CN202854219U - Undervoltage, voltage loss, and phase loss detection circuit - Google Patents

Abstract

The utility model provides an undervoltage, voltage loss, and phase loss detection circuit, which includes a phase line and a neutral line connected to the phase line, and the phase line and the neutral line are connected through a voltage detection module; the voltage detection module includes a first relay and a second relay, The first relay includes the first control system and the first normally open contact, the second relay includes the second control system and the second normally open contact; the phase line is connected to the neutral line through the first control system, and the neutral line is connected to the neutral line through the second control system The system is connected to the first normally open contact, the first normally open contact is connected to the phase line through the contact switch, the first normally open contact is also connected to the phase line through the second normally open contact, and the second normally open contact It is also connected to the zero line through the indicator light. The undervoltage, voltage loss, and phase loss detection circuit can accurately judge the phenomenon of undervoltage, voltage loss, and phase loss of the external line, which brings great help to the power distribution operation, effectively shortens the delay time of power failure, and improves the production and operation of the factory. Bring huge intangible benefits.

Description

Undervoltage and loss of voltage and phase loss detection circuit

technical field

The utility model relates to a detection circuit for undervoltage, voltage loss, and phase loss.

Background technique

A three-phase AC circuit is a circuit powered by a three-phase AC power supply, referred to as a three-phase circuit. A three-phase AC power supply refers to a power supply that can provide three voltages or currents with the same frequency but different phases, and the most commonly used is a three-phase AC generator. The phase difference of each phase voltage of the three-phase alternator is 120°, and the order in which the voltage of each phase leads or lags between them is called the phase sequence. The three-phase AC motor rotates forward when it is powered by positive sequence voltage, and reverses when it is powered by negative sequence voltage. Therefore, you must pay attention to the phase sequence when using a three-phase AC power supply. Some production equipment that needs to be reversed can control the forward and reverse of the three-phase AC motor by changing the phase sequence of the power supply. A three-phase circuit is a special AC circuit consisting of a three-phase power supply, a three-phase load and a three-phase transmission line. The three-phase power supply used in the power system is mostly a symmetrical three-phase power supply, which is a three-phase power supply composed of three sinusoidal voltage sources with the same frequency, the same amplitude, and a phase difference of 120°.

A relay is an electrical control device. It has an interactive relationship between the control system (also known as the input circuit) and the controlled system (also known as the output circuit), and is usually used in automatic control circuits. It is actually a kind of control of large current operation with small current "automatic switch". Therefore, the relay plays the role of automatic adjustment, safety protection, and conversion circuit in the circuit.

In the factory, the power distribution room of the factory is responsible for the power supply of the whole factory and the task of changing from external lines to internal lines. It is the center of the power supply of the whole plant. However, tripping often occurs due to various factors, which has a certain impact on production. . When a tripping situation occurs, as a maintenance personnel, it is first necessary to judge whether it is an external line fault or an internal line fault. If it is an internal line failure, emergency repair measures should be taken in time. If it is an external line factor, coordination is required to restore power supply. However, in the current circuit system, when a power failure occurs, it is impossible to immediately determine whether the external line is faulty or the internal line is faulty. In order to judge the external line, this will bring a lot of trouble to the maintenance and prolong the time for power supply recovery.

Utility model content

In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide a detection circuit for undervoltage, voltage loss, and phase loss, which is used to solve the failure of judging undervoltage, voltage loss, and phase failure when the external line is faulty in the prior art. The problem.

In order to achieve the above purpose and other related purposes, the utility model provides an undervoltage and loss of voltage and phase loss detection circuit, including a phase line and a neutral line connected to the phase line, and the phase line and the neutral line are connected through a voltage detection module; the voltage detection module Including the first relay and the second relay, the first relay includes the first control system and the first normally open contact, the second relay includes the second control system and the second normally open contact; the phase line passes through the first control system and the zero The zero line is connected to the first normally open contact through the second control system, the first normally open contact is connected to the phase line through the contact switch, and the first normally open contact is also connected to the phase line through the second normally open contact The second normally open contact is also connected to the zero line through the indicator light.

Preferably, the number of phase wires is three.

As mentioned above, the detection circuit for undervoltage, voltage loss, and phase loss of the utility model has the following beneficial effects:

By installing the undervoltage and phase loss detection circuit on the outside line, when the voltage loses voltage, the first relay stops working, which causes the second relay to stop working, and the indicator light goes out; when the voltage is undervoltage to the voltage of the first relay When the value is set, the first relay will stop working, which will cause the second relay to stop working, and the indicator light will go out; observe which indicator light is off, you can determine which phase has a problem, so that you can quickly judge undervoltage, loss of voltage, and lack of voltage. phase situation.

