-manufacture detection and protection of missing and broken neutral lines. device to ensure the safety of electricity in the low-voltage power distribution system.

Utility model content

The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide an automatic protection device for missing and breaking zeros, which has simple structure, convenient use, strong safety, high degree of intelligence, strong versatility and low cost , basically no maintenance, easy to change or connect circuits on site; especially suitable for use on three-phase four-wire transformers (such as lighting transformers) and three-phase four-wire electrical equipment.

In order to solve the problems of the technologies described above, the technical solution adopted by the utility model is:

An automatic zero-break and zero-break protection device, including a control part circuit and a detection part circuit, wherein:

The control part circuit includes a shunt circuit breaker QF and auxiliary contacts KC1 and KC2 of the relay KC, the shunt circuit breaker QF is provided with a shunt coil F1 and more than one auxiliary contact; the shunt circuit breaker The moving-closing auxiliary contact ⅠQF1 of QF is connected to the A-phase line of the three-phase power supply, and the other end is connected to the moving-breaking auxiliary contact ⅠKC1 of the relay KC and the shunt coil F1 in turn, and then through the moving-breaking auxiliary contact of the relay KC ⅡKC2 and the moving-closing auxiliary contact of the shunt circuit breaker QF ⅡQF2 are connected to the B-phase line of the three-phase power line;

The detection part circuit includes a relay KC, the two ends of the coil of the relay KC are respectively connected with the neutral line N and the C-phase line of the three-phase power supply.

The detection part circuit also includes a stop button SB1 of the shunt circuit breaker QF, one end of the stop button SB1 is connected to the C-phase line of the three-phase power supply, and the other end is connected to the neutral line N through the coil of the relay KC.

The detection part circuit also includes a leakage protector RCD, one end of the stop button SB1 is connected to the C-phase line of the three-phase power supply, the other end is connected to the zero line through the leakage protector RCD, and the two ends of the coil of the relay KC are respectively connected to the leakage current The protector RCD is connected to the neutral line N.

It also includes an alarm part circuit. The alarm part circuit includes a power supply E, a dynamic-break auxiliary contact QF3 of a shunt circuit breaker QF, an alarm R and a switch K that are electrically connected in sequence.

The power supply E is a lithium battery.

The alarm R is a buzzer alarm.

The shunt circuit breaker QF is RKM1-400S/3340 model, CM1-400S/3340 model or RMM1-100H/3340 model air switch produced by Shanghai People's Electric Switch Factory Group.

The beneficial effects produced by adopting the above-mentioned technical scheme are: the utility model has the advantages of simple structure, convenient use, strong safety, high degree of intelligence, strong versatility, low cost, basically no maintenance, convenient on-site modification or connection of circuits, especially suitable for Used on three-phase four-wire transformers (such as lighting transformers) and three-phase four-wire electrical equipment; including the control part circuit and the detection part circuit, the circuit is simple and reliable; the detection part circuit also includes a stop button to effectively verify the main contact of the shunt circuit breaker The reliable on-off of the point, and the leakage protector prevent personal electric shock accidents caused by equipment leakage; it also includes the alarm part circuit, which is safe and intelligent, and realizes timely alarm, which is convenient for the operation and maintenance personnel to find out the lack of zero, zero accident; the power supply E is a lithium battery with long service life, large capacity, high temperature resistance, small size, light weight, safety and environmental protection; the alarm is a buzzer alarm with obvious alarm effect and simple operation; the shunt circuit breaker QF is RKM1-400S/3340 model, CM1-400S/3340 model or RMM1-100H/3340 model air switch produced by Shanghai People's Electric Switch Factory Group. The components are easy to get, the cost is low, and the performance is stable.

Description of drawings

Below in conjunction with accompanying drawing and specific embodiment, the utility model is described in further detail.

Fig. 1 is the schematic circuit diagram of the utility model embodiment.

FIG. 2 is a schematic structural diagram of the shunt circuit breaker QF in FIG. 1 .

QF, shunt circuit breaker, KC, relay, QF1, shunt circuit breaker QF moving auxiliary contact Ⅰ, KC1, relay KC moving auxiliary contact Ⅰ, F1, shunt coil, KC2, relay KC moving auxiliary contact Head Ⅱ, QF2, shunt circuit breaker QF moving auxiliary contact Ⅱ, SB1, stop button, RCD, leakage protector, E, power supply, QF3, shunt circuit breaker QF moving auxiliary contact, R, alarm, K. Switch, 1. Main contact, 2. Free release mechanism, 3. Overcurrent release, 4. Shunt coil release, 5. Thermal release, 6. Undervoltage release.

Detailed ways

Referring to Fig. 1 and Fig. 2, an automatic zero-break and zero-break protection device includes a control part circuit and a detection part circuit, the circuit is simple, and the degree of intelligence is high, wherein:

The control part circuit includes the shunt circuit breaker QF and the auxiliary contacts KC1 and KC2 of the relay KC. The shunt circuit breaker QF is selected from the RKM1-400S/3340 type air switch produced by Shanghai People's Electric Switch Factory Group (also available For other types of circuit breakers with shunt coils and auxiliary contacts), the components are easy to obtain, low in cost, and stable in performance. It is equipped with a shunt coil F1 and three auxiliary contacts QF1, QF2 and QF3; The moving-closing auxiliary contact ⅠQF1 of the relay QF is connected with the A-phase line of the three-phase power supply, and the other end is connected with the moving-breaking auxiliary contact ⅠKC1 of the relay KC and the shunt coil F1 in turn, and then through the moving-breaking auxiliary contact of the relay KC The head IIKC2 and the moving-close auxiliary contact IIQF2 of the shunt circuit breaker QF are connected to the B-phase line of the three-phase power line.

The detection part circuit includes a relay KC. In order to enhance the personal safety of the line and verify the reliable on-off of the main contact 1 of the shunt circuit breaker QF, a leakage protector RCD and a stop button SB1 of the shunt circuit breaker QF are also provided. , the connection relationship between the relay KC, the leakage protector RCD and the stop button SB1 is: one end of the stop button SB1 is connected to the C-phase line of the three-phase power supply, the other end is connected to the zero line through the leakage protector RCD, and the relay KC The two ends of the coil are respectively connected to the leakage protector RCD and the neutral line N; the stop button SB1 is located on the panel of the shunt circuit breaker QF, and is used to detect whether the shunt circuit breaker QF can normally disconnect the main contact 1, and it serves as a test The leakage protector RCD is connected with multiple shunt air switches. When a leakage accident occurs in the equipment related to the shunt air switch, the leakage protector RCD will act to prevent personal electric shock and improve electricity safety.

In order to let the operation and maintenance personnel know the occurrence of zero-off and zero-off faults of electrical equipment at the first time, an alarm part circuit is also provided. Auxiliary contact QF3, alarm R and switch K, power supply E is a lithium battery, long service life, large capacity, high temperature resistance, small size, light weight, safety and environmental protection; alarm R is a buzzer alarm, the alarm effect is obvious, The operation is simple, and it is convenient for operation and maintenance personnel to quickly repair.

The auxiliary contacts QF1, QF2 and QF3 of the shunt circuit breaker QF are drawn outside the plastic case, and the connector of the shunt coil release 4 can be drawn out from the inside or wired inside, which is convenient for wiring.