The undervoltage, voltage loss, and phase loss detection circuit can accurately judge the undervoltage, voltage loss, and phase loss of the external line, which brings great help to the power distribution operation, effectively shortens the delay time of power failure, and improves the production and operation of the factory. Bring huge intangible benefits.

Description of drawings

Fig. 1 is a schematic circuit diagram of a specific embodiment of the detection circuit for voltage loss, voltage loss, and phase loss of the present invention.

Component designation description

Detailed ways

The implementation of the present utility model is illustrated by specific specific examples below, and those skilled in the art can easily understand other advantages and effects of the present utility model from the content disclosed in this specification.

See Figure 1. It should be noted that the structures, proportions, sizes, etc. shown in the drawings attached to this specification are only used to match the content disclosed in the specification, for those who are familiar with this technology to understand and read, and are not used to limit the implementation of the utility model Therefore, it has no technical substantive meaning. Any modification of structure, change of proportional relationship or adjustment of size shall still fall within the scope of The technical content disclosed by the utility model must be within the scope covered. At the same time, terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description and are not used to limit this specification. The practicable range of the utility model, and the change or adjustment of its relative relationship, without any substantial change in the technical content, shall also be regarded as the practicable scope of the utility model.

As shown in Figure 1, the utility model provides a detection circuit for undervoltage, voltage loss, and phase loss. The line and the neutral line are connected through a voltage detection module; the voltage detection module includes a first relay and a second relay, the first relay includes a first control system 11 and a first normally open contact 12, and the second relay includes a second control system 21 and The second normally open contact 22; the phase line is connected to the neutral line through the first control system 11, the neutral line is connected to the first normally open contact 12 through the second control system 21, and the first normally open contact 12 is passed through a contact switch 3 is connected to the phase line, the first normally open contact 12 is also connected to the phase line through the second normally open contact 22, and the second normally open contact 22 is also connected to the neutral line through the indicator light 4; the circuit to be detected is three Phase four-wire circuit, the phase line has three phases A, B, and C, and there is a voltage detection module between each phase line and the neutral line.

When the circuit starts, the first control system 11 is energized, the first normally open contact 12 is closed, the contact switch 3 is pressed, the second control system 21 is powered, the second normally open contact 22 is closed, and the indicator light 4 is on , adjust the voltage setting value of the first control system 11, so that the voltage setting value is the minimum voltage value for the normal operation of the circuit, so that the indicator light 4 is always on when the circuit is working normally.

When the voltage of the first control system 11 is lower than the voltage setting value, the first normally open contact 12 is disconnected, the second control system 21 is powered off, the second normally open contact 22 is disconnected, and the indicator light 4 is turned off. According to the state of the indicator light 4, it can be judged which phase circuit has undervoltage, voltage loss or phase loss.

To sum up, the undervoltage, voltage loss, and phase loss detection circuit of the utility model can accurately judge the undervoltage, voltage loss, and phase loss of the external line, which brings great help to the power distribution operation and effectively shortens the delay of power failure. Time, bringing huge intangible benefits to the production and operation of the factory. Therefore, the utility model effectively overcomes various shortcomings in the prior art and has high industrial application value.

The above-mentioned embodiments only illustrate the principles and effects of the present utility model, but are not intended to limit the present utility model. Anyone familiar with this technology can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed in the utility model should still be covered by the claims of the utility model.

Claims (2)

1. A detection circuit for undervoltage, voltage loss, and phase loss, comprising a phase wire and a neutral wire connected to the phase wire, characterized in that: the phase wire and the neutral wire are connected through a voltage detection module; the voltage detection The module includes a first relay and a second relay, the first relay includes a first control system (11) and a first normally open contact (12), and the second relay includes a second control system (21) and a second A normally open contact (22); the phase line is connected to the neutral line through the first control system (11), and the neutral line is connected to the first normally open contact through the second control system (21) contacts (12), the first normally open contact (12) is connected to the phase line through the contact switch (3), and the first normally open contact (12) is also connected to the phase line through the second normally open contact The open contact (22) is connected to the phase line, and the second normally open contact (22) is also connected to the neutral line through the indicator light (4). 2. The detection circuit for undervoltage, voltage loss, and phase loss according to claim 1, wherein the number of said phase wires is three.