When the upper end of the shunt circuit breaker QF has power, the leakage protector RCD works normally. The voltage 220V power supply is sent to the coil of the relay KC, and the normally closed contacts KC1 and KC2 of the relay KC are disconnected. When the shunt circuit breaker QF is closed, its normally open contacts QF1 and QF2 are closed, but at this time the normally closed contacts KC1 and KC2 of the relay KC are disconnected, and the shunt coil F1 of the shunt circuit breaker QF is still disconnected. electricity. When the zero line is disconnected, the relay KC coil closes the normally open contact of the relay KC due to the loss of voltage, and the shunt coil F1 of the shunt circuit breaker QF is energized, and the armature of the shunt circuit breaker QF drives the free tripping mechanism 2 action, so that the main contact 1 is disconnected to protect the following equipment from being burned, and QF1 and QF2 are also disconnected at the same time, protecting the shunt coil F1 from being burned; when the main contact 1 of the shunt circuit breaker QF is disconnected, The dynamic breaker auxiliary contact QF3 of the shunt circuit breaker QF is closed, the alarm R is turned on and the whistle is sounded to remind the staff that there is a zero-off or zero-off fault in the line, and the alarm R stops alarming after the staff pulls the switch K.

When the shunt coil release 4 is working normally, its shunt coil F1 is powered off, and when the shunt coil F1 is energized, the armature drives the free tripping mechanism 2 to act, so that the main contact 1 is disconnected. The shunt coil release 4 is a release that is excited by a voltage source, and it works for a short time. Generally, the power-on time of the shunt coil F1 cannot exceed 1S, otherwise it will be burned. In order to prevent the shunt coil F1 from being burned, when the main contact of the shunt circuit breaker QF is disconnected, its moving auxiliary contacts QF1 and QF2 are also disconnected at the same time, so that the shunt coil F1 will not be burned when the power is off, effectively protecting device.

This is the connection of one of the switches, and the other shunt switches are connected according to this connection relationship, which will not be described one by one.

The device is applied to lighting transformers with good effect, and can also be widely used in various three-phase four-wire electrical equipment and other transformer fields, and has high popularization and application value. the

Claims (7)

1. Lack zero, an automatic safety device off zero, it is characterized in that, comprise control section circuit and test section circuit, wherein:

   Described control section circuit comprises auxiliary contact KC1, the KC2 of shunt circuit breaker QF and relay K C, and described shunt circuit breaker QF is provided with shunt opening coil F1 and 1 above auxiliary contact; The dynamic circuit connector auxiliary contact I QF1 of described shunt circuit breaker QF is connected with the A phase line of three phase mains, the other end successively warp is connected with dynamic circuit breaker auxiliary contact I KC1 and the shunt opening coil F1 of relay K C, and then is connected with three-phase power line B phase line through the dynamic circuit breaker auxiliary contact II KC2 of relay K C and the dynamic circuit connector auxiliary contact II QF2 of shunt circuit breaker QF;

   Described test section circuit comprises relay K C, and the coil two ends of described relay K C are connected with the C phase line of zero line N and three phase mains respectively.
2. According to claim 1 lack zero, automatic safety device off zero; it is characterized in that; described test section circuit also comprises the stop button SB1 of shunt circuit breaker QF; described stop button SB1 one end is connected with the C phase line of three phase mains, and the other end joins by coil and the zero line N of relay K C.
3. According to claim 2 lack zero, automatic safety device off zero; it is characterized in that; described test section circuit also comprises earth leakage protective device RCD; described stop button SB1 one end is connected with the C phase line of three phase mains; the other end joins through earth leakage protective device RCD and zero line, and the coil two ends of relay K C join with earth leakage protective device RCD and zero line N respectively.
4. According to described in claim 1,2 or 3 lack zero, automatic safety device off zero; characterized by further comprising warning partial circuit, described warning partial circuit comprises dynamic circuit breaker auxiliary contact QF3, alarm R and the K switch of power supply E, the shunt circuit breaker QF of electrical connection successively.
5. According to claim 4 lack zero, automatic safety device off zero, it is characterized in that, described power supply E is lithium battery.
6. According to claim 4 lack zero, automatic safety device off zero, it is characterized in that, described alarm R is buzzer siren.
7. According to claim 1 lack zero, automatic safety device off zero; it is characterized in that, described shunt circuit breaker QF is RKM1-400S/3340 model, CM1-400S/3340 model or the RMM1-100H/3340 model air switch that originates from group of Shanghai People's appliance switch factory